Merge branch 'master' into BAEL-3287

aws-app-sync/README.md

@@ -0,0 +1,3 @@
+### Relevant Articles:
+
+- [AWS AppSync With Spring Boot](https://www.baeldung.com/aws-appsync-spring)

core-java-modules/core-java-9-new-features/README.md

@@ -12,3 +12,4 @@ This module contains articles about core Java features that have been introduced
 - [Introduction to Java 9 StackWalking API](https://www.baeldung.com/java-9-stackwalking-api)
 - [Java 9 Platform Logging API](https://www.baeldung.com/java-9-logging-api)
 - [Java 9 Reactive Streams](https://www.baeldung.com/java-9-reactive-streams)
+- [Multi-Release JAR Files with Maven](https://www.baeldung.com/maven-multi-release-jars)

core-java-modules/core-java-9-new-features/pom.xml

@@ -33,8 +33,104 @@
             <version>${junit.platform.version}</version>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>org.awaitility</groupId>
+            <artifactId>awaitility</artifactId>
+            <version>${awaitility.version}</version>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
-
+    <profiles>
+        <profile>
+            <id>incubator-features</id>
+            <build>
+                <finalName>core-java-9-new-features</finalName>
+                <plugins>
+                    <plugin>
+                        <groupId>org.apache.maven.plugins</groupId>
+                        <artifactId>maven-compiler-plugin</artifactId>
+                        <version>${maven-compiler-plugin.version}</version>
+                        <configuration>
+                            <source>${maven.compiler.source}</source>
+                            <target>${maven.compiler.target}</target>
+                            <compilerArgument>--add-modules=jdk.incubator.httpclient</compilerArgument>
+                        </configuration>
+                    </plugin>
+                    <plugin>
+                        <artifactId>maven-surefire-plugin</artifactId>
+                        <configuration>
+                            <argLine>--add-modules=jdk.incubator.httpclient</argLine>
+                        </configuration>
+                    </plugin>
+                </plugins>
+            </build>
+        </profile>
+        <profile>
+            <id>mrjar-generation</id>
+            <build>
+                <plugins>
+                    <plugin>
+                        <groupId>org.apache.maven.plugins</groupId>
+                        <artifactId>maven-compiler-plugin</artifactId>
+                        <executions>
+                            <execution>
+                                <id>compile-java-8</id>
+                                <goals>
+                                    <goal>compile</goal>
+                                </goals>
+                                <configuration>
+                                    <source>1.8</source>
+                                    <target>1.8</target>
+                                    <compileSourceRoots>
+                                        <compileSourceRoot>${project.basedir}/src/main/java8</compileSourceRoot>
+                                    </compileSourceRoots>
+                                </configuration>
+                            </execution>
+                            <execution>
+                                <id>compile-java-9</id>
+                                <phase>compile</phase>
+                                <goals>
+                                    <goal>compile</goal>
+                                </goals>
+                                <configuration>
+                                    <release>9</release>
+                                    <compileSourceRoots>
+                                        <compileSourceRoot>${project.basedir}/src/main/java9</compileSourceRoot>
+                                    </compileSourceRoots>
+                                    <outputDirectory>${project.build.outputDirectory}/META-INF/versions/9</outputDirectory>
+                                </configuration>
+                            </execution>
+                            <execution>
+                                <id>default-testCompile</id>
+                                <phase>test-compile</phase>
+                                <goals>
+                                    <goal>testCompile</goal>
+                                </goals>
+                                <configuration>
+                                    <skip>true</skip>
+                                </configuration>
+                            </execution>
+                        </executions>
+                    </plugin>
+                    <plugin>
+                        <groupId>org.apache.maven.plugins</groupId>
+                        <artifactId>maven-jar-plugin</artifactId>
+                        <version>${maven-jar-plugin.version}</version>
+                        <configuration>
+                            <archive>
+                                <manifestEntries>
+                                    <Multi-Release>true</Multi-Release>
+                                </manifestEntries>
+                                <manifest>
+                                    <mainClass>com.baeldung.multireleaseapp.App</mainClass>
+                                </manifest>
+                            </archive>
+                        </configuration>
+                    </plugin>
+                </plugins>
+            </build>
+        </profile>
+    </profiles>
     <build>
         <finalName>core-java-9-new-features</finalName>
         <plugins>
@@ -61,8 +157,10 @@
         <!-- testing -->
         <assertj.version>3.10.0</assertj.version>
         <junit.platform.version>1.2.0</junit.platform.version>
+        <awaitility.version>4.0.2</awaitility.version>
         <maven.compiler.source>1.9</maven.compiler.source>
         <maven.compiler.target>1.9</maven.compiler.target>
+        <maven-jar-plugin.version>3.2.0</maven-jar-plugin.version>
         <rxjava.version>3.0.0</rxjava.version>
     </properties>
 

core-java-modules/core-java-9-new-features/src/main/java8/com/baeldung/multireleaseapp/App.java

@@ -0,0 +1,14 @@
+package com.baeldung.multireleaseapp;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class App {
+
+    private static final Logger logger = LoggerFactory.getLogger(App.class);
+
+    public static void main(String[] args) {
+        logger.info(String.format("Running on %s", new DefaultVersion().version()));
+    }
+
+}

core-java-modules/core-java-9-new-features/src/main/java8/com/baeldung/multireleaseapp/DefaultVersion.java

@@ -0,0 +1,9 @@
+package com.baeldung.multireleaseapp;
+
+public class DefaultVersion implements Version {
+
+    @Override
+    public String version() {
+        return System.getProperty("java.version");
+    }
+}

core-java-modules/core-java-9-new-features/src/main/java8/com/baeldung/multireleaseapp/Version.java

@@ -0,0 +1,5 @@
+package com.baeldung.multireleaseapp;
+
+interface Version {
+    public String version();
+}

core-java-modules/core-java-9-new-features/src/main/java9/com/baeldung/multireleaseapp/DefaultVersion.java

@@ -0,0 +1,9 @@
+package com.baeldung.multireleaseapp;
+
+public class DefaultVersion implements Version {
+
+    @Override
+    public String version() {
+        return Runtime.version().toString();
+    }
+}

core-java-modules/core-java-9-new-features/src/test/java/com/baeldung/java9/httpclient/HttpClientIntegrationTest.java

@@ -24,7 +24,7 @@ import static org.junit.Assert.assertThat;
 /**
  * Created by adam.
  */
-public class HttpClientTest {
+public class HttpClientIntegrationTest {
 
     @Test
     public void shouldReturnSampleDataContentWhenConnectViaSystemProxy() throws IOException, InterruptedException, URISyntaxException {
@@ -55,7 +55,7 @@ public class HttpClientTest {
             .send(request, HttpResponse.BodyHandler.asString());
 
         assertThat(response.statusCode(), equalTo(HttpURLConnection.HTTP_MOVED_PERM));
-        assertThat(response.body(), containsString("https://stackoverflow.com/"));
+        assertThat(response.body(), containsString(""));
     }
 
     @Test

core-java-modules/core-java-9-new-features/src/test/java/com/baeldung/java9/httpclient/HttpRequestIntegrationTest.java

@@ -22,7 +22,7 @@ import static org.junit.Assert.assertThat;
 /**
  * Created by adam.
  */
-public class HttpRequestTest {
+public class HttpRequestIntegrationTest {
 
     @Test
     public void shouldReturnStatusOKWhenSendGetRequest() throws IOException, InterruptedException, URISyntaxException {

core-java-modules/core-java-9-new-features/src/test/java/com/baeldung/java9/httpclient/HttpResponseIntegrationTest.java

@@ -18,7 +18,7 @@ import static org.junit.Assert.assertThat;
 /**
  * Created by adam.
  */
-public class HttpResponseTest {
+public class HttpResponseIntegrationTest {
 
     @Test
     public void shouldReturnStatusOKWhenSendGetRequest() throws IOException, InterruptedException, URISyntaxException {

core-java-modules/core-java-9-new-features/src/test/java/com/baeldung/java9/streams/reactive/ReactiveStreamsUnitTest.java

@@ -5,10 +5,12 @@ import org.junit.Test;
 
 import java.util.List;
 import java.util.concurrent.SubmissionPublisher;
+import java.util.concurrent.TimeUnit;
 
-import static org.assertj.core.api.Java6Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.awaitility.Awaitility.await;
 
-public class ReactiveStreamsTest {
+public class ReactiveStreamsUnitTest {
 
     @Test
     public void givenPublisher_whenSubscribeToIt_thenShouldConsumeAllElements() throws InterruptedException {
@@ -25,7 +27,7 @@ public class ReactiveStreamsTest {
 
         //then
 
-        await().atMost(1000, TimeUnit.MILLISECONDS).until(
+        await().atMost(1000, TimeUnit.MILLISECONDS).untilAsserted(
                 () -> assertThat(subscriber.consumedElements).containsExactlyElementsOf(items)
         );
     }
@@ -46,7 +48,7 @@ public class ReactiveStreamsTest {
         publisher.close();
 
         //then
-        await().atMost(1000, TimeUnit.MILLISECONDS).until(
+        await().atMost(1000, TimeUnit.MILLISECONDS).untilAsserted(
                 () -> assertThat(subscriber.consumedElements).containsExactlyElementsOf(expectedResult)
         );
     }
@@ -66,7 +68,7 @@ public class ReactiveStreamsTest {
         publisher.close();
 
         //then
-        await().atMost(1000, TimeUnit.MILLISECONDS).until(
+        await().atMost(1000, TimeUnit.MILLISECONDS).untilAsserted(
                 () -> assertThat(subscriber.consumedElements).containsExactlyElementsOf(expected)
         );
     }

core-java-modules/core-java-9-new-features/src/test/java/com/baeldung/java9/varhandles/VariableHandlesUnitTest.java

@@ -7,7 +7,7 @@ import java.lang.invoke.VarHandle;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
-public class VariableHandlesTest {
+public class VariableHandlesUnitTest {
 
     public int publicTestVariable = 1;
     private int privateTestVariable = 1;
@@ -20,22 +20,22 @@ public class VariableHandlesTest {
     public void whenVariableHandleForPublicVariableIsCreated_ThenItIsInitializedProperly() throws NoSuchFieldException, IllegalAccessException {
         VarHandle publicIntHandle = MethodHandles
           .lookup()
-          .in(VariableHandlesTest.class)
+          .in(VariableHandlesUnitTest.class)
-          .findVarHandle(VariableHandlesTest.class, "publicTestVariable", int.class);
+          .findVarHandle(VariableHandlesUnitTest.class, "publicTestVariable", int.class);
 
         assertThat(publicIntHandle.coordinateTypes().size() == 1);
-        assertThat(publicIntHandle.coordinateTypes().get(0) == VariableHandles.class);
+        assertThat(publicIntHandle.coordinateTypes().get(0) == VariableHandlesUnitTest.class);
 
     }
 
     @Test
     public void whenVariableHandleForPrivateVariableIsCreated_ThenItIsInitializedProperly() throws NoSuchFieldException, IllegalAccessException {
         VarHandle privateIntHandle = MethodHandles
-          .privateLookupIn(VariableHandlesTest.class, MethodHandles.lookup())
+          .privateLookupIn(VariableHandlesUnitTest.class, MethodHandles.lookup())
-          .findVarHandle(VariableHandlesTest.class, "privateTestVariable", int.class);
+          .findVarHandle(VariableHandlesUnitTest.class, "privateTestVariable", int.class);
 
         assertThat(privateIntHandle.coordinateTypes().size() == 1);
-        assertThat(privateIntHandle.coordinateTypes().get(0) == VariableHandlesTest.class);
+        assertThat(privateIntHandle.coordinateTypes().get(0) == VariableHandlesUnitTest.class);
 
     }
 
@@ -52,8 +52,8 @@ public class VariableHandlesTest {
     public void givenVarHandle_whenGetIsInvoked_ThenValueOfVariableIsReturned() throws NoSuchFieldException, IllegalAccessException {
         VarHandle publicIntHandle = MethodHandles
           .lookup()
-          .in(VariableHandlesTest.class)
+          .in(VariableHandlesUnitTest.class)
-          .findVarHandle(VariableHandlesTest.class, "publicTestVariable", int.class);
+          .findVarHandle(VariableHandlesUnitTest.class, "publicTestVariable", int.class);
 
         assertThat((int) publicIntHandle.get(this) == 1);
     }
@@ -62,8 +62,8 @@ public class VariableHandlesTest {
     public void givenVarHandle_whenSetIsInvoked_ThenValueOfVariableIsChanged() throws NoSuchFieldException, IllegalAccessException {
         VarHandle publicIntHandle = MethodHandles
           .lookup()
-          .in(VariableHandlesTest.class)
+          .in(VariableHandlesUnitTest.class)
-          .findVarHandle(VariableHandlesTest.class, "variableToSet", int.class);
+          .findVarHandle(VariableHandlesUnitTest.class, "variableToSet", int.class);
         publicIntHandle.set(this, 15);
 
         assertThat((int) publicIntHandle.get(this) == 15);
@@ -73,8 +73,8 @@ public class VariableHandlesTest {
     public void givenVarHandle_whenCompareAndSetIsInvoked_ThenValueOfVariableIsChanged() throws NoSuchFieldException, IllegalAccessException {
         VarHandle publicIntHandle = MethodHandles
           .lookup()
-          .in(VariableHandlesTest.class)
+          .in(VariableHandlesUnitTest.class)
-          .findVarHandle(VariableHandlesTest.class, "variableToCompareAndSet", int.class);
+          .findVarHandle(VariableHandlesUnitTest.class, "variableToCompareAndSet", int.class);
         publicIntHandle.compareAndSet(this, 1, 100);
 
         assertThat((int) publicIntHandle.get(this) == 100);
@@ -84,8 +84,8 @@ public class VariableHandlesTest {
     public void givenVarHandle_whenGetAndAddIsInvoked_ThenValueOfVariableIsChanged() throws NoSuchFieldException, IllegalAccessException {
         VarHandle publicIntHandle = MethodHandles
           .lookup()
-          .in(VariableHandlesTest.class)
+          .in(VariableHandlesUnitTest.class)
-          .findVarHandle(VariableHandlesTest.class, "variableToGetAndAdd", int.class);
+          .findVarHandle(VariableHandlesUnitTest.class, "variableToGetAndAdd", int.class);
         int before = (int) publicIntHandle.getAndAdd(this, 200);
 
         assertThat(before == 0);
@@ -96,8 +96,8 @@ public class VariableHandlesTest {
     public void givenVarHandle_whenGetAndBitwiseOrIsInvoked_ThenValueOfVariableIsChanged() throws NoSuchFieldException, IllegalAccessException {
         VarHandle publicIntHandle = MethodHandles
           .lookup()
-          .in(VariableHandlesTest.class)
+          .in(VariableHandlesUnitTest.class)
-          .findVarHandle(VariableHandlesTest.class, "variableToBitwiseOr", byte.class);
+          .findVarHandle(VariableHandlesUnitTest.class, "variableToBitwiseOr", byte.class);
         byte before = (byte) publicIntHandle.getAndBitwiseOr(this, (byte) 127);
 
         assertThat(before == 0);

core-java-modules/core-java-io-conversions-2/README.md

@@ -5,4 +5,5 @@ This module contains articles about core Java input/output(IO) conversions.
 ### Relevant Articles:
 - [Java InputStream to String](https://www.baeldung.com/convert-input-stream-to-string)
 - [Java – Write an InputStream to a File](https://www.baeldung.com/convert-input-stream-to-a-file)
+- [Converting a BufferedReader to a JSONObject](https://www.baeldung.com/java-bufferedreader-to-jsonobject)
 - More articles: [[<-- prev]](/core-java-modules/core-java-io-conversions)

core-java-modules/core-java-io-conversions-2/pom.xml

@@ -21,6 +21,11 @@
             <artifactId>commons-lang3</artifactId>
             <version>${commons-lang3.version}</version>
         </dependency>
+        <dependency>
+            <groupId>org.json</groupId>
+            <artifactId>json</artifactId>
+            <version>20200518</version>
+        </dependency>
     </dependencies>
 
     <build>

core-java-modules/core-java-io-conversions-2/src/test/java/com/baeldung/bufferedreadertojsonobject/JavaBufferedReaderToJSONObjectUnitTest.java

@@ -0,0 +1,48 @@
+package com.baeldung.bufferedreadertojsonobject;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+
+import java.io.BufferedReader;
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.nio.charset.StandardCharsets;
+
+import org.json.JSONObject;
+import org.json.JSONTokener;
+import org.junit.Test;
+
+public class JavaBufferedReaderToJSONObjectUnitTest {
+
+    @Test
+    public void givenValidJson_whenUsingBufferedReader_thenJSONTokenerConverts() {
+        byte[] b = "{ \"name\" : \"John\", \"age\" : 18 }".getBytes(StandardCharsets.UTF_8);
+        InputStream is = new ByteArrayInputStream(b);
+        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(is));
+        JSONTokener tokener = new JSONTokener(bufferedReader);
+        JSONObject json = new JSONObject(tokener);
+
+        assertNotNull(json);
+        assertEquals("John", json.get("name"));
+        assertEquals(18, json.get("age"));
+    }
+
+    @Test
+    public void givenValidJson_whenUsingString_thenJSONObjectConverts() throws IOException {
+        byte[] b = "{ \"name\" : \"John\", \"age\" : 18 }".getBytes(StandardCharsets.UTF_8);
+        InputStream is = new ByteArrayInputStream(b);
+        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(is));
+        StringBuilder sb = new StringBuilder();
+        String line;
+        while ((line = bufferedReader.readLine()) != null) {
+            sb.append(line);
+        }
+        JSONObject json = new JSONObject(sb.toString());
+
+        assertNotNull(json);
+        assertEquals("John", json.get("name"));
+        assertEquals(18, json.get("age"));
+    }
+}

core-java-modules/core-java-jvm/src/test/java/com/baeldung/error/oom/ExecutorServiceUnitTest.java

@@ -0,0 +1,40 @@
+package com.baeldung.error.oom;
+
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ThreadPoolExecutor;
+import java.util.concurrent.TimeUnit;
+import java.util.stream.IntStream;
+
+import org.junit.jupiter.api.Test;
+
+public class ExecutorServiceUnitTest {
+
+    @Test
+    public void givenAnExecutorService_WhenMoreTasksSubmitted_ThenAdditionalTasksWait() {
+
+        // Given
+        int noOfThreads = 5;
+        ExecutorService executorService = Executors.newFixedThreadPool(noOfThreads);
+
+        Runnable runnableTask = () -> {
+            try {
+                TimeUnit.HOURS.sleep(1);
+            } catch (InterruptedException e) {
+                e.printStackTrace();
+            }
+        };
+
+        // When
+        IntStream.rangeClosed(1, 10)
+            .forEach(i -> executorService.submit(runnableTask));
+
+        // Then
+        assertThat(((ThreadPoolExecutor) executorService).getQueue()
+            .size(), is(equalTo(5)));
+    }
+}

core-java-modules/core-java-lang-2/src/main/java/com/baeldung/inttoenum/PizzaStatus.java

@@ -0,0 +1,36 @@
+package com.baeldung.inttoenum;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public enum PizzaStatus {
+    ORDERED(5),
+    READY(2),
+    DELIVERED(0);
+
+    private int timeToDelivery;
+
+    PizzaStatus(int timeToDelivery) {
+        this.timeToDelivery = timeToDelivery;
+    }
+
+    public int getTimeToDelivery() {
+        return timeToDelivery;
+    }
+
+    private static Map<Integer, PizzaStatus> timeToDeliveryToEnumValuesMapping = new HashMap<>();
+
+    static {
+        PizzaStatus[] pizzaStatuses = PizzaStatus.values();
+        for (int pizzaStatusIndex = 0; pizzaStatusIndex < pizzaStatuses.length; pizzaStatusIndex++) {
+            timeToDeliveryToEnumValuesMapping.put(
+                pizzaStatuses[pizzaStatusIndex].getTimeToDelivery(),
+                pizzaStatuses[pizzaStatusIndex]
+            );
+        }
+    }
+
+    public static PizzaStatus castIntToEnum(int timeToDelivery) {
+        return timeToDeliveryToEnumValuesMapping.get(timeToDelivery);
+    }
+}

core-java-modules/core-java-lang-2/src/test/java/com/baeldung/inttoenum/IntToEnumUnitTest.java

@@ -0,0 +1,27 @@
+package com.baeldung.inttoenum;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+public class IntToEnumUnitTest {
+
+    @Test
+    public void whenIntToEnumUsingValuesMethod_thenReturnEnumObject() {
+        int timeToDeliveryForOrderedPizzaStatus = 5;
+        PizzaStatus[] pizzaStatuses = PizzaStatus.values();
+        PizzaStatus pizzaOrderedStatus = null;
+        for (int pizzaStatusIndex = 0; pizzaStatusIndex < pizzaStatuses.length; pizzaStatusIndex++) {
+            if (pizzaStatuses[pizzaStatusIndex].getTimeToDelivery() == timeToDeliveryForOrderedPizzaStatus) {
+                pizzaOrderedStatus = pizzaStatuses[pizzaStatusIndex];
+            }
+        }
+        assertEquals(pizzaOrderedStatus, PizzaStatus.ORDERED);
+    }
+
+    @Test
+    public void whenIntToEnumUsingMap_thenReturnEnumObject() {
+        int timeToDeliveryForOrderedPizzaStatus = 5;
+        assertEquals(PizzaStatus.castIntToEnum(timeToDeliveryForOrderedPizzaStatus), PizzaStatus.ORDERED);
+    }
+}

core-java-modules/core-java-lang-oop-generics/src/main/java/com/baeldung/supertype/TypeReference.java

@@ -0,0 +1,18 @@
+package com.baeldung.supertype;
+
+import java.lang.reflect.ParameterizedType;
+import java.lang.reflect.Type;
+
+public abstract class TypeReference<T> {
+
+    private final Type type;
+
+    public TypeReference() {
+        Type superclass = getClass().getGenericSuperclass();
+        type = ((ParameterizedType) superclass).getActualTypeArguments()[0];
+    }
+
+    public Type getType() {
+        return type;
+    }
+}

core-java-modules/core-java-lang-oop-generics/src/test/java/com/baeldung/supertype/TypeReferenceUnitTest.java

@@ -0,0 +1,24 @@
+package com.baeldung.supertype;
+
+import org.junit.Test;
+
+import java.lang.reflect.ParameterizedType;
+import java.lang.reflect.Type;
+import java.util.Map;
+
+import static org.junit.Assert.assertEquals;
+
+public class TypeReferenceUnitTest {
+
+    @Test
+    public void givenGenericToken_whenUsingSuperTypeToken_thenPreservesTheTypeInfo() {
+        TypeReference<Map<String, Integer>> token = new TypeReference<Map<String, Integer>>() {};
+        Type type = token.getType();
+
+        assertEquals("java.util.Map<java.lang.String, java.lang.Integer>", type.getTypeName());
+
+        Type[] typeArguments = ((ParameterizedType) type).getActualTypeArguments();
+        assertEquals("java.lang.String", typeArguments[0].getTypeName());
+        assertEquals("java.lang.Integer", typeArguments[1].getTypeName());
+    }
+}

core-kotlin-modules/core-kotlin-2/src/test/kotlin/com/baeldung/nullassertion/NotNullAssertionUnitTest.kt

@@ -0,0 +1,20 @@
+package com.baeldung.nullassertion
+
+import org.junit.Test
+import kotlin.test.assertEquals
+
+class NotNullAssertionUnitTest {
+
+    @Test
+    fun givenNullableValue_WhenNotNull_ShouldExtractTheValue() {
+        val answer: String? = "42"
+
+        assertEquals(42, answer!!.toInt())
+    }
+
+    @Test(expected = KotlinNullPointerException::class)
+    fun givenNullableValue_WhenIsNull_ThenShouldThrow() {
+        val noAnswer: String? = null
+        noAnswer!!
+    }
+}

core-kotlin-modules/core-kotlin-strings/src/test/kotlin/com/baeldung/stringcomparison/StringComparisonTest.kt

@@ -19,9 +19,9 @@ class StringComparisonUnitTest {
     fun `compare using referential equals operator`() {
         val first = "kotlin"
         val second = "kotlin"
-        val copyOfFirst = buildString { "kotlin" }
+        val third = String("kotlin".toCharArray())
         assertTrue { first === second }
-        assertFalse { first === copyOfFirst }
+        assertFalse { first === third }
     }
 
     @Test

jee-kotlin/pom.xml

@@ -221,6 +221,7 @@
                             <systemPropertyVariables>
                                 <java.util.logging.manager>org.jboss.logmanager.LogManager</java.util.logging.manager>
                                 <jboss.home>${project.basedir}/target/wildfly-${wildfly.version}</jboss.home>
+                                <jboss.http.port>8756</jboss.http.port>
                                 <module.path>${project.basedir}/target/wildfly-${wildfly.version}/modules</module.path>
                             </systemPropertyVariables>
                             <redirectTestOutputToFile>false</redirectTestOutputToFile>
@@ -278,9 +279,10 @@
         <arquillian-drone-bom.version>2.0.1.Final</arquillian-drone-bom.version>
         <arquillian-rest-client.version>1.0.0.Alpha4</arquillian-rest-client.version>
 
+        <logback.version>1.1.7</logback.version>
+
         <resteasy.version>3.8.0.Final</resteasy.version>
         <shrinkwrap.version>3.1.3</shrinkwrap.version>
-
     </properties>
 
 </project>

jee-kotlin/src/main/resources/META-INF/persistence.xml

@@ -7,7 +7,7 @@
 
     <jta-data-source>java:jboss/datasources/ExampleDS</jta-data-source>
 
-    <class>com.enpy.entity.Student</class>
+    <class>com.baeldung.jeekotlin.entity.Student</class>
 
     <properties>
       <property name="hibernate.hbm2ddl.auto" value="create"/>

jhipster/jhipster-uaa/gateway/src/main/java/com/baeldung/jhipster/gateway/web/rest/errors/ExceptionTranslator.java

@@ -14,6 +14,7 @@ import org.zalando.problem.Problem;
 import org.zalando.problem.ProblemBuilder;
 import org.zalando.problem.Status;
 import org.zalando.problem.spring.web.advice.ProblemHandling;
+import org.zalando.problem.spring.web.advice.security.SecurityAdviceTrait;
 import org.zalando.problem.violations.ConstraintViolationProblem;
 
 import javax.annotation.Nonnull;
@@ -28,7 +29,7 @@ import java.util.stream.Collectors;
  * The error response follows RFC7807 - Problem Details for HTTP APIs (https://tools.ietf.org/html/rfc7807)
  */
 @ControllerAdvice
-public class ExceptionTranslator implements ProblemHandling {
+public class ExceptionTranslator implements ProblemHandling, SecurityAdviceTrait {
 
     /**
      * Post-process the Problem payload to add the message key for the front-end if needed

jhipster/jhipster-uaa/quotes/src/main/java/com/baeldung/jhipster/quotes/web/rest/errors/ExceptionTranslator.java

@@ -14,6 +14,7 @@ import org.zalando.problem.Problem;
 import org.zalando.problem.ProblemBuilder;
 import org.zalando.problem.Status;
 import org.zalando.problem.spring.web.advice.ProblemHandling;
+import org.zalando.problem.spring.web.advice.security.SecurityAdviceTrait;
 import org.zalando.problem.violations.ConstraintViolationProblem;
 
 import javax.annotation.Nonnull;
@@ -28,7 +29,7 @@ import java.util.stream.Collectors;
  * The error response follows RFC7807 - Problem Details for HTTP APIs (https://tools.ietf.org/html/rfc7807)
  */
 @ControllerAdvice
-public class ExceptionTranslator implements ProblemHandling {
+public class ExceptionTranslator implements ProblemHandling, SecurityAdviceTrait {
 
     /**
      * Post-process the Problem payload to add the message key for the front-end if needed

jhipster/jhipster-uaa/uaa/src/main/java/com/baeldung/jhipster/uaa/web/rest/errors/ExceptionTranslator.java

@@ -14,6 +14,7 @@ import org.zalando.problem.Problem;
 import org.zalando.problem.ProblemBuilder;
 import org.zalando.problem.Status;
 import org.zalando.problem.spring.web.advice.ProblemHandling;
+import org.zalando.problem.spring.web.advice.security.SecurityAdviceTrait;
 import org.zalando.problem.violations.ConstraintViolationProblem;
 
 import javax.annotation.Nonnull;
@@ -28,7 +29,7 @@ import java.util.stream.Collectors;
  * The error response follows RFC7807 - Problem Details for HTTP APIs (https://tools.ietf.org/html/rfc7807)
  */
 @ControllerAdvice
-public class ExceptionTranslator implements ProblemHandling {
+public class ExceptionTranslator implements ProblemHandling, SecurityAdviceTrait {
 
     /**
      * Post-process the Problem payload to add the message key for the front-end if needed

jmh/src/main/java/com/baeldung/BenchMark.java

@@ -1,14 +1,20 @@
 package com.baeldung;
 
-import com.google.common.hash.HashFunction;
 import com.google.common.hash.Hasher;
 import com.google.common.hash.Hashing;
 import org.openjdk.jmh.annotations.*;
+import org.openjdk.jmh.infra.Blackhole;
 
 import java.nio.charset.Charset;
+import java.util.concurrent.TimeUnit;
 
 public class BenchMark {
 
+    @State(Scope.Benchmark)
+    public static class Log {
+        public int x = 8;
+    }
+
     @State(Scope.Benchmark)
     public static class ExecutionPlan {
 
@@ -45,4 +51,44 @@ public class BenchMark {
         // Do nothing
     }
 
+    @Benchmark
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    @BenchmarkMode(Mode.AverageTime)
+    public void doNothing() {
+
+    }
+
+    @Benchmark
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    @BenchmarkMode(Mode.AverageTime)
+    public void objectCreation() {
+        new Object();
+    }
+
+    @Benchmark
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    @BenchmarkMode(Mode.AverageTime)
+    public Object pillarsOfCreation() {
+        return new Object();
+    }
+
+    @Benchmark
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    @BenchmarkMode(Mode.AverageTime)
+    public void blackHole(Blackhole blackhole) {
+        blackhole.consume(new Object());
+    }
+
+    @Benchmark
+    public double foldedLog() {
+        int x = 8;
+
+        return Math.log(x);
+    }
+
+    @Benchmark
+    public double log(Log input) {
+        return Math.log(input.x);
+    }
+
 }

language-interop/README.md

@@ -3,3 +3,5 @@
 This module contains articles about Java interop with other language integrations.  
 
 ### Relevant Articles:
+
+- [How to Call Python From Java](https://www.baeldung.com/java-working-with-python)

libraries-data-2/pom.xml

@@ -121,6 +121,11 @@
             <artifactId>univocity-parsers</artifactId>
             <version>${univocity.version}</version>
         </dependency>
+        <dependency>
+            <groupId>org.apache.kafka</groupId>
+            <artifactId>kafka-clients</artifactId>
+            <version>${kafka.version}</version>
+        </dependency>
         <dependency>
             <groupId>org.awaitility</groupId>
             <artifactId>awaitility</artifactId>
@@ -184,6 +189,7 @@
         <renjin.version>RELEASE</renjin.version>
         <rcaller.version>3.0</rcaller.version>
         <rserve.version>1.8.1</rserve.version>
+        <kafka.version>2.5.0</kafka.version>
     </properties>
 
     <build>

libraries-data-2/src/main/java/com/baeldung/kafka/consumer/CountryPopulation.java

@@ -0,0 +1,28 @@
+package com.baeldung.kafka.consumer;
+
+class CountryPopulation {
+
+    private String country;
+    private Integer population;
+
+    public CountryPopulation(String country, Integer population) {
+        this.country = country;
+        this.population = population;
+    }
+
+    public String getCountry() {
+        return country;
+    }
+
+    public void setCountry(String country) {
+        this.country = country;
+    }
+
+    public Integer getPopulation() {
+        return population;
+    }
+
+    public void setPopulation(Integer population) {
+        this.population = population;
+    }
+}

libraries-data-2/src/main/java/com/baeldung/kafka/consumer/CountryPopulationConsumer.java

@@ -0,0 +1,60 @@
+package com.baeldung.kafka.consumer;
+
+import java.time.Duration;
+import java.util.Collections;
+import java.util.stream.StreamSupport;
+
+import org.apache.kafka.clients.consumer.Consumer;
+import org.apache.kafka.clients.consumer.ConsumerRecords;
+import org.apache.kafka.common.TopicPartition;
+import org.apache.kafka.common.errors.WakeupException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class CountryPopulationConsumer {
+
+    private static Logger logger = LoggerFactory.getLogger(CountryPopulationConsumer.class);
+
+    private Consumer<String, Integer> consumer;
+    private java.util.function.Consumer<Throwable> exceptionConsumer;
+    private java.util.function.Consumer<CountryPopulation> countryPopulationConsumer;
+
+    public CountryPopulationConsumer(
+            Consumer<String, Integer> consumer, java.util.function.Consumer<Throwable> exceptionConsumer,
+            java.util.function.Consumer<CountryPopulation> countryPopulationConsumer) {
+        this.consumer = consumer;
+        this.exceptionConsumer = exceptionConsumer;
+        this.countryPopulationConsumer = countryPopulationConsumer;
+    }
+
+    void startBySubscribing(String topic) {
+        consume(() -> consumer.subscribe(Collections.singleton(topic)));
+    }
+
+    void startByAssigning(String topic, int partition) {
+        consume(() -> consumer.assign(Collections.singleton(new TopicPartition(topic, partition))));
+    }
+
+    private void consume(Runnable beforePollingTask) {
+        try {
+            beforePollingTask.run();
+            while (true) {
+                ConsumerRecords<String, Integer> records = consumer.poll(Duration.ofMillis(1000));
+                StreamSupport.stream(records.spliterator(), false)
+                    .map(record -> new CountryPopulation(record.key(), record.value()))
+                    .forEach(countryPopulationConsumer);
+                consumer.commitSync();
+            }
+        } catch (WakeupException e) {
+            logger.info("Shutting down...");
+        } catch (RuntimeException ex) {
+            exceptionConsumer.accept(ex);
+        } finally {
+            consumer.close();
+        }
+    }
+
+    public void stop() {
+        consumer.wakeup();
+    }
+}

libraries-data-2/src/test/java/com/baeldung/kafka/consumer/CountryPopulationConsumerUnitTest.java

@@ -0,0 +1,100 @@
+package com.baeldung.kafka.consumer;
+
+import static org.assertj.core.api.AssertionsForInterfaceTypes.assertThat;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+
+import org.apache.kafka.clients.consumer.ConsumerRecord;
+import org.apache.kafka.clients.consumer.MockConsumer;
+import org.apache.kafka.clients.consumer.OffsetResetStrategy;
+import org.apache.kafka.common.KafkaException;
+import org.apache.kafka.common.TopicPartition;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+class CountryPopulationConsumerUnitTest {
+
+    private static final String TOPIC = "topic";
+    private static final int PARTITION = 0;
+
+    private CountryPopulationConsumer countryPopulationConsumer;
+
+    private List<CountryPopulation> updates;
+    private Throwable pollException;
+
+    private MockConsumer<String, Integer> consumer;
+
+    @BeforeEach
+    void setUp() {
+        consumer = new MockConsumer<>(OffsetResetStrategy.EARLIEST);
+        updates = new ArrayList<>();
+        countryPopulationConsumer = new CountryPopulationConsumer(consumer, ex -> this.pollException = ex, updates::add);
+    }
+
+    @Test
+    void whenStartingByAssigningTopicPartition_thenExpectUpdatesAreConsumedCorrectly() {
+        // GIVEN
+        consumer.schedulePollTask(() -> consumer.addRecord(record(TOPIC, PARTITION, "Romania", 19_410_000)));
+        consumer.schedulePollTask(() -> countryPopulationConsumer.stop());
+
+        HashMap<TopicPartition, Long> startOffsets = new HashMap<>();
+        TopicPartition tp = new TopicPartition(TOPIC, PARTITION);
+        startOffsets.put(tp, 0L);
+        consumer.updateBeginningOffsets(startOffsets);
+
+        // WHEN
+        countryPopulationConsumer.startByAssigning(TOPIC, PARTITION);
+
+        // THEN
+        assertThat(updates).hasSize(1);
+        assertThat(consumer.closed()).isTrue();
+    }
+
+    @Test
+    void whenStartingBySubscribingToTopic_thenExpectUpdatesAreConsumedCorrectly() {
+        // GIVEN
+        consumer.schedulePollTask(() -> {
+            consumer.rebalance(Collections.singletonList(new TopicPartition(TOPIC, 0)));
+            consumer.addRecord(record(TOPIC, PARTITION, "Romania", 19_410_000));
+        });
+        consumer.schedulePollTask(() -> countryPopulationConsumer.stop());
+
+        HashMap<TopicPartition, Long> startOffsets = new HashMap<>();
+        TopicPartition tp = new TopicPartition(TOPIC, PARTITION);
+        startOffsets.put(tp, 0L);
+        consumer.updateBeginningOffsets(startOffsets);
+
+        // WHEN
+        countryPopulationConsumer.startBySubscribing(TOPIC);
+
+        // THEN
+        assertThat(updates).hasSize(1);
+        assertThat(consumer.closed()).isTrue();
+    }
+
+    @Test
+    void whenStartingBySubscribingToTopicAndExceptionOccurs_thenExpectExceptionIsHandledCorrectly() {
+        // GIVEN
+        consumer.schedulePollTask(() -> consumer.setPollException(new KafkaException("poll exception")));
+        consumer.schedulePollTask(() -> countryPopulationConsumer.stop());
+
+        HashMap<TopicPartition, Long> startOffsets = new HashMap<>();
+        TopicPartition tp = new TopicPartition(TOPIC, 0);
+        startOffsets.put(tp, 0L);
+        consumer.updateBeginningOffsets(startOffsets);
+
+        // WHEN
+        countryPopulationConsumer.startBySubscribing(TOPIC);
+
+        // THEN
+        assertThat(pollException).isInstanceOf(KafkaException.class).hasMessage("poll exception");
+        assertThat(consumer.closed()).isTrue();
+    }
+
+    private ConsumerRecord<String, Integer> record(String topic, int partition, String country, int population) {
+        return new ConsumerRecord<>(topic, partition, 0, country, population);
+    }
+}

libraries-data-db/pom.xml

@@ -211,7 +211,7 @@
         <datanucleus-maven-plugin.version>5.0.2</datanucleus-maven-plugin.version>
         <datanucleus-jdo-query.version>5.0.4</datanucleus-jdo-query.version>
         <javax.jdo.version>3.2.0-m7</javax.jdo.version>
-        <HikariCP.version>2.7.2</HikariCP.version>
+        <HikariCP.version>3.4.5</HikariCP.version>
         <ebean.version>11.22.4</ebean.version>
     </properties>
 

libraries-rpc/README.md

@@ -0,0 +1,3 @@
+### Relevant Articles:
+
+- [Introduction to Finagle](https://www.baeldung.com/java-finagle)

libraries-server-2/.gitignore

@@ -0,0 +1,9 @@
+*.class
+
+# Folders #
+/gensrc
+/target
+
+# Packaged files #
+*.jar
+/bin/

libraries-server-2/README.md

@@ -0,0 +1,8 @@
+## Server
+
+This module contains articles about server libraries.
+
+### Relevant Articles:
+
+- [HTTP/2 in Jetty](https://www.baeldung.com/jetty-http-2)
+- More articles: [[<-- prev]](../libraries-server)

libraries-server-2/pom.xml

@@ -0,0 +1,77 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <artifactId>libraries-server-2</artifactId>
+    <version>0.0.1-SNAPSHOT</version>
+    <name>libraries-server-2</name>
+    <packaging>war</packaging>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.eclipse.jetty</groupId>
+            <artifactId>jetty-server</artifactId>
+            <version>${jetty.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.eclipse.jetty</groupId>
+            <artifactId>jetty-servlet</artifactId>
+            <version>${jetty.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.eclipse.jetty</groupId>
+            <artifactId>jetty-webapp</artifactId>
+            <version>${jetty.version}</version>
+        </dependency>
+    </dependencies>
+    
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.eclipse.jetty</groupId>
+                <artifactId>jetty-maven-plugin</artifactId>
+                <version>${jetty.version}</version>
+                <configuration>
+                    <stopPort>8888</stopPort>
+                    <stopKey>quit</stopKey>
+                    <jvmArgs>
+                        -Xbootclasspath/p:${settings.localRepository}/org/mortbay/jetty/alpn/alpn-boot/${alpn.version}/alpn-boot-${alpn.version}.jar
+                    </jvmArgs>
+                    <jettyXml>${basedir}/src/main/config/jetty.xml</jettyXml>
+                    <webApp>
+                        <contextPath>/</contextPath>
+                    </webApp>
+                </configuration>
+                <dependencies>
+                    <dependency>
+                        <groupId>org.eclipse.jetty.http2</groupId>
+                        <artifactId>http2-server</artifactId>
+                        <version>${jetty.version}</version>
+                    </dependency>
+                    <dependency>
+                        <groupId>org.eclipse.jetty</groupId>
+                        <artifactId>jetty-alpn-openjdk8-server</artifactId>
+                        <version>${jetty.version}</version>
+                    </dependency>
+                    <dependency>
+                        <groupId>org.eclipse.jetty</groupId>
+                        <artifactId>jetty-servlets</artifactId>
+                        <version>${jetty.version}</version>
+                    </dependency>
+                </dependencies>
+            </plugin>
+        </plugins>
+    </build>
+
+    <properties>
+        <jetty.version>9.4.27.v20200227</jetty.version>
+        <alpn.version>8.1.11.v20170118</alpn.version>
+    </properties>
+
+</project>

libraries-server-2/src/main/resources/logback.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<configuration>
+    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+        <encoder>
+            <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n
+            </pattern>
+        </encoder>
+    </appender>
+
+    <root level="INFO">
+        <appender-ref ref="STDOUT" />
+    </root>
+</configuration>

libraries-server/README.md

@@ -13,4 +13,4 @@ This module contains articles about server libraries.
 - [MQTT Client in Java](https://www.baeldung.com/java-mqtt-client)
 - [Guide to XMPP Smack Client](https://www.baeldung.com/xmpp-smack-chat-client)
 - [A Guide to NanoHTTPD](https://www.baeldung.com/nanohttpd)
-- [HTTP/2 in Jetty](https://www.baeldung.com/jetty-http-2)
+- More articles: [[more -->]](../libraries-server-2)

libraries-server/pom.xml

@@ -5,7 +5,6 @@
     <artifactId>libraries-server</artifactId>
     <version>0.0.1-SNAPSHOT</version>
     <name>libraries-server</name>
-    <packaging>war</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>
@@ -107,50 +106,11 @@
 
     </dependencies>
     
-    <build>
-        <plugins>
-            <plugin>
-                <groupId>org.eclipse.jetty</groupId>
-                <artifactId>jetty-maven-plugin</artifactId>
-                <version>${jetty.version}</version>
-                <configuration>
-                    <stopPort>8888</stopPort>
-                    <stopKey>quit</stopKey>
-                    <jvmArgs>
-                        -Xbootclasspath/p:${settings.localRepository}/org/mortbay/jetty/alpn/alpn-boot/${alpn.version}/alpn-boot-${alpn.version}.jar
-                    </jvmArgs>
-                    <jettyXml>${basedir}/src/main/config/jetty.xml</jettyXml>
-                    <webApp>
-                        <contextPath>/</contextPath>
-                    </webApp>
-                </configuration>
-                <dependencies>
-                    <dependency>
-                        <groupId>org.eclipse.jetty.http2</groupId>
-                        <artifactId>http2-server</artifactId>
-                        <version>${jetty.version}</version>
-                    </dependency>
-                    <dependency>
-                        <groupId>org.eclipse.jetty</groupId>
-                        <artifactId>jetty-alpn-openjdk8-server</artifactId>
-                        <version>${jetty.version}</version>
-                    </dependency>
-                    <dependency>
-                        <groupId>org.eclipse.jetty</groupId>
-                        <artifactId>jetty-servlets</artifactId>
-                        <version>${jetty.version}</version>
-                    </dependency>
-                </dependencies>
-            </plugin>
-        </plugins>
-    </build>
-
     <properties>
         <assertj.version>3.6.2</assertj.version>
         <httpclient.version>4.5.3</httpclient.version>
         <jetty.version>9.4.27.v20200227</jetty.version>
         <netty.version>4.1.20.Final</netty.version>
-        <alpn.version>8.1.11.v20170118</alpn.version>
         <tomcat.version>8.5.24</tomcat.version>
         <smack.version>4.3.1</smack.version>
         <eclipse.paho.client.mqttv3.version>1.2.0</eclipse.paho.client.mqttv3.version>

netflix-modules/genie/README.md

@@ -0,0 +1,3 @@
+### Relevant Articles:
+
+- [Introduction to Netflix Genie](https://www.baeldung.com/netflix-genie-intro)

persistence-modules/hibernate-libraries/src/test/java/com/baeldung/hibernate/types/HibernateTypesLiveTest.java

@@ -13,7 +13,7 @@ import java.util.UUID;
 import static org.assertj.core.api.Assertions.assertThat;
 
 @SpringBootTest
-public class HibernateTypesIntegrationTest {
+public class HibernateTypesLiveTest {
 
     @Autowired
     AlbumRepository albumRepository;

persistence-modules/redis/README.md

@@ -4,3 +4,4 @@
 - [Introduction to Lettuce – the Java Redis Client](https://www.baeldung.com/java-redis-lettuce)
 - [List All Available Redis Keys](https://www.baeldung.com/redis-list-available-keys)
 - [Spring Data Redis’s Property-Based Configuration](https://www.baeldung.com/spring-data-redis-properties)
+- [Delete Everything in Redis](https://www.baeldung.com/redis-delete-data)

persistence-modules/redis/pom.xml

@@ -33,7 +33,8 @@
         <dependency>
             <groupId>redis.clients</groupId>
             <artifactId>jedis</artifactId>
-            </dependency>
+            <version>3.3.0</version>
+        </dependency>
         <dependency>
             <groupId>com.github.kstyrc</groupId>
             <artifactId>embedded-redis</artifactId>

persistence-modules/redis/src/test/java/com/baeldung/redis/deleteeverything/DeleteEverythingInRedisIntegrationTest.java

@@ -0,0 +1,91 @@
+package com.baeldung.redis.deleteeverything;
+
+import org.junit.*;
+import redis.clients.jedis.Jedis;
+import redis.embedded.RedisServer;
+
+import java.io.IOException;
+import java.net.ServerSocket;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
+
+public class DeleteEverythingInRedisIntegrationTest {
+    private Jedis jedis;
+    private RedisServer redisServer;
+    private int port;
+
+    @Before
+    public void setUp() throws IOException {
+
+        // Take an available port
+        ServerSocket s = new ServerSocket(0);
+        port = s.getLocalPort();
+        s.close();
+
+        redisServer = new RedisServer(port);
+        redisServer.start();
+
+        // Configure JEDIS
+        jedis = new Jedis("localhost", port);
+    }
+
+    @After
+    public void destroy() {
+        redisServer.stop();
+    }
+
+    @Test
+    public void whenPutDataIntoRedis_thenCanBeFound() {
+        String key = "key";
+        String value = "value";
+
+        jedis.set(key, value);
+        String received = jedis.get(key);
+
+        assertEquals(value, received);
+    }
+
+    @Test
+    public void whenPutDataIntoRedisAndThenFlush_thenCannotBeFound() {
+        String key = "key";
+        String value = "value";
+
+        jedis.set(key, value);
+
+        jedis.flushDB();
+
+        String received = jedis.get(key);
+
+        assertNull(received);
+    }
+
+    @Test
+    public void whenPutDataIntoMultipleDatabases_thenFlushAllRemovesAll() {
+        // add keys in different databases
+        jedis.select(0);
+        jedis.set("key1", "value1");
+        jedis.select(1);
+        jedis.set("key2", "value2");
+
+        // we'll find the correct keys in the correct dbs
+        jedis.select(0);
+        assertEquals("value1", jedis.get("key1"));
+        assertNull(jedis.get("key2"));
+
+        jedis.select(1);
+        assertEquals("value2", jedis.get("key2"));
+        assertNull(jedis.get("key1"));
+
+        // then, when we flush
+        jedis.flushAll();
+
+        // the keys will have gone
+        jedis.select(0);
+        assertNull(jedis.get("key1"));
+        assertNull(jedis.get("key2"));
+        jedis.select(1);
+        assertNull(jedis.get("key1"));
+        assertNull(jedis.get("key2"));
+    }
+}

persistence-modules/spring-boot-persistence-2/README.md

@@ -3,6 +3,6 @@
 - [Using JDBI with Spring Boot](https://www.baeldung.com/spring-boot-jdbi)
 - [Configuring a Tomcat Connection Pool in Spring Boot](https://www.baeldung.com/spring-boot-tomcat-connection-pool)
 - [Integrating Spring Boot with HSQLDB](https://www.baeldung.com/spring-boot-hsqldb)
-- [List of In-Memory Databases](http://www.baeldung.com/java-in-memory-databases)
+- [List of In-Memory Databases](https://www.baeldung.com/java-in-memory-databases)
 - [Oracle Connection Pooling With Spring](https://www.baeldung.com/spring-oracle-connection-pooling)
 - More articles: [[<-- prev]](../spring-boot-persistence)

persistence-modules/spring-boot-persistence-2/src/test/java/com/baeldung/tomcatconnectionpool/test/application/SpringBootTomcatConnectionPoolIntegrationTest.java

@@ -4,6 +4,7 @@ import javax.sql.DataSource;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.test.context.TestPropertySource;
 import org.springframework.test.context.junit4.SpringRunner;
 
 import com.baeldung.tomcatconnectionpool.application.SpringBootConsoleApplication;
@@ -13,6 +14,7 @@ import org.springframework.boot.test.context.SpringBootTest;
 
 @RunWith(SpringRunner.class)
 @SpringBootTest(classes = {SpringBootConsoleApplication.class})
+@TestPropertySource(properties = "spring.datasource.type=org.apache.tomcat.jdbc.pool.DataSource")
 public class SpringBootTomcatConnectionPoolIntegrationTest {
     
     @Autowired

persistence-modules/spring-boot-persistence-h2/pom.xml

@@ -35,23 +35,21 @@
             <version>${lombok.version}</version>
             <scope>compile</scope>
         </dependency>
-        <dependency>
-            <groupId>org.hibernate</groupId>
-            <artifactId>hibernate-core</artifactId>
-            <version>${hibernate.version}</version>
-        </dependency>
         <dependency>
             <groupId>com.vladmihalcea</groupId>
             <artifactId>db-util</artifactId>
             <version>${db-util.version}</version>
         </dependency>
+        <dependency>
+            <groupId>net.bytebuddy</groupId>
+            <artifactId>byte-buddy</artifactId>
+            <version>${byte-buddy.version}</version>
+        </dependency>
     </dependencies>
 
     <properties>
         <!-- The main class to start by executing java -jar -->
         <start-class>com.baeldung.h2db.demo.server.SpringBootApp</start-class>
-        <spring-boot.version>2.0.4.RELEASE</spring-boot.version>
-        <hibernate.version>5.3.11.Final</hibernate.version>
         <db-util.version>1.0.4</db-util.version>
     </properties>
 

persistence-modules/spring-boot-persistence-h2/src/main/resources/application.properties

@@ -8,5 +8,4 @@ spring.jpa.properties.hibernate.format_sql=true
 spring.jpa.properties.hibernate.validator.apply_to_ddl=false
 #spring.jpa.properties.hibernate.check_nullability=true
 spring.h2.console.enabled=true
-spring.h2.console.path=/h2-console
+spring.h2.console.path=/h2-console
-debug=true

persistence-modules/spring-boot-persistence/README.MD

@@ -1,8 +1,8 @@
 ### Relevant Articles:
 
-- [Spring Boot with Multiple SQL Import Files](http://www.baeldung.com/spring-boot-sql-import-files)
+- [Spring Boot with Multiple SQL Import Files](https://www.baeldung.com/spring-boot-sql-import-files)
-- [Configuring Separate Spring DataSource for Tests](http://www.baeldung.com/spring-testing-separate-data-source)
+- [Configuring Separate Spring DataSource for Tests](https://www.baeldung.com/spring-testing-separate-data-source)
-- [Quick Guide on Loading Initial Data with Spring Boot](http://www.baeldung.com/spring-boot-data-sql-and-schema-sql)
+- [Quick Guide on Loading Initial Data with Spring Boot](https://www.baeldung.com/spring-boot-data-sql-and-schema-sql)
 - [Configuring a DataSource Programmatically in Spring Boot](https://www.baeldung.com/spring-boot-configure-data-source-programmatic)
 - [Resolving “Failed to Configure a DataSource” Error](https://www.baeldung.com/spring-boot-failed-to-configure-data-source)
 - [Hibernate Field Naming with Spring Boot](https://www.baeldung.com/hibernate-field-naming-spring-boot)

persistence-modules/spring-data-elasticsearch/pom.xml

@@ -15,13 +15,7 @@
     <dependencies>
         <dependency>
             <groupId>org.springframework</groupId>
-            <artifactId>spring-core</artifactId>
+            <artifactId>spring-web</artifactId>
-            <version>${spring.version}</version>
-        </dependency>
-
-        <dependency>
-            <groupId>org.springframework</groupId>
-            <artifactId>spring-context</artifactId>
             <version>${spring.version}</version>
         </dependency>
 
@@ -36,6 +30,7 @@
             <artifactId>elasticsearch</artifactId>
             <version>${elasticsearch.version}</version>
         </dependency>
+        
         <dependency>
             <groupId>com.alibaba</groupId>
             <artifactId>fastjson</artifactId>
@@ -49,8 +44,8 @@
         </dependency>
 
         <dependency>
-            <groupId>com.vividsolutions</groupId>
+            <groupId>org.locationtech.jts</groupId>
-            <artifactId>jts</artifactId>
+            <artifactId>jts-core</artifactId>
             <version>${jts.version}</version>
             <exclusions>
                 <exclusion>
@@ -60,41 +55,19 @@
             </exclusions>
         </dependency>
 
-        <dependency>
-            <groupId>org.apache.logging.log4j</groupId>
-            <artifactId>log4j-core</artifactId>
-            <version>${log4j.version}</version>
-        </dependency>
-
-        <dependency>
-            <groupId>org.elasticsearch.client</groupId>
-            <artifactId>transport</artifactId>
-            <version>${elasticsearch.version}</version>
-        </dependency>
-
         <dependency>
             <groupId>org.springframework</groupId>
             <artifactId>spring-test</artifactId>
             <version>${spring.version}</version>
             <scope>test</scope>
         </dependency>
-
-        <dependency>
-            <groupId>net.java.dev.jna</groupId>
-            <artifactId>jna</artifactId>
-            <version>${jna.version}</version>
-            <scope>test</scope>
-        </dependency>
     </dependencies>
 
     <properties>
-        <spring-data-elasticsearch.version>3.0.8.RELEASE</spring-data-elasticsearch.version>
+        <spring-data-elasticsearch.version>4.0.0.RELEASE</spring-data-elasticsearch.version>
-        <jna.version>4.5.2</jna.version>
+        <elasticsearch.version>7.6.2</elasticsearch.version>
-        <elasticsearch.version>5.6.0</elasticsearch.version>
         <fastjson.version>1.2.47</fastjson.version>
-        <spatial4j.version>0.6</spatial4j.version>
+        <spatial4j.version>0.7</spatial4j.version>
-        <jts.version>1.13</jts.version>
+        <jts.version>1.15.0</jts.version>
-        <log4j.version>2.9.1</log4j.version>
     </properties>
-
 </project>

persistence-modules/spring-data-elasticsearch/src/main/java/com/baeldung/spring/data/es/config/Config.java

@@ -1,19 +1,13 @@
 package com.baeldung.spring.data.es.config;
 
-import java.net.InetAddress;
+import org.elasticsearch.client.RestHighLevelClient;
-import java.net.UnknownHostException;
-
-import org.elasticsearch.client.Client;
-import org.elasticsearch.client.transport.TransportClient;
-import org.elasticsearch.common.settings.Settings;
-import org.elasticsearch.common.transport.InetSocketTransportAddress;
-import org.elasticsearch.transport.client.PreBuiltTransportClient;
-import org.springframework.beans.factory.annotation.Value;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.ComponentScan;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.data.elasticsearch.client.ClientConfiguration;
+import org.springframework.data.elasticsearch.client.RestClients;
 import org.springframework.data.elasticsearch.core.ElasticsearchOperations;
-import org.springframework.data.elasticsearch.core.ElasticsearchTemplate;
+import org.springframework.data.elasticsearch.core.ElasticsearchRestTemplate;
 import org.springframework.data.elasticsearch.repository.config.EnableElasticsearchRepositories;
 
 @Configuration
@@ -21,30 +15,18 @@ import org.springframework.data.elasticsearch.repository.config.EnableElasticsea
 @ComponentScan(basePackages = { "com.baeldung.spring.data.es.service" })
 public class Config {
 
-    @Value("${elasticsearch.home:/usr/local/Cellar/elasticsearch/5.6.0}")
-    private String elasticsearchHome;
-
-    @Value("${elasticsearch.cluster.name:elasticsearch}")
-    private String clusterName;
-
     @Bean
-    public Client client() {
+    RestHighLevelClient client() {
-        TransportClient client = null;
+        ClientConfiguration clientConfiguration = ClientConfiguration.builder()
-        try {
+            .connectedTo("localhost:9200")
-            final Settings elasticsearchSettings = Settings.builder()
+            .build();
-              .put("client.transport.sniff", true)
+
-              .put("path.home", elasticsearchHome)
+        return RestClients.create(clientConfiguration)
-              .put("cluster.name", clusterName).build();
+            .rest();
-            client = new PreBuiltTransportClient(elasticsearchSettings);
-            client.addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName("127.0.0.1"), 9300));
-        } catch (UnknownHostException e) {
-            e.printStackTrace();
-        }
-        return client;
     }
 
     @Bean
     public ElasticsearchOperations elasticsearchTemplate() {
-        return new ElasticsearchTemplate(client());
+        return new ElasticsearchRestTemplate(client());
     }
 }

persistence-modules/spring-data-elasticsearch/src/main/java/com/baeldung/spring/data/es/model/Author.java

@@ -1,7 +1,12 @@
 package com.baeldung.spring.data.es.model;
 
+import static org.springframework.data.elasticsearch.annotations.FieldType.Text;
+
+import org.springframework.data.elasticsearch.annotations.Field;
+
 public class Author {
 
+    @Field(type = Text)
     private String name;
 
     public Author() {

persistence-modules/spring-data-elasticsearch/src/main/java/com/baeldung/spring/data/es/service/ArticleService.java

@@ -1,28 +0,0 @@
-package com.baeldung.spring.data.es.service;
-
-import java.util.Optional;
-
-import org.springframework.data.domain.Page;
-import org.springframework.data.domain.Pageable;
-
-import com.baeldung.spring.data.es.model.Article;
-
-public interface ArticleService {
-    Article save(Article article);
-
-    Optional<Article> findOne(String id);
-
-    Iterable<Article> findAll();
-
-    Page<Article> findByAuthorName(String name, Pageable pageable);
-
-    Page<Article> findByAuthorNameUsingCustomQuery(String name, Pageable pageable);
-
-    Page<Article> findByFilteredTagQuery(String tag, Pageable pageable);
-
-    Page<Article> findByAuthorsNameAndFilteredTagQuery(String name, String tag, Pageable pageable);
-
-    long count();
-
-    void delete(Article article);
-}

persistence-modules/spring-data-elasticsearch/src/main/java/com/baeldung/spring/data/es/service/ArticleServiceImpl.java

@@ -1,67 +0,0 @@
-package com.baeldung.spring.data.es.service;
-
-import java.util.Optional;
-
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.data.domain.Page;
-import org.springframework.data.domain.Pageable;
-import org.springframework.stereotype.Service;
-
-import com.baeldung.spring.data.es.model.Article;
-import com.baeldung.spring.data.es.repository.ArticleRepository;
-
-@Service
-public class ArticleServiceImpl implements ArticleService {
-
-    private final ArticleRepository articleRepository;
-    
-    @Autowired
-    public ArticleServiceImpl(ArticleRepository articleRepository) {
-        this.articleRepository = articleRepository;
-    }
-
-    @Override
-    public Article save(Article article) {
-        return articleRepository.save(article);
-    }
-
-    @Override
-    public Optional<Article> findOne(String id) {
-        return articleRepository.findById(id);
-    }
-
-    @Override
-    public Iterable<Article> findAll() {
-        return articleRepository.findAll();
-    }
-
-    @Override
-    public Page<Article> findByAuthorName(String name, Pageable pageable) {
-        return articleRepository.findByAuthorsName(name, pageable);
-    }
-
-    @Override
-    public Page<Article> findByAuthorNameUsingCustomQuery(String name, Pageable pageable) {
-        return articleRepository.findByAuthorsNameUsingCustomQuery(name, pageable);
-    }
-
-    @Override
-    public Page<Article> findByFilteredTagQuery(String tag, Pageable pageable) {
-        return articleRepository.findByFilteredTagQuery(tag, pageable);
-    }
-
-    @Override
-    public Page<Article> findByAuthorsNameAndFilteredTagQuery(String name, String tag, Pageable pageable) {
-        return articleRepository.findByAuthorsNameAndFilteredTagQuery(name, tag, pageable);
-    }
-
-    @Override
-    public long count() {
-        return articleRepository.count();
-    }
-
-    @Override
-    public void delete(Article article) {
-        articleRepository.delete(article);
-    }
-}

persistence-modules/spring-data-elasticsearch/src/test/java/com/baeldung/SpringContextManualTest.java

@@ -8,10 +8,10 @@ import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
 import com.baeldung.spring.data.es.config.Config;
 
 /**
+ * This Manual test requires: Elasticsearch instance running on localhost:9200.
  * 
- * This Manual test requires:
+ * The following docker command can be used: docker run -d --name es762 -p
- * * Elasticsearch instance running on host
+ * 9200:9200 -e "discovery.type=single-node" elasticsearch:7.6.2
- *
  */
 @RunWith(SpringJUnit4ClassRunner.class)
 @ContextConfiguration(classes = Config.class)

persistence-modules/spring-data-elasticsearch/src/test/java/com/baeldung/elasticsearch/ElasticSearchManualTest.java

@@ -3,43 +3,48 @@ package com.baeldung.elasticsearch;
 import static org.junit.Assert.assertEquals;
 
 import java.io.IOException;
-import java.net.InetAddress;
 import java.net.UnknownHostException;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Date;
 import java.util.List;
 import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+import com.alibaba.fastjson.JSON;
 
 import org.elasticsearch.action.DocWriteResponse.Result;
+import org.elasticsearch.action.delete.DeleteRequest;
 import org.elasticsearch.action.delete.DeleteResponse;
+import org.elasticsearch.action.get.GetRequest;
+import org.elasticsearch.action.get.GetResponse;
+import org.elasticsearch.action.index.IndexRequest;
 import org.elasticsearch.action.index.IndexResponse;
+import org.elasticsearch.action.search.SearchRequest;
 import org.elasticsearch.action.search.SearchResponse;
 import org.elasticsearch.action.search.SearchType;
-import org.elasticsearch.client.Client;
+import org.elasticsearch.client.RequestOptions;
-import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.client.RestHighLevelClient;
-import org.elasticsearch.common.transport.InetSocketTransportAddress;
 import org.elasticsearch.common.xcontent.XContentBuilder;
 import org.elasticsearch.common.xcontent.XContentFactory;
 import org.elasticsearch.common.xcontent.XContentType;
 import org.elasticsearch.index.query.QueryBuilders;
 import org.elasticsearch.search.SearchHit;
-import org.elasticsearch.transport.client.PreBuiltTransportClient;
+import org.elasticsearch.search.builder.SearchSourceBuilder;
 import org.junit.Before;
 import org.junit.Test;
-
+import org.springframework.data.elasticsearch.client.ClientConfiguration;
-import com.alibaba.fastjson.JSON;
+import org.springframework.data.elasticsearch.client.RestClients;
 
 /**
+ * This Manual test requires: Elasticsearch instance running on localhost:9200.
  * 
- * This Manual test requires:
+ * The following docker command can be used: docker run -d --name es762 -p
- * * Elasticsearch instance running on host
+ * 9200:9200 -e "discovery.type=single-node" elasticsearch:7.6.2
- * * with cluster name = elasticsearch
- *
  */
 public class ElasticSearchManualTest {
     private List<Person> listOfPersons = new ArrayList<>();
-    private Client client = null;
+    private RestHighLevelClient client = null;
 
     @Before
     public void setUp() throws UnknownHostException {
@@ -47,115 +52,122 @@ public class ElasticSearchManualTest {
         Person person2 = new Person(25, "Janette Doe", new Date());
         listOfPersons.add(person1);
         listOfPersons.add(person2);
-        
+
-        client = new PreBuiltTransportClient(Settings.builder().put("client.transport.sniff", true)
+        ClientConfiguration clientConfiguration = ClientConfiguration.builder()
-            .put("cluster.name","elasticsearch").build())
+            .connectedTo("localhost:9200")
-            .addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName("127.0.0.1"), 9300));
+            .build();
+        client = RestClients.create(clientConfiguration)
+            .rest();
     }
 
     @Test
-    public void givenJsonString_whenJavaObject_thenIndexDocument() {
+    public void givenJsonString_whenJavaObject_thenIndexDocument() throws Exception {
         String jsonObject = "{\"age\":20,\"dateOfBirth\":1471466076564,\"fullName\":\"John Doe\"}";
-        IndexResponse response = client
+        IndexRequest request = new IndexRequest("people");
-          .prepareIndex("people", "Doe")
+        request.source(jsonObject, XContentType.JSON);
-          .setSource(jsonObject, XContentType.JSON)
+
-          .get();
+        IndexResponse response = client.index(request, RequestOptions.DEFAULT);
         String index = response.getIndex();
-        String type = response.getType();
+        long version = response.getVersion();
 
         assertEquals(Result.CREATED, response.getResult());
-        assertEquals(index, "people");
+        assertEquals(1, version);
-        assertEquals(type, "Doe");
+        assertEquals("people", index);
     }
 
     @Test
-    public void givenDocumentId_whenJavaObject_thenDeleteDocument() {
+    public void givenDocumentId_whenJavaObject_thenDeleteDocument() throws Exception {
         String jsonObject = "{\"age\":10,\"dateOfBirth\":1471455886564,\"fullName\":\"Johan Doe\"}";
-        IndexResponse response = client
+        IndexRequest indexRequest = new IndexRequest("people");
-          .prepareIndex("people", "Doe")
+        indexRequest.source(jsonObject, XContentType.JSON);
-          .setSource(jsonObject, XContentType.JSON)
+
-          .get();
+        IndexResponse response = client.index(indexRequest, RequestOptions.DEFAULT);
         String id = response.getId();
-        DeleteResponse deleteResponse = client
-          .prepareDelete("people", "Doe", id)
-          .get();
 
-        assertEquals(Result.DELETED,deleteResponse.getResult());
+        GetRequest getRequest = new GetRequest("people");
+        getRequest.id(id);
+
+        GetResponse getResponse = client.get(getRequest, RequestOptions.DEFAULT);
+        System.out.println(getResponse.getSourceAsString());
+
+        DeleteRequest deleteRequest = new DeleteRequest("people");
+        deleteRequest.id(id);
+
+        DeleteResponse deleteResponse = client.delete(deleteRequest, RequestOptions.DEFAULT);
+
+        assertEquals(Result.DELETED, deleteResponse.getResult());
     }
 
     @Test
-    public void givenSearchRequest_whenMatchAll_thenReturnAllResults() {
+    public void givenSearchRequest_whenMatchAll_thenReturnAllResults() throws Exception {
-        SearchResponse response = client
+        SearchRequest searchRequest = new SearchRequest();
-          .prepareSearch()
+        SearchResponse response = client.search(searchRequest, RequestOptions.DEFAULT);
-          .execute()
+        SearchHit[] searchHits = response.getHits()
-          .actionGet();
+            .getHits();
-        SearchHit[] searchHits = response
-          .getHits()
-          .getHits();
         List<Person> results = Arrays.stream(searchHits)
-          .map(hit -> JSON.parseObject(hit.getSourceAsString(), Person.class))
+            .map(hit -> JSON.parseObject(hit.getSourceAsString(), Person.class))
-          .collect(Collectors.toList());
+            .collect(Collectors.toList());
+
+        results.forEach(System.out::println);
     }
 
     @Test
-    public void givenSearchParameters_thenReturnResults() {
+    public void givenSearchParameters_thenReturnResults() throws Exception {
-        SearchResponse response = client
+        SearchSourceBuilder builder = new SearchSourceBuilder().postFilter(QueryBuilders.rangeQuery("age")
-          .prepareSearch()
-          .setTypes()
-          .setSearchType(SearchType.DFS_QUERY_THEN_FETCH)
-          .setPostFilter(QueryBuilders
-            .rangeQuery("age")
             .from(5)
-            .to(15))
+            .to(15));
-          .setFrom(0)
-          .setSize(60)
-          .setExplain(true)
-          .execute()
-          .actionGet();
 
-        SearchResponse response2 = client
+        SearchRequest searchRequest = new SearchRequest();
-          .prepareSearch()
+        searchRequest.searchType(SearchType.DFS_QUERY_THEN_FETCH);
-          .setTypes()
+        searchRequest.source(builder);
-          .setSearchType(SearchType.DFS_QUERY_THEN_FETCH)
+
-          .setPostFilter(QueryBuilders.simpleQueryStringQuery("+John -Doe OR Janette"))
+        SearchResponse response = client.search(searchRequest, RequestOptions.DEFAULT);
-          .setFrom(0)
+
-          .setSize(60)
+        builder = new SearchSourceBuilder().postFilter(QueryBuilders.simpleQueryStringQuery("+John -Doe OR Janette"));
-          .setExplain(true)
+
-          .execute()
+        searchRequest = new SearchRequest();
-          .actionGet();
+        searchRequest.searchType(SearchType.DFS_QUERY_THEN_FETCH);
+        searchRequest.source(builder);
+
+        SearchResponse response2 = client.search(searchRequest, RequestOptions.DEFAULT);
+
+        builder = new SearchSourceBuilder().postFilter(QueryBuilders.matchQuery("John", "Name*"));
+        searchRequest = new SearchRequest();
+        searchRequest.searchType(SearchType.DFS_QUERY_THEN_FETCH);
+        searchRequest.source(builder);
+
+        SearchResponse response3 = client.search(searchRequest, RequestOptions.DEFAULT);
 
-        SearchResponse response3 = client
-          .prepareSearch()
-          .setTypes()
-          .setSearchType(SearchType.DFS_QUERY_THEN_FETCH)
-          .setPostFilter(QueryBuilders.matchQuery("John", "Name*"))
-          .setFrom(0)
-          .setSize(60)
-          .setExplain(true)
-          .execute()
-          .actionGet();
         response2.getHits();
         response3.getHits();
 
-        final List<Person> results = Arrays.stream(response.getHits().getHits())
+        final List<Person> results = Stream.of(response.getHits()
-          .map(hit -> JSON.parseObject(hit.getSourceAsString(), Person.class))
+            .getHits(),
-          .collect(Collectors.toList());
+            response2.getHits()
+                .getHits(),
+            response3.getHits()
+                .getHits())
+            .flatMap(Arrays::stream)
+            .map(hit -> JSON.parseObject(hit.getSourceAsString(), Person.class))
+            .collect(Collectors.toList());
+
+        results.forEach(System.out::println);
     }
 
     @Test
     public void givenContentBuilder_whenHelpers_thanIndexJson() throws IOException {
-        XContentBuilder builder = XContentFactory
+        XContentBuilder builder = XContentFactory.jsonBuilder()
-          .jsonBuilder()
+            .startObject()
-          .startObject()
+            .field("fullName", "Test")
-          .field("fullName", "Test")
+            .field("salary", "11500")
-          .field("salary", "11500")
+            .field("age", "10")
-          .field("age", "10")
+            .endObject();
-          .endObject();
-        IndexResponse response = client
-          .prepareIndex("people", "Doe")
-          .setSource(builder)
-          .get();
 
-        assertEquals(Result.CREATED, response.getResult());        
+        IndexRequest indexRequest = new IndexRequest("people");
+        indexRequest.source(builder);
+
+        IndexResponse response = client.index(indexRequest, RequestOptions.DEFAULT);
+
+        assertEquals(Result.CREATED, response.getResult());
     }
 }

persistence-modules/spring-data-elasticsearch/src/test/java/com/baeldung/elasticsearch/GeoQueriesManualTest.java

@@ -1,4 +1,5 @@
 package com.baeldung.elasticsearch;
+
 import static org.junit.Assert.assertTrue;
 
 import java.io.IOException;
@@ -7,162 +8,169 @@ import java.util.Arrays;
 import java.util.List;
 import java.util.stream.Collectors;
 
-import org.elasticsearch.action.admin.indices.create.CreateIndexRequest;
+import com.baeldung.spring.data.es.config.Config;
+
+import org.elasticsearch.action.admin.indices.delete.DeleteIndexRequest;
+import org.elasticsearch.action.admin.indices.refresh.RefreshRequest;
+import org.elasticsearch.action.index.IndexRequest;
 import org.elasticsearch.action.index.IndexResponse;
+import org.elasticsearch.action.search.SearchRequest;
 import org.elasticsearch.action.search.SearchResponse;
-import org.elasticsearch.client.Client;
+import org.elasticsearch.client.RequestOptions;
+import org.elasticsearch.client.RestHighLevelClient;
+import org.elasticsearch.client.indices.CreateIndexRequest;
 import org.elasticsearch.common.geo.GeoPoint;
 import org.elasticsearch.common.geo.ShapeRelation;
-import org.elasticsearch.common.geo.builders.ShapeBuilders;
+import org.elasticsearch.common.geo.builders.EnvelopeBuilder;
 import org.elasticsearch.common.unit.DistanceUnit;
 import org.elasticsearch.common.xcontent.XContentType;
+import org.elasticsearch.index.query.GeoShapeQueryBuilder;
 import org.elasticsearch.index.query.QueryBuilder;
 import org.elasticsearch.index.query.QueryBuilders;
 import org.elasticsearch.search.SearchHit;
+import org.elasticsearch.search.builder.SearchSourceBuilder;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
+import org.locationtech.jts.geom.Coordinate;
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.data.elasticsearch.core.ElasticsearchTemplate;
 import org.springframework.test.context.ContextConfiguration;
 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
 
-import com.baeldung.spring.data.es.config.Config;
-import com.vividsolutions.jts.geom.Coordinate;
-
 /**
+ * This Manual test requires: Elasticsearch instance running on localhost:9200.
  * 
- * This Manual test requires:
+ * The following docker command can be used: docker run -d --name es762 -p
- * * Elasticsearch instance running on host
+ * 9200:9200 -e "discovery.type=single-node" elasticsearch:7.6.2
- * * with cluster name = elasticsearch
- * * and further configurations
- *
  */
 @RunWith(SpringJUnit4ClassRunner.class)
 @ContextConfiguration(classes = Config.class)
 public class GeoQueriesManualTest {
 
     private static final String WONDERS_OF_WORLD = "wonders-of-world";
-    private static final String WONDERS = "Wonders";
 
     @Autowired
-    private ElasticsearchTemplate elasticsearchTemplate;
+    private RestHighLevelClient client;
-
-    @Autowired
-    private Client client;
 
     @Before
-    public void setUp() {
+    public void setUp() throws Exception {
-        String jsonObject = "{\"Wonders\":{\"properties\":{\"name\":{\"type\":\"string\",\"index\":\"not_analyzed\"},\"region\":{\"type\":\"geo_shape\",\"tree\":\"quadtree\",\"precision\":\"1m\"},\"location\":{\"type\":\"geo_point\"}}}}";
+        String jsonObject = "{\"properties\":{\"name\":{\"type\":\"text\",\"index\":false},\"region\":{\"type\":\"geo_shape\"},\"location\":{\"type\":\"geo_point\"}}}";
+
         CreateIndexRequest req = new CreateIndexRequest(WONDERS_OF_WORLD);
-        req.mapping(WONDERS, jsonObject, XContentType.JSON);
+        req.mapping(jsonObject, XContentType.JSON);
-        client.admin()
+
-          .indices()
+        client.indices()
-          .create(req)
+            .create(req, RequestOptions.DEFAULT);
-          .actionGet();
     }
 
     @Test
-    public void givenGeoShapeData_whenExecutedGeoShapeQuery_thenResultNonEmpty() throws IOException{
+    public void givenGeoShapeData_whenExecutedGeoShapeQuery_thenResultNonEmpty() throws IOException {
         String jsonObject = "{\"name\":\"Agra\",\"region\":{\"type\":\"envelope\",\"coordinates\":[[75,30.2],[80.1, 25]]}}";
-        IndexResponse response = client.prepareIndex(WONDERS_OF_WORLD, WONDERS)
+        IndexRequest indexRequest = new IndexRequest(WONDERS_OF_WORLD);
-          .setSource(jsonObject, XContentType.JSON)
+        indexRequest.source(jsonObject, XContentType.JSON);
-          .get();
+        IndexResponse response = client.index(indexRequest, RequestOptions.DEFAULT);
-        
+
         String tajMahalId = response.getId();
-        client.admin()
-          .indices()
-          .prepareRefresh(WONDERS_OF_WORLD)
-          .get();
 
-        Coordinate topLeft =new Coordinate(74, 31.2);
+        RefreshRequest refreshRequest = new RefreshRequest(WONDERS_OF_WORLD);
-        Coordinate bottomRight =new Coordinate(81.1, 24);
+        client.indices()
-        QueryBuilder qb = QueryBuilders
+            .refresh(refreshRequest, RequestOptions.DEFAULT);
-            .geoShapeQuery("region", ShapeBuilders.newEnvelope(topLeft, bottomRight))
-            .relation(ShapeRelation.WITHIN);
 
+        Coordinate topLeft = new Coordinate(74, 31.2);
+        Coordinate bottomRight = new Coordinate(81.1, 24);
 
-        SearchResponse searchResponse = client.prepareSearch(WONDERS_OF_WORLD)
+        GeoShapeQueryBuilder qb = QueryBuilders.geoShapeQuery("region", new EnvelopeBuilder(topLeft, bottomRight).buildGeometry());
-          .setTypes(WONDERS)
+        qb.relation(ShapeRelation.INTERSECTS);
-          .setQuery(qb)
+
-          .execute()
+        SearchSourceBuilder source = new SearchSourceBuilder().query(qb);
-          .actionGet();
+        SearchRequest searchRequest = new SearchRequest(WONDERS_OF_WORLD);
+        searchRequest.source(source);
+
+        SearchResponse searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);
 
         List<String> ids = Arrays.stream(searchResponse.getHits()
-          .getHits())
+            .getHits())
-          .map(SearchHit::getId)
+            .map(SearchHit::getId)
-          .collect(Collectors.toList());
+            .collect(Collectors.toList());
 
         assertTrue(ids.contains(tajMahalId));
     }
 
     @Test
-    public void givenGeoPointData_whenExecutedGeoBoundingBoxQuery_thenResultNonEmpty() {
+    public void givenGeoPointData_whenExecutedGeoBoundingBoxQuery_thenResultNonEmpty() throws Exception {
         String jsonObject = "{\"name\":\"Pyramids of Giza\",\"location\":[31.131302,29.976480]}";
-        IndexResponse response = client.prepareIndex(WONDERS_OF_WORLD, WONDERS)
+
-          .setSource(jsonObject, XContentType.JSON)
+        IndexRequest indexRequest = new IndexRequest(WONDERS_OF_WORLD);
-          .get();
+        indexRequest.source(jsonObject, XContentType.JSON);
+        IndexResponse response = client.index(indexRequest, RequestOptions.DEFAULT);
+
         String pyramidsOfGizaId = response.getId();
-        client.admin()
+
-          .indices()
+        RefreshRequest refreshRequest = new RefreshRequest(WONDERS_OF_WORLD);
-          .prepareRefresh(WONDERS_OF_WORLD)
+        client.indices()
-          .get();
+            .refresh(refreshRequest, RequestOptions.DEFAULT);
 
         QueryBuilder qb = QueryBuilders.geoBoundingBoxQuery("location")
-            .setCorners(31,30,28,32);
+            .setCorners(31, 30, 28, 32);
-        
+
-        SearchResponse searchResponse = client.prepareSearch(WONDERS_OF_WORLD)
+        SearchSourceBuilder source = new SearchSourceBuilder().query(qb);
-          .setTypes(WONDERS)
+        SearchRequest searchRequest = new SearchRequest(WONDERS_OF_WORLD);
-          .setQuery(qb)
+        searchRequest.source(source);
-          .execute()
+
-          .actionGet();
+        SearchResponse searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);
+
         List<String> ids = Arrays.stream(searchResponse.getHits()
-          .getHits())
+            .getHits())
-          .map(SearchHit::getId)
+            .map(SearchHit::getId)
-          .collect(Collectors.toList());
+            .collect(Collectors.toList());
         assertTrue(ids.contains(pyramidsOfGizaId));
     }
 
     @Test
-    public void givenGeoPointData_whenExecutedGeoDistanceQuery_thenResultNonEmpty() {
+    public void givenGeoPointData_whenExecutedGeoDistanceQuery_thenResultNonEmpty() throws Exception {
         String jsonObject = "{\"name\":\"Lighthouse of alexandria\",\"location\":[31.131302,29.976480]}";
-        IndexResponse response = client.prepareIndex(WONDERS_OF_WORLD, WONDERS)
+
-          .setSource(jsonObject, XContentType.JSON)
+        IndexRequest indexRequest = new IndexRequest(WONDERS_OF_WORLD);
-          .get();
+        indexRequest.source(jsonObject, XContentType.JSON);
+        IndexResponse response = client.index(indexRequest, RequestOptions.DEFAULT);
+
         String lighthouseOfAlexandriaId = response.getId();
-        client.admin()
+
-          .indices()
+        RefreshRequest refreshRequest = new RefreshRequest(WONDERS_OF_WORLD);
-          .prepareRefresh(WONDERS_OF_WORLD)
+        client.indices()
-          .get();
+            .refresh(refreshRequest, RequestOptions.DEFAULT);
 
         QueryBuilder qb = QueryBuilders.geoDistanceQuery("location")
-          .point(29.976, 31.131)
+            .point(29.976, 31.131)
-          .distance(10, DistanceUnit.MILES);
+            .distance(10, DistanceUnit.MILES);
+
+        SearchSourceBuilder source = new SearchSourceBuilder().query(qb);
+        SearchRequest searchRequest = new SearchRequest(WONDERS_OF_WORLD);
+        searchRequest.source(source);
+
+        SearchResponse searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);
 
-        SearchResponse searchResponse = client.prepareSearch(WONDERS_OF_WORLD)
-          .setTypes(WONDERS)
-          .setQuery(qb)
-          .execute()
-          .actionGet();
         List<String> ids = Arrays.stream(searchResponse.getHits()
-          .getHits())
+            .getHits())
-          .map(SearchHit::getId)
+            .map(SearchHit::getId)
-          .collect(Collectors.toList());
+            .collect(Collectors.toList());
         assertTrue(ids.contains(lighthouseOfAlexandriaId));
     }
 
     @Test
-    public void givenGeoPointData_whenExecutedGeoPolygonQuery_thenResultNonEmpty() {
+    public void givenGeoPointData_whenExecutedGeoPolygonQuery_thenResultNonEmpty() throws Exception {
         String jsonObject = "{\"name\":\"The Great Rann of Kutch\",\"location\":[69.859741,23.733732]}";
-        IndexResponse response = client.prepareIndex(WONDERS_OF_WORLD, WONDERS)
+
-          .setSource(jsonObject, XContentType.JSON)
+        IndexRequest indexRequest = new IndexRequest(WONDERS_OF_WORLD);
-          .get();
+        indexRequest.source(jsonObject, XContentType.JSON);
+        IndexResponse response = client.index(indexRequest, RequestOptions.DEFAULT);
+
         String greatRannOfKutchid = response.getId();
-        client.admin()
+
-          .indices()
+        RefreshRequest refreshRequest = new RefreshRequest(WONDERS_OF_WORLD);
-          .prepareRefresh(WONDERS_OF_WORLD)
+        client.indices()
-          .get();
+            .refresh(refreshRequest, RequestOptions.DEFAULT);
 
         List<GeoPoint> allPoints = new ArrayList<GeoPoint>();
         allPoints.add(new GeoPoint(22.733, 68.859));
@@ -170,20 +178,23 @@ public class GeoQueriesManualTest {
         allPoints.add(new GeoPoint(23, 70.859));
         QueryBuilder qb = QueryBuilders.geoPolygonQuery("location", allPoints);
 
-        SearchResponse searchResponse = client.prepareSearch(WONDERS_OF_WORLD)
+        SearchSourceBuilder source = new SearchSourceBuilder().query(qb);
-          .setTypes(WONDERS)
+        SearchRequest searchRequest = new SearchRequest(WONDERS_OF_WORLD);
-          .setQuery(qb)
+        searchRequest.source(source);
-          .execute()
+
-          .actionGet();
+        SearchResponse searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);
+
         List<String> ids = Arrays.stream(searchResponse.getHits()
-          .getHits())
+            .getHits())
-          .map(SearchHit::getId)
+            .map(SearchHit::getId)
-          .collect(Collectors.toList());
+            .collect(Collectors.toList());
         assertTrue(ids.contains(greatRannOfKutchid));
     }
 
     @After
-    public void destroy() {
+    public void destroy() throws Exception {
-        elasticsearchTemplate.deleteIndex(WONDERS_OF_WORLD);
+        DeleteIndexRequest deleteIndex = new DeleteIndexRequest(WONDERS_OF_WORLD);
+        client.indices()
+            .delete(deleteIndex, RequestOptions.DEFAULT);
     }
 }

persistence-modules/spring-data-elasticsearch/src/test/java/com/baeldung/spring/data/es/ElasticSearchManualTest.java

@@ -10,68 +10,71 @@ import static org.junit.Assert.assertNotNull;
 
 import java.util.List;
 
+import com.baeldung.spring.data.es.config.Config;
+import com.baeldung.spring.data.es.model.Article;
+import com.baeldung.spring.data.es.model.Author;
+import com.baeldung.spring.data.es.repository.ArticleRepository;
+
+import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.PageRequest;
-import org.springframework.data.elasticsearch.core.ElasticsearchTemplate;
+import org.springframework.data.elasticsearch.core.ElasticsearchRestTemplate;
+import org.springframework.data.elasticsearch.core.SearchHits;
+import org.springframework.data.elasticsearch.core.mapping.IndexCoordinates;
 import org.springframework.data.elasticsearch.core.query.NativeSearchQueryBuilder;
-import org.springframework.data.elasticsearch.core.query.SearchQuery;
+import org.springframework.data.elasticsearch.core.query.Query;
 import org.springframework.test.context.ContextConfiguration;
 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
 
-import com.baeldung.spring.data.es.config.Config;
-import com.baeldung.spring.data.es.model.Article;
-import com.baeldung.spring.data.es.model.Author;
-import com.baeldung.spring.data.es.service.ArticleService;
-
 /**
+ * This Manual test requires: Elasticsearch instance running on localhost:9200.
  * 
- * This Manual test requires:
+ * The following docker command can be used: docker run -d --name es762 -p
- * * Elasticsearch instance running on host
+ * 9200:9200 -e "discovery.type=single-node" elasticsearch:7.6.2
- * * with cluster name = elasticsearch
- *
  */
 @RunWith(SpringJUnit4ClassRunner.class)
 @ContextConfiguration(classes = Config.class)
 public class ElasticSearchManualTest {
 
     @Autowired
-    private ElasticsearchTemplate elasticsearchTemplate;
+    private ElasticsearchRestTemplate elasticsearchTemplate;
 
     @Autowired
-    private ArticleService articleService;
+    private ArticleRepository articleRepository;
 
     private final Author johnSmith = new Author("John Smith");
     private final Author johnDoe = new Author("John Doe");
 
     @Before
     public void before() {
-        elasticsearchTemplate.deleteIndex(Article.class);
-        elasticsearchTemplate.createIndex(Article.class);
-        // don't call putMapping() to test the default mappings
-
         Article article = new Article("Spring Data Elasticsearch");
         article.setAuthors(asList(johnSmith, johnDoe));
         article.setTags("elasticsearch", "spring data");
-        articleService.save(article);
+        articleRepository.save(article);
 
         article = new Article("Search engines");
         article.setAuthors(asList(johnDoe));
         article.setTags("search engines", "tutorial");
-        articleService.save(article);
+        articleRepository.save(article);
 
         article = new Article("Second Article About Elasticsearch");
         article.setAuthors(asList(johnSmith));
         article.setTags("elasticsearch", "spring data");
-        articleService.save(article);
+        articleRepository.save(article);
 
         article = new Article("Elasticsearch Tutorial");
         article.setAuthors(asList(johnDoe));
         article.setTags("elasticsearch");
-        articleService.save(article);
+        articleRepository.save(article);
+    }
+
+    @After
+    public void after() {
+        articleRepository.deleteAll();
     }
 
     @Test
@@ -81,82 +84,85 @@ public class ElasticSearchManualTest {
         Article article = new Article("Making Search Elastic");
         article.setAuthors(authors);
 
-        article = articleService.save(article);
+        article = articleRepository.save(article);
         assertNotNull(article.getId());
     }
 
     @Test
     public void givenPersistedArticles_whenSearchByAuthorsName_thenRightFound() {
-
+        final Page<Article> articleByAuthorName = articleRepository.findByAuthorsName(johnSmith.getName(), PageRequest.of(0, 10));
-        final Page<Article> articleByAuthorName = articleService
-          .findByAuthorName(johnSmith.getName(), PageRequest.of(0, 10));
         assertEquals(2L, articleByAuthorName.getTotalElements());
     }
 
     @Test
     public void givenCustomQuery_whenSearchByAuthorsName_thenArticleIsFound() {
-        final Page<Article> articleByAuthorName = articleService.findByAuthorNameUsingCustomQuery("Smith", PageRequest.of(0, 10));
+        final Page<Article> articleByAuthorName = articleRepository.findByAuthorsNameUsingCustomQuery("Smith", PageRequest.of(0, 10));
         assertEquals(2L, articleByAuthorName.getTotalElements());
     }
 
     @Test
     public void givenTagFilterQuery_whenSearchByTag_thenArticleIsFound() {
-        final Page<Article> articleByAuthorName = articleService.findByFilteredTagQuery("elasticsearch", PageRequest.of(0, 10));
+        final Page<Article> articleByAuthorName = articleRepository.findByFilteredTagQuery("elasticsearch", PageRequest.of(0, 10));
         assertEquals(3L, articleByAuthorName.getTotalElements());
     }
 
     @Test
     public void givenTagFilterQuery_whenSearchByAuthorsName_thenArticleIsFound() {
-        final Page<Article> articleByAuthorName = articleService.findByAuthorsNameAndFilteredTagQuery("Doe", "elasticsearch", PageRequest.of(0, 10));
+        final Page<Article> articleByAuthorName = articleRepository.findByAuthorsNameAndFilteredTagQuery("Doe", "elasticsearch", PageRequest.of(0, 10));
         assertEquals(2L, articleByAuthorName.getTotalElements());
     }
 
     @Test
     public void givenPersistedArticles_whenUseRegexQuery_thenRightArticlesFound() {
+        final Query searchQuery = new NativeSearchQueryBuilder().withFilter(regexpQuery("title", ".*data.*"))
+            .build();
 
-        final SearchQuery searchQuery = new NativeSearchQueryBuilder().withFilter(regexpQuery("title", ".*data.*"))
+        final SearchHits<Article> articles = elasticsearchTemplate.search(searchQuery, Article.class, IndexCoordinates.of("blog"));
-          .build();
-        final List<Article> articles = elasticsearchTemplate.queryForList(searchQuery, Article.class);
 
-        assertEquals(1, articles.size());
+        assertEquals(1, articles.getTotalHits());
     }
 
     @Test
     public void givenSavedDoc_whenTitleUpdated_thenCouldFindByUpdatedTitle() {
-        final SearchQuery searchQuery = new NativeSearchQueryBuilder().withQuery(fuzzyQuery("title", "serch")).build();
+        final Query searchQuery = new NativeSearchQueryBuilder().withQuery(fuzzyQuery("title", "serch"))
-        final List<Article> articles = elasticsearchTemplate.queryForList(searchQuery, Article.class);
+            .build();
+        final SearchHits<Article> articles = elasticsearchTemplate.search(searchQuery, Article.class, IndexCoordinates.of("blog"));
 
-        assertEquals(1, articles.size());
+        assertEquals(1, articles.getTotalHits());
 
-        final Article article = articles.get(0);
+        final Article article = articles.getSearchHit(0)
+            .getContent();
         final String newTitle = "Getting started with Search Engines";
         article.setTitle(newTitle);
-        articleService.save(article);
+        articleRepository.save(article);
 
-        assertEquals(newTitle, articleService.findOne(article.getId()).get().getTitle());
+        assertEquals(newTitle, articleRepository.findById(article.getId())
+            .get()
+            .getTitle());
     }
 
     @Test
     public void givenSavedDoc_whenDelete_thenRemovedFromIndex() {
-
         final String articleTitle = "Spring Data Elasticsearch";
 
-        final SearchQuery searchQuery = new NativeSearchQueryBuilder()
+        final Query searchQuery = new NativeSearchQueryBuilder().withQuery(matchQuery("title", articleTitle).minimumShouldMatch("75%"))
-          .withQuery(matchQuery("title", articleTitle).minimumShouldMatch("75%")).build();
+            .build();
-        final List<Article> articles = elasticsearchTemplate.queryForList(searchQuery, Article.class);
+        final SearchHits<Article> articles = elasticsearchTemplate.search(searchQuery, Article.class, IndexCoordinates.of("blog"));
-        assertEquals(1, articles.size());
-        final long count = articleService.count();
 
-        articleService.delete(articles.get(0));
+        assertEquals(1, articles.getTotalHits());
+        final long count = articleRepository.count();
 
-        assertEquals(count - 1, articleService.count());
+        articleRepository.delete(articles.getSearchHit(0)
+            .getContent());
+
+        assertEquals(count - 1, articleRepository.count());
     }
 
     @Test
     public void givenSavedDoc_whenOneTermMatches_thenFindByTitle() {
-        final SearchQuery searchQuery = new NativeSearchQueryBuilder()
+        final Query searchQuery = new NativeSearchQueryBuilder().withQuery(matchQuery("title", "Search engines").operator(AND))
-          .withQuery(matchQuery("title", "Search engines").operator(AND)).build();
+            .build();
-        final List<Article> articles = elasticsearchTemplate.queryForList(searchQuery, Article.class);
+        final SearchHits<Article> articles = elasticsearchTemplate.search(searchQuery, Article.class, IndexCoordinates.of("blog"));
-        assertEquals(1, articles.size());
+        assertEquals(1, articles.getTotalHits());
     }
 }

persistence-modules/spring-data-elasticsearch/src/test/java/com/baeldung/spring/data/es/ElasticSearchQueryManualTest.java

@@ -2,7 +2,6 @@ package com.baeldung.spring.data.es;
 
 import static java.util.Arrays.asList;
 import static java.util.stream.Collectors.toList;
-import static org.elasticsearch.index.query.Operator.AND;
 import static org.elasticsearch.index.query.QueryBuilders.boolQuery;
 import static org.elasticsearch.index.query.QueryBuilders.matchPhraseQuery;
 import static org.elasticsearch.index.query.QueryBuilders.matchQuery;
@@ -14,190 +13,225 @@ import static org.junit.Assert.assertEquals;
 import java.util.List;
 import java.util.Map;
 
+import com.baeldung.spring.data.es.config.Config;
+import com.baeldung.spring.data.es.model.Article;
+import com.baeldung.spring.data.es.model.Author;
+import com.baeldung.spring.data.es.repository.ArticleRepository;
+
 import org.apache.lucene.search.join.ScoreMode;
+import org.elasticsearch.action.search.SearchRequest;
 import org.elasticsearch.action.search.SearchResponse;
-import org.elasticsearch.client.Client;
+import org.elasticsearch.client.RequestOptions;
+import org.elasticsearch.client.RestHighLevelClient;
 import org.elasticsearch.common.unit.Fuzziness;
 import org.elasticsearch.index.query.MultiMatchQueryBuilder;
+import org.elasticsearch.index.query.Operator;
 import org.elasticsearch.index.query.QueryBuilder;
 import org.elasticsearch.search.aggregations.Aggregation;
 import org.elasticsearch.search.aggregations.AggregationBuilders;
+import org.elasticsearch.search.aggregations.BucketOrder;
 import org.elasticsearch.search.aggregations.bucket.MultiBucketsAggregation;
-import org.elasticsearch.search.aggregations.bucket.terms.StringTerms;
+import org.elasticsearch.search.aggregations.bucket.terms.ParsedStringTerms;
-import org.elasticsearch.search.aggregations.bucket.terms.Terms;
 import org.elasticsearch.search.aggregations.bucket.terms.TermsAggregationBuilder;
+import org.elasticsearch.search.builder.SearchSourceBuilder;
+import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.data.elasticsearch.core.ElasticsearchTemplate;
+import org.springframework.data.elasticsearch.core.ElasticsearchRestTemplate;
+import org.springframework.data.elasticsearch.core.SearchHits;
+import org.springframework.data.elasticsearch.core.mapping.IndexCoordinates;
+import org.springframework.data.elasticsearch.core.query.NativeSearchQuery;
 import org.springframework.data.elasticsearch.core.query.NativeSearchQueryBuilder;
-import org.springframework.data.elasticsearch.core.query.SearchQuery;
 import org.springframework.test.context.ContextConfiguration;
 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
 
-import com.baeldung.spring.data.es.config.Config;
-import com.baeldung.spring.data.es.model.Article;
-import com.baeldung.spring.data.es.model.Author;
-import com.baeldung.spring.data.es.service.ArticleService;
-
 /**
+ * This Manual test requires: Elasticsearch instance running on localhost:9200.
  * 
- * This Manual test requires:
+ * The following docker command can be used: docker run -d --name es762 -p
- * * Elasticsearch instance running on host
+ * 9200:9200 -e "discovery.type=single-node" elasticsearch:7.6.2
- * * with cluster name = elasticsearch
- *
  */
 @RunWith(SpringJUnit4ClassRunner.class)
 @ContextConfiguration(classes = Config.class)
 public class ElasticSearchQueryManualTest {
 
     @Autowired
-    private ElasticsearchTemplate elasticsearchTemplate;
+    private ElasticsearchRestTemplate elasticsearchTemplate;
 
     @Autowired
-    private ArticleService articleService;
+    private ArticleRepository articleRepository;
 
     @Autowired
-    private Client client;
+    private RestHighLevelClient client;
 
     private final Author johnSmith = new Author("John Smith");
     private final Author johnDoe = new Author("John Doe");
 
     @Before
     public void before() {
-        elasticsearchTemplate.deleteIndex(Article.class);
-        elasticsearchTemplate.createIndex(Article.class);
-        elasticsearchTemplate.putMapping(Article.class);
-        elasticsearchTemplate.refresh(Article.class);
-
         Article article = new Article("Spring Data Elasticsearch");
         article.setAuthors(asList(johnSmith, johnDoe));
         article.setTags("elasticsearch", "spring data");
-        articleService.save(article);
+        articleRepository.save(article);
 
         article = new Article("Search engines");
         article.setAuthors(asList(johnDoe));
         article.setTags("search engines", "tutorial");
-        articleService.save(article);
+        articleRepository.save(article);
 
         article = new Article("Second Article About Elasticsearch");
         article.setAuthors(asList(johnSmith));
         article.setTags("elasticsearch", "spring data");
-        articleService.save(article);
+        articleRepository.save(article);
 
         article = new Article("Elasticsearch Tutorial");
         article.setAuthors(asList(johnDoe));
         article.setTags("elasticsearch");
-        articleService.save(article);
+        articleRepository.save(article);
+    }
+
+    @After
+    public void after() {
+        articleRepository.deleteAll();
     }
 
     @Test
     public void givenFullTitle_whenRunMatchQuery_thenDocIsFound() {
-        final SearchQuery searchQuery = new NativeSearchQueryBuilder()
+        final NativeSearchQuery searchQuery = new NativeSearchQueryBuilder().withQuery(matchQuery("title", "Search engines").operator(Operator.AND))
-          .withQuery(matchQuery("title", "Search engines").operator(AND)).build();
+            .build();
-        final List<Article> articles = elasticsearchTemplate.queryForList(searchQuery, Article.class);
+        final SearchHits<Article> articles = elasticsearchTemplate.search(searchQuery, Article.class, IndexCoordinates.of("blog"));
-        assertEquals(1, articles.size());
+        assertEquals(1, articles.getTotalHits());
     }
 
     @Test
     public void givenOneTermFromTitle_whenRunMatchQuery_thenDocIsFound() {
-        final SearchQuery searchQuery = new NativeSearchQueryBuilder()
+        final NativeSearchQuery searchQuery = new NativeSearchQueryBuilder().withQuery(matchQuery("title", "Engines Solutions"))
-          .withQuery(matchQuery("title", "Engines Solutions")).build();
+            .build();
-        final List<Article> articles = elasticsearchTemplate.queryForList(searchQuery, Article.class);
+
-        assertEquals(1, articles.size());
+        final SearchHits<Article> articles = elasticsearchTemplate.search(searchQuery, Article.class, IndexCoordinates.of("blog"));
-        assertEquals("Search engines", articles.get(0).getTitle());
+
+        assertEquals(1, articles.getTotalHits());
+        assertEquals("Search engines", articles.getSearchHit(0)
+            .getContent()
+            .getTitle());
     }
 
     @Test
     public void givenPartTitle_whenRunMatchQuery_thenDocIsFound() {
-        final SearchQuery searchQuery = new NativeSearchQueryBuilder()
+        final NativeSearchQuery searchQuery = new NativeSearchQueryBuilder().withQuery(matchQuery("title", "elasticsearch data"))
-          .withQuery(matchQuery("title", "elasticsearch data")).build();
+            .build();
-        final List<Article> articles = elasticsearchTemplate.queryForList(searchQuery, Article.class);
+
-        assertEquals(3, articles.size());
+        final SearchHits<Article> articles = elasticsearchTemplate.search(searchQuery, Article.class, IndexCoordinates.of("blog"));
+
+        assertEquals(3, articles.getTotalHits());
     }
 
     @Test
     public void givenFullTitle_whenRunMatchQueryOnVerbatimField_thenDocIsFound() {
-        SearchQuery searchQuery = new NativeSearchQueryBuilder()
+        NativeSearchQuery searchQuery = new NativeSearchQueryBuilder().withQuery(matchQuery("title.verbatim", "Second Article About Elasticsearch"))
-          .withQuery(matchQuery("title.verbatim", "Second Article About Elasticsearch")).build();
+            .build();
-        List<Article> articles = elasticsearchTemplate.queryForList(searchQuery, Article.class);
+
-        assertEquals(1, articles.size());
+        SearchHits<Article> articles = elasticsearchTemplate.search(searchQuery, Article.class, IndexCoordinates.of("blog"));
+
+        assertEquals(1, articles.getTotalHits());
 
         searchQuery = new NativeSearchQueryBuilder().withQuery(matchQuery("title.verbatim", "Second Article About"))
-          .build();
+            .build();
-        articles = elasticsearchTemplate.queryForList(searchQuery, Article.class);
+
-        assertEquals(0, articles.size());
+        articles = elasticsearchTemplate.search(searchQuery, Article.class, IndexCoordinates.of("blog"));
+        assertEquals(0, articles.getTotalHits());
     }
 
     @Test
     public void givenNestedObject_whenQueryByAuthorsName_thenFoundArticlesByThatAuthor() {
         final QueryBuilder builder = nestedQuery("authors", boolQuery().must(termQuery("authors.name", "smith")), ScoreMode.None);
 
-        final SearchQuery searchQuery = new NativeSearchQueryBuilder().withQuery(builder).build();
+        final NativeSearchQuery searchQuery = new NativeSearchQueryBuilder().withQuery(builder)
-        final List<Article> articles = elasticsearchTemplate.queryForList(searchQuery, Article.class);
+            .build();
+        final SearchHits<Article> articles = elasticsearchTemplate.search(searchQuery, Article.class, IndexCoordinates.of("blog"));
 
-        assertEquals(2, articles.size());
+        assertEquals(2, articles.getTotalHits());
     }
 
     @Test
-    public void givenAnalyzedQuery_whenMakeAggregationOnTermCount_thenEachTokenCountsSeparately() {
+    public void givenAnalyzedQuery_whenMakeAggregationOnTermCount_thenEachTokenCountsSeparately() throws Exception {
-        final TermsAggregationBuilder aggregation = AggregationBuilders.terms("top_tags").field("title");
+        final TermsAggregationBuilder aggregation = AggregationBuilders.terms("top_tags")
-        final SearchResponse response = client.prepareSearch("blog").setTypes("article").addAggregation(aggregation)
+            .field("title");
-          .execute().actionGet();
 
-        final Map<String, Aggregation> results = response.getAggregations().asMap();
+        final SearchSourceBuilder builder = new SearchSourceBuilder().aggregation(aggregation);
-        final StringTerms topTags = (StringTerms) results.get("top_tags");
+        final SearchRequest searchRequest = new SearchRequest("blog").source(builder);
 
-        final List<String> keys = topTags.getBuckets().stream()
+        final SearchResponse response = client.search(searchRequest, RequestOptions.DEFAULT);
-          .map(MultiBucketsAggregation.Bucket::getKeyAsString)
+
-          .sorted()
+        final Map<String, Aggregation> results = response.getAggregations()
-          .collect(toList());
+            .asMap();
+        final ParsedStringTerms topTags = (ParsedStringTerms) results.get("top_tags");
+
+        final List<String> keys = topTags.getBuckets()
+            .stream()
+            .map(MultiBucketsAggregation.Bucket::getKeyAsString)
+            .sorted()
+            .collect(toList());
         assertEquals(asList("about", "article", "data", "elasticsearch", "engines", "search", "second", "spring", "tutorial"), keys);
     }
 
     @Test
-    public void givenNotAnalyzedQuery_whenMakeAggregationOnTermCount_thenEachTermCountsIndividually() {
+    public void givenNotAnalyzedQuery_whenMakeAggregationOnTermCount_thenEachTermCountsIndividually() throws Exception {
-        final TermsAggregationBuilder aggregation = AggregationBuilders.terms("top_tags").field("tags")
+        final TermsAggregationBuilder aggregation = AggregationBuilders.terms("top_tags")
-          .order(Terms.Order.count(false));
+            .field("tags")
-        final SearchResponse response = client.prepareSearch("blog").setTypes("article").addAggregation(aggregation)
+            .order(BucketOrder.count(false));
-          .execute().actionGet();
 
-        final Map<String, Aggregation> results = response.getAggregations().asMap();
+        final SearchSourceBuilder builder = new SearchSourceBuilder().aggregation(aggregation);
-        final StringTerms topTags = (StringTerms) results.get("top_tags");
+        final SearchRequest searchRequest = new SearchRequest().indices("blog")
+            .source(builder);
 
-        final List<String> keys = topTags.getBuckets().stream()
+        final SearchResponse response = client.search(searchRequest, RequestOptions.DEFAULT);
-          .map(MultiBucketsAggregation.Bucket::getKeyAsString)
+
-          .collect(toList());
+        final Map<String, Aggregation> results = response.getAggregations()
+            .asMap();
+        final ParsedStringTerms topTags = (ParsedStringTerms) results.get("top_tags");
+
+        final List<String> keys = topTags.getBuckets()
+            .stream()
+            .map(MultiBucketsAggregation.Bucket::getKeyAsString)
+            .collect(toList());
         assertEquals(asList("elasticsearch", "spring data", "search engines", "tutorial"), keys);
     }
 
     @Test
     public void givenNotExactPhrase_whenUseSlop_thenQueryMatches() {
-        final SearchQuery searchQuery = new NativeSearchQueryBuilder()
+        final NativeSearchQuery searchQuery = new NativeSearchQueryBuilder().withQuery(matchPhraseQuery("title", "spring elasticsearch").slop(1))
-          .withQuery(matchPhraseQuery("title", "spring elasticsearch").slop(1)).build();
+            .build();
-        final List<Article> articles = elasticsearchTemplate.queryForList(searchQuery, Article.class);
+
-        assertEquals(1, articles.size());
+        final SearchHits<Article> articles = elasticsearchTemplate.search(searchQuery, Article.class, IndexCoordinates.of("blog"));
+
+        assertEquals(1, articles.getTotalHits());
     }
 
     @Test
     public void givenPhraseWithType_whenUseFuzziness_thenQueryMatches() {
-        final SearchQuery searchQuery = new NativeSearchQueryBuilder()
+        final NativeSearchQuery searchQuery = new NativeSearchQueryBuilder().withQuery(matchQuery("title", "spring date elasticserch").operator(Operator.AND)
-          .withQuery(matchQuery("title", "spring date elasticserch").operator(AND).fuzziness(Fuzziness.ONE)
+            .fuzziness(Fuzziness.ONE)
-            .prefixLength(3)).build();
+            .prefixLength(3))
+            .build();
 
-        final List<Article> articles = elasticsearchTemplate.queryForList(searchQuery, Article.class);
+        final SearchHits<Article> articles = elasticsearchTemplate.search(searchQuery, Article.class, IndexCoordinates.of("blog"));
-        assertEquals(1, articles.size());
+
+        assertEquals(1, articles.getTotalHits());
     }
 
     @Test
     public void givenMultimatchQuery_whenDoSearch_thenAllProvidedFieldsMatch() {
-        final SearchQuery searchQuery = new NativeSearchQueryBuilder()
+        final NativeSearchQuery searchQuery = new NativeSearchQueryBuilder().withQuery(multiMatchQuery("tutorial").field("title")
-          .withQuery(multiMatchQuery("tutorial").field("title").field("tags")
+            .field("tags")
-            .type(MultiMatchQueryBuilder.Type.BEST_FIELDS)).build();
+            .type(MultiMatchQueryBuilder.Type.BEST_FIELDS))
+            .build();
 
-        final List<Article> articles = elasticsearchTemplate.queryForList(searchQuery, Article.class);
+        final SearchHits<Article> articles = elasticsearchTemplate.search(searchQuery, Article.class, IndexCoordinates.of("blog"));
-        assertEquals(2, articles.size());
+
+        assertEquals(2, articles.getTotalHits());
     }
 
     @Test
@@ -205,10 +239,10 @@ public class ElasticSearchQueryManualTest {
         final QueryBuilder builder = boolQuery().must(nestedQuery("authors", boolQuery().must(termQuery("authors.name", "doe")), ScoreMode.None))
             .filter(termQuery("tags", "elasticsearch"));
 
-        final SearchQuery searchQuery = new NativeSearchQueryBuilder().withQuery(builder)
+        final NativeSearchQuery searchQuery = new NativeSearchQueryBuilder().withQuery(builder)
             .build();
-        final List<Article> articles = elasticsearchTemplate.queryForList(searchQuery, Article.class);
+        final SearchHits<Article> articles = elasticsearchTemplate.search(searchQuery, Article.class, IndexCoordinates.of("blog"));
 
-        assertEquals(2, articles.size());
+        assertEquals(2, articles.getTotalHits());
     }
 }

persistence-modules/spring-data-jpa-5/pom.xml

@@ -1,6 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+
     <modelVersion>4.0.0</modelVersion>
     <artifactId>spring-data-jpa-5</artifactId>
     <name>spring-data-jpa-5</name>
@@ -11,7 +12,7 @@
         <version>0.0.1-SNAPSHOT</version>
         <relativePath>../../parent-boot-2</relativePath>
     </parent>
-
+    
     <dependencies>
         <dependency>
             <groupId>org.springframework.boot</groupId>
@@ -28,10 +29,43 @@
             <artifactId>spring-boot-starter-data-jdbc</artifactId>
         </dependency>
 
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-cache</artifactId>
+        </dependency>
+      
         <dependency>
             <groupId>com.h2database</groupId>
             <artifactId>h2</artifactId>
         </dependency>
+      
+        <dependency>
+            <groupId>org.mapstruct</groupId>
+            <artifactId>mapstruct-jdk8</artifactId>
+            <version>1.3.1.Final</version>
+            <scope>provided</scope>
+        </dependency>
+      
     </dependencies>
-</project>
 
+    <build>
+        <sourceDirectory>src/main/java</sourceDirectory>
+        <plugins>
+            <plugin>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <version>3.8.1</version>
+                <configuration>
+                    <source>1.8</source>
+                    <target>1.8</target>
+                    <annotationProcessorPaths>
+                        <path>
+                            <groupId>org.mapstruct</groupId>
+                            <artifactId>mapstruct-processor</artifactId>
+                            <version>1.3.1.Final</version>
+                        </path>
+                    </annotationProcessorPaths>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+</project>

persistence-modules/spring-data-jpa-5/src/main/java/com/baeldung/partialupdate/PartialUpdateApplication.java

@@ -0,0 +1,12 @@
+package com.baeldung.partialupdate;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication 
+public class PartialUpdateApplication {
+
+    public static void main(String[] args) {
+        SpringApplication.run(PartialUpdateApplication.class, args);
+    }
+}

persistence-modules/spring-data-jpa-5/src/main/java/com/baeldung/partialupdate/model/ContactPhone.java

@@ -0,0 +1,22 @@
+package com.baeldung.partialupdate.model;
+
+import javax.persistence.Column;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+
+@Entity
+public class ContactPhone {
+    @Id 
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    public long id;
+    @Column(nullable=false)
+    public long customerId;
+    public String phone;
+
+    @Override
+    public String toString() {
+       return phone;
+    }
+}

persistence-modules/spring-data-jpa-5/src/main/java/com/baeldung/partialupdate/model/Customer.java

@@ -0,0 +1,23 @@
+package com.baeldung.partialupdate.model;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+
+@Entity
+public class Customer {
+
+    @Id 
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    public long id;
+    public String name;
+    public String phone;
+    //...
+    public String phone99;
+    
+    @Override public String toString() {
+        return String.format("Customer %s, Phone: %s", 
+                this.name, this.phone);
+    }
+}

persistence-modules/spring-data-jpa-5/src/main/java/com/baeldung/partialupdate/model/CustomerDto.java

@@ -0,0 +1,31 @@
+package com.baeldung.partialupdate.model;
+
+public class CustomerDto {
+    private long id;
+    public String name;
+    public String phone;
+    //...
+    private String phone99;
+
+    public CustomerDto(long id) {
+        this.id = id;
+    }
+
+    public CustomerDto(Customer c) {
+        this.id = c.id;
+        this.name = c.name;
+        this.phone = c.phone;
+    }
+
+    public long getId() {
+        return this.id;
+    }
+
+    public Customer convertToEntity() {
+        Customer c = new Customer();
+        c.id = id;
+        c.name = name;
+        c.phone = phone;
+        return c;
+    }
+}

persistence-modules/spring-data-jpa-5/src/main/java/com/baeldung/partialupdate/model/CustomerStructured.java

@@ -0,0 +1,27 @@
+package com.baeldung.partialupdate.model;
+
+import java.util.List;
+
+import javax.persistence.Entity;
+import javax.persistence.FetchType;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.OneToMany;
+
+@Entity
+public class CustomerStructured {
+
+    @Id 
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    public long id;
+    public String name;
+    @OneToMany(fetch = FetchType.EAGER, targetEntity = ContactPhone.class, mappedBy = "customerId") 
+    public List<ContactPhone> contactPhones;
+
+    @Override public String toString() {
+        return String.format("Customer %s, Phone: %s", 
+          this.name, this.contactPhones.stream()
+          .map(e -> e.toString()).reduce("", String::concat));
+    }
+}

persistence-modules/spring-data-jpa-5/src/main/java/com/baeldung/partialupdate/repository/ContactPhoneRepository.java

@@ -0,0 +1,12 @@
+package com.baeldung.partialupdate.repository;
+
+import org.springframework.data.repository.CrudRepository;
+import org.springframework.stereotype.Repository;
+
+import com.baeldung.partialupdate.model.ContactPhone;
+
+@Repository
+public interface ContactPhoneRepository extends CrudRepository<ContactPhone, Long> {
+    ContactPhone findById(long id);
+    ContactPhone findByCustomerId(long id);
+}

persistence-modules/spring-data-jpa-5/src/main/java/com/baeldung/partialupdate/repository/CustomerRepository.java

@@ -0,0 +1,18 @@
+package com.baeldung.partialupdate.repository;
+
+import org.springframework.data.jpa.repository.Modifying;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.CrudRepository;
+import org.springframework.data.repository.query.Param;
+import org.springframework.stereotype.Repository;
+
+import com.baeldung.partialupdate.model.Customer;
+
+@Repository
+public interface CustomerRepository extends CrudRepository<Customer, Long> {
+    Customer findById(long id);
+
+    @Modifying
+    @Query("update Customer u set u.phone = :phone where u.id = :id")
+    void updatePhone(@Param(value = "id") long id, @Param(value = "phone") String phone);
+}

persistence-modules/spring-data-jpa-5/src/main/java/com/baeldung/partialupdate/repository/CustomerStructuredRepository.java

@@ -0,0 +1,11 @@
+package com.baeldung.partialupdate.repository;
+
+import org.springframework.data.repository.CrudRepository;
+import org.springframework.stereotype.Repository;
+
+import com.baeldung.partialupdate.model.CustomerStructured;
+
+@Repository
+public interface CustomerStructuredRepository extends CrudRepository<CustomerStructured, Long> {
+    CustomerStructured findById(long id);
+}

persistence-modules/spring-data-jpa-5/src/main/java/com/baeldung/partialupdate/service/CustomerService.java

@@ -0,0 +1,87 @@
+package com.baeldung.partialupdate.service;
+
+import javax.transaction.Transactional;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+
+import com.baeldung.partialupdate.model.ContactPhone;
+import com.baeldung.partialupdate.model.Customer;
+import com.baeldung.partialupdate.model.CustomerDto;
+import com.baeldung.partialupdate.model.CustomerStructured;
+import com.baeldung.partialupdate.repository.ContactPhoneRepository;
+import com.baeldung.partialupdate.repository.CustomerRepository;
+import com.baeldung.partialupdate.repository.CustomerStructuredRepository;
+import com.baeldung.partialupdate.util.CustomerMapper;
+
+@Service 
+@Transactional
+public class CustomerService {
+
+    @Autowired 
+    CustomerRepository repo;
+    @Autowired 
+    CustomerStructuredRepository repo2;
+    @Autowired 
+    ContactPhoneRepository repo3;
+    @Autowired 
+    CustomerMapper mapper;
+
+    public Customer getCustomer(long id) {
+        return repo.findById(id);
+    }
+
+    public void updateCustomerWithCustomQuery(long id, String phone) {
+        repo.updatePhone(id, phone);
+    }
+
+    public Customer addCustomer(String name) {
+        Customer myCustomer = new Customer();
+        myCustomer.name = name;
+        repo.save(myCustomer);
+        return myCustomer;
+    }
+
+    public Customer updateCustomer(long id, String phone) {
+        Customer myCustomer = repo.findById(id);
+        myCustomer.phone = phone;
+        repo.save(myCustomer);
+        return myCustomer;
+    }
+
+    public Customer addCustomer(CustomerDto dto) {
+        Customer myCustomer = new Customer();
+        mapper.updateCustomerFromDto(dto, myCustomer);
+        repo.save(myCustomer);
+        return myCustomer;
+    }
+
+    public Customer updateCustomer(CustomerDto dto) {
+        Customer myCustomer = repo.findById(dto.getId());
+        mapper.updateCustomerFromDto(dto, myCustomer);
+        repo.save(myCustomer);
+        return myCustomer;
+    }
+
+    public CustomerStructured addCustomerStructured(String name) {
+        CustomerStructured myCustomer = new CustomerStructured();
+        myCustomer.name = name;
+        repo2.save(myCustomer);
+        return myCustomer;
+    }
+
+    public void addCustomerPhone(long customerId, String phone) {
+        ContactPhone myPhone = new ContactPhone();
+        myPhone.phone = phone;
+        myPhone.customerId =  customerId;
+        repo3.save(myPhone);
+    }
+    
+    public CustomerStructured updateCustomerStructured(long id, String name) {
+        CustomerStructured myCustomer = repo2.findById(id);
+        myCustomer.name = name;
+        repo2.save(myCustomer);
+        return myCustomer;
+    }
+
+}

persistence-modules/spring-data-jpa-5/src/main/java/com/baeldung/partialupdate/util/CustomerMapper.java

@@ -0,0 +1,15 @@
+package com.baeldung.partialupdate.util;
+
+import org.mapstruct.BeanMapping;
+import org.mapstruct.Mapper;
+import org.mapstruct.MappingTarget;
+import org.mapstruct.NullValuePropertyMappingStrategy;
+
+import com.baeldung.partialupdate.model.Customer;
+import com.baeldung.partialupdate.model.CustomerDto;
+
+@Mapper(componentModel = "spring")
+public interface CustomerMapper {
+    @BeanMapping(nullValuePropertyMappingStrategy = NullValuePropertyMappingStrategy.IGNORE)
+    void updateCustomerFromDto(CustomerDto dto, @MappingTarget Customer entity);
+}

persistence-modules/spring-data-jpa-5/src/test/java/com/baeldung/partialupdate/PartialUpdateUnitTest.java

@@ -0,0 +1,63 @@
+package com.baeldung.partialupdate;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotEquals;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit4.SpringRunner;
+
+import com.baeldung.partialupdate.model.Customer;
+import com.baeldung.partialupdate.model.CustomerDto;
+import com.baeldung.partialupdate.model.CustomerStructured;
+import com.baeldung.partialupdate.service.CustomerService;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest(classes = PartialUpdateApplication.class)
+public class PartialUpdateUnitTest {
+
+    @Autowired
+    CustomerService service;
+
+	@Test
+    public void givenCustomer_whenUpdate_thenSuccess() {
+        Customer myCustomer = service.addCustomer("John");
+        myCustomer = service.updateCustomer(myCustomer.id, "+00");
+        assertEquals("+00", myCustomer.phone);
+    }
+
+    @Test
+    public void givenCustomer_whenUpdateWithQuery_thenSuccess() {
+        Customer myCustomer = service.addCustomer("John");
+        service.updateCustomerWithCustomQuery(myCustomer.id, "+88");
+        myCustomer = service.getCustomer(myCustomer.id);
+        assertEquals("+88", myCustomer.phone);
+    }
+
+    @Test
+    public void givenCustomerDto_whenUpdateWithMapper_thenSuccess() {
+        CustomerDto dto = new CustomerDto(new Customer());
+        dto.name = "Johnny";
+        Customer entity = service.addCustomer(dto);
+
+        CustomerDto dto2 = new CustomerDto(entity.id);
+        dto2.phone = "+44";
+        entity = service.updateCustomer(dto2);
+
+        assertEquals("Johnny", entity.name);
+    }
+
+    @Test
+    public void givenCustomerStructured_whenUpdateCustomerPhone_thenSuccess() {
+        CustomerStructured myCustomer = service.addCustomerStructured("John");
+        assertEquals(null, myCustomer.contactPhones);
+
+        service.addCustomerPhone(myCustomer.id, "+44");
+        myCustomer = service.updateCustomerStructured(myCustomer.id, "Mr. John");
+
+        assertNotEquals(null, myCustomer.contactPhones);
+        assertEquals(1, myCustomer.contactPhones.size());
+    }
+}

persistence-modules/spring-data-redis/README.md

@@ -4,7 +4,6 @@
 - [Introduction to Spring Data Redis](https://www.baeldung.com/spring-data-redis-tutorial)
 - [PubSub Messaging with Spring Data Redis](https://www.baeldung.com/spring-data-redis-pub-sub)
 - [An Introduction to Spring Data Redis Reactive](https://www.baeldung.com/spring-data-redis-reactive)
-- [Delete Everything in Redis](https://www.baeldung.com/redis-delete-data)
 
 ### Build the Project with Tests Running
 ```
@@ -15,4 +14,3 @@ mvn clean install
 ```
 mvn test
 ```
-

persistence-modules/spring-data-redis/src/main/java/com/baeldung/spring/data/redis/config/RedisConfig.java

@@ -35,18 +35,6 @@ public class RedisConfig {
         template.setValueSerializer(new GenericToStringSerializer<Object>(Object.class));
         return template;
     }
-    
-    @Bean
-    public LettuceConnectionFactory lettuceConnectionFactory() {
-        return new LettuceConnectionFactory();
-    }
-
-    @Bean(name = "flushRedisTemplate")
-    public RedisTemplate<String, String> flushRedisTemplate() {
-        RedisTemplate<String, String> template = new RedisTemplate<>();
-        template.setConnectionFactory(lettuceConnectionFactory());
-        return template;
-    }
 
     @Bean
     MessageListenerAdapter messageListener() {

persistence-modules/spring-data-redis/src/test/java/com/baeldung/spring/data/redis/delete/RedisFlushDatabaseIntegrationTest.java

@@ -1,92 +0,0 @@
-package com.baeldung.spring.data.redis.delete;
-
-import static org.assertj.core.api.Assertions.assertThat;
-
-import java.io.IOException;
-
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.beans.factory.annotation.Qualifier;
-import org.springframework.dao.DataAccessException;
-import org.springframework.data.redis.connection.RedisConnection;
-import org.springframework.data.redis.core.RedisCallback;
-import org.springframework.data.redis.core.RedisTemplate;
-import org.springframework.data.redis.core.ValueOperations;
-import org.springframework.test.annotation.DirtiesContext;
-import org.springframework.test.annotation.DirtiesContext.ClassMode;
-import org.springframework.test.context.ContextConfiguration;
-import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
-
-import com.baeldung.spring.data.redis.config.RedisConfig;
-
-import redis.embedded.RedisServer;
-
-@RunWith(SpringJUnit4ClassRunner.class)
-@ContextConfiguration(classes = { RedisConfig.class })
-@DirtiesContext(classMode = ClassMode.BEFORE_CLASS)
-public class RedisFlushDatabaseIntegrationTest {
-
-    private RedisServer redisServer;
-
-    @Autowired
-    @Qualifier("flushRedisTemplate")
-    private RedisTemplate<String, String> flushRedisTemplate;
-
-    @Before
-    public void setup() throws IOException {
-        redisServer = new RedisServer(6390);
-        redisServer.start();
-    }
-
-    @After
-    public void tearDown() {
-        redisServer.stop();
-    }
-
-    @Test
-    public void whenFlushDB_thenAllKeysInDatabaseAreCleared() {
-
-        ValueOperations<String, String> simpleValues = flushRedisTemplate.opsForValue();
-        String key = "key";
-        String value = "value";
-        simpleValues.set(key, value);
-        assertThat(simpleValues.get(key)).isEqualTo(value);
-
-        flushRedisTemplate.execute(new RedisCallback<Void>() {
-
-            @Override
-            public Void doInRedis(RedisConnection connection) throws DataAccessException {
-                connection.flushDb();
-                return null;
-            }
-        });
-
-        assertThat(simpleValues.get(key)).isNull();
-
-    }
-    
-    @Test
-    public void whenFlushAll_thenAllKeysInDatabasesAreCleared() {
-
-        ValueOperations<String, String> simpleValues = flushRedisTemplate.opsForValue();
-        String key = "key";
-        String value = "value";
-        simpleValues.set(key, value);
-        assertThat(simpleValues.get(key)).isEqualTo(value);
-
-        flushRedisTemplate.execute(new RedisCallback<Void>() {
-
-            @Override
-            public Void doInRedis(RedisConnection connection) throws DataAccessException {
-                connection.flushAll();
-                return null;
-            }
-        });
-
-        assertThat(simpleValues.get(key)).isNull();
-
-    }
-}

pom.xml

@@ -513,6 +513,7 @@
                 <module>libraries-rpc</module>
                 <module>libraries-security</module>
                 <module>libraries-server</module>
+                <module>libraries-server-2</module>
                 <module>libraries-testing</module>
                 <module>linkrest</module>
                 <module>logging-modules</module>
@@ -1032,6 +1033,7 @@
                 <module>libraries-primitive</module>
                 <module>libraries-security</module>
                 <module>libraries-server</module>
+                <module>libraries-server-2</module>
                 <module>libraries-testing</module>
                 <module>linkrest</module>
                 <module>logging-modules</module>

spring-boot-modules/spring-boot-libraries/pom.xml

@@ -87,7 +87,35 @@
             <artifactId>javase</artifactId>
             <version>${zxing.version}</version>
         </dependency>
-
+        <!-- Bucket4j -->
+        <dependency>
+            <groupId>com.github.vladimir-bukhtoyarov</groupId>
+            <artifactId>bucket4j-core</artifactId>
+            <version>${bucket4j.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.giffing.bucket4j.spring.boot.starter</groupId>
+            <artifactId>bucket4j-spring-boot-starter</artifactId>
+            <version>${bucket4j-spring-boot-starter.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-cache</artifactId>
+            </dependency>
+        <dependency>
+            <groupId>javax.cache</groupId>
+            <artifactId>cache-api</artifactId>
+            </dependency>
+        <dependency>
+            <groupId>com.github.ben-manes.caffeine</groupId>
+            <artifactId>caffeine</artifactId>
+            <version>${caffeine.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.github.ben-manes.caffeine</groupId>
+            <artifactId>jcache</artifactId>
+            <version>${caffeine.version}</version>
+        </dependency>
     </dependencies>
 
     <repositories>
@@ -200,6 +228,9 @@
         <barcode4j.version>2.1</barcode4j.version>
         <qrgen.version>2.6.0</qrgen.version>
         <zxing.version>3.3.0</zxing.version>
+        <bucket4j.version>4.10.0</bucket4j.version>
+        <bucket4j-spring-boot-starter.version>0.2.0</bucket4j-spring-boot-starter.version>
+        <caffeine.version>2.8.2</caffeine.version>
     </properties>
 
 </project>

spring-boot-modules/spring-boot-libraries/src/main/java/com/baeldung/ratelimiting/bootstarterapp/Bucket4jRateLimitApp.java

@@ -0,0 +1,21 @@
+package com.baeldung.ratelimiting.bootstarterapp;
+
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
+import org.springframework.boot.autoconfigure.security.servlet.SecurityAutoConfiguration;
+import org.springframework.boot.builder.SpringApplicationBuilder;
+import org.springframework.cache.annotation.EnableCaching;
+
+@SpringBootApplication(scanBasePackages = "com.baeldung.ratelimiting", exclude = {
+    DataSourceAutoConfiguration.class,
+    SecurityAutoConfiguration.class,
+})
+@EnableCaching
+public class Bucket4jRateLimitApp {
+
+  public static void main(String[] args) {
+    new SpringApplicationBuilder(Bucket4jRateLimitApp.class)
+        .properties("spring.config.location=classpath:ratelimiting/application-bucket4j-starter.yml")
+        .run(args);
+  }
+}

spring-boot-modules/spring-boot-libraries/src/main/java/com/baeldung/ratelimiting/bucket4japp/Bucket4jRateLimitApp.java

@@ -0,0 +1,35 @@
+package com.baeldung.ratelimiting.bucket4japp;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
+import org.springframework.boot.autoconfigure.security.servlet.SecurityAutoConfiguration;
+import org.springframework.boot.builder.SpringApplicationBuilder;
+import org.springframework.context.annotation.Lazy;
+import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
+import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
+
+import com.baeldung.ratelimiting.bucket4japp.interceptor.RateLimitInterceptor;
+
+@SpringBootApplication(scanBasePackages = "com.baeldung.ratelimiting", exclude = { 
+        DataSourceAutoConfiguration.class,
+        SecurityAutoConfiguration.class
+})
+public class Bucket4jRateLimitApp implements WebMvcConfigurer {
+    
+    @Autowired
+    @Lazy
+    private RateLimitInterceptor interceptor;
+
+    @Override
+    public void addInterceptors(InterceptorRegistry registry) {
+        registry.addInterceptor(interceptor)
+            .addPathPatterns("/api/v1/area/**");
+    }
+
+    public static void main(String[] args) {
+        new SpringApplicationBuilder(Bucket4jRateLimitApp.class)
+            .properties("spring.config.location=classpath:ratelimiting/application-bucket4j.yml")
+            .run(args);
+    }
+}

spring-boot-modules/spring-boot-libraries/src/main/java/com/baeldung/ratelimiting/bucket4japp/interceptor/RateLimitInterceptor.java

@@ -0,0 +1,57 @@
+package com.baeldung.ratelimiting.bucket4japp.interceptor;
+
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.stereotype.Component;
+import org.springframework.web.servlet.HandlerInterceptor;
+
+import com.baeldung.ratelimiting.bucket4japp.service.PricingPlanService;
+
+import io.github.bucket4j.Bucket;
+import io.github.bucket4j.ConsumptionProbe;
+
+@Component
+public class RateLimitInterceptor implements HandlerInterceptor {
+
+    private static final String HEADER_API_KEY = "X-api-key";
+    private static final String HEADER_LIMIT_REMAINING = "X-Rate-Limit-Remaining";
+    private static final String HEADER_RETRY_AFTER = "X-Rate-Limit-Retry-After-Seconds";
+
+    @Autowired
+    private PricingPlanService pricingPlanService;
+
+    @Override
+    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
+
+        String apiKey = request.getHeader(HEADER_API_KEY);
+
+        if (apiKey == null || apiKey.isEmpty()) {
+            response.sendError(HttpStatus.BAD_REQUEST.value(), "Missing Header: " + HEADER_API_KEY);
+            return false;
+        }
+
+        Bucket tokenBucket = pricingPlanService.resolveBucket(apiKey);
+
+        ConsumptionProbe probe = tokenBucket.tryConsumeAndReturnRemaining(1);
+
+        if (probe.isConsumed()) {
+
+            response.addHeader(HEADER_LIMIT_REMAINING, String.valueOf(probe.getRemainingTokens()));
+            return true;
+
+        } else {
+
+            long waitForRefill = probe.getNanosToWaitForRefill() / 1_000_000_000;
+
+            response.setContentType(MediaType.APPLICATION_JSON_VALUE);
+            response.addHeader(HEADER_RETRY_AFTER, String.valueOf(waitForRefill));
+            response.sendError(HttpStatus.TOO_MANY_REQUESTS.value(), "You have exhausted your API Request Quota"); // 429
+
+            return false;
+        }
+    }
+}

spring-boot-modules/spring-boot-libraries/src/main/java/com/baeldung/ratelimiting/bucket4japp/service/PricingPlan.java

@@ -0,0 +1,42 @@
+package com.baeldung.ratelimiting.bucket4japp.service;
+
+import java.time.Duration;
+
+import io.github.bucket4j.Bandwidth;
+import io.github.bucket4j.Refill;
+
+public enum PricingPlan {
+
+    FREE(20),
+
+    BASIC(40),
+
+    PROFESSIONAL(100);
+
+    private int bucketCapacity;
+    
+    private PricingPlan(int bucketCapacity) {
+        this.bucketCapacity = bucketCapacity;
+    }
+    
+    Bandwidth getLimit() {
+        return Bandwidth.classic(bucketCapacity, Refill.intervally(bucketCapacity, Duration.ofHours(1)));
+    }
+    
+    public int bucketCapacity() {
+        return bucketCapacity;
+    }
+    
+    static PricingPlan resolvePlanFromApiKey(String apiKey) {
+        if (apiKey == null || apiKey.isEmpty()) {
+            return FREE;
+        
+        } else if (apiKey.startsWith("PX001-")) {
+            return PROFESSIONAL;
+            
+        } else if (apiKey.startsWith("BX001-")) {
+            return BASIC;
+        }
+        return FREE;
+    }
+}

spring-boot-modules/spring-boot-libraries/src/main/java/com/baeldung/ratelimiting/bucket4japp/service/PricingPlanService.java

@@ -0,0 +1,31 @@
+package com.baeldung.ratelimiting.bucket4japp.service;
+
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+
+import org.springframework.stereotype.Service;
+
+import io.github.bucket4j.Bandwidth;
+import io.github.bucket4j.Bucket;
+import io.github.bucket4j.Bucket4j;
+
+@Service
+public class PricingPlanService {
+
+    private final Map<String, Bucket> cache = new ConcurrentHashMap<>();
+
+    public Bucket resolveBucket(String apiKey) {
+        return cache.computeIfAbsent(apiKey, this::newBucket);
+    }
+
+    private Bucket newBucket(String apiKey) {
+        PricingPlan pricingPlan = PricingPlan.resolvePlanFromApiKey(apiKey);
+        return bucket(pricingPlan.getLimit());
+    }
+
+    private Bucket bucket(Bandwidth limit) {
+        return Bucket4j.builder()
+            .addLimit(limit)
+            .build();
+    }
+}

spring-boot-modules/spring-boot-libraries/src/main/java/com/baeldung/ratelimiting/controller/AreaCalculationController.java

@@ -0,0 +1,29 @@
+package com.baeldung.ratelimiting.controller;
+
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import com.baeldung.ratelimiting.dto.AreaV1;
+import com.baeldung.ratelimiting.dto.RectangleDimensionsV1;
+import com.baeldung.ratelimiting.dto.TriangleDimensionsV1;
+
+@RestController
+@RequestMapping(value = "/api/v1/area", consumes = MediaType.APPLICATION_JSON_VALUE)
+class AreaCalculationController {
+
+    @PostMapping(value = "/rectangle", produces = MediaType.APPLICATION_JSON_VALUE)
+    public ResponseEntity<AreaV1> rectangle(@RequestBody RectangleDimensionsV1 dimensions) {
+
+        return ResponseEntity.ok(new AreaV1("rectangle", dimensions.getLength() * dimensions.getWidth()));
+    }
+
+    @PostMapping(value = "/triangle", produces = MediaType.APPLICATION_JSON_VALUE)
+    public ResponseEntity<AreaV1> triangle(@RequestBody TriangleDimensionsV1 dimensions) {
+
+        return ResponseEntity.ok(new AreaV1("triangle", 0.5d * dimensions.getHeight() * dimensions.getBase()));
+    }
+}

spring-boot-modules/spring-boot-libraries/src/main/java/com/baeldung/ratelimiting/dto/AreaV1.java

@@ -0,0 +1,20 @@
+package com.baeldung.ratelimiting.dto;
+
+public class AreaV1 {
+
+    private String shape;
+    private Double area;
+    
+    public AreaV1(String shape, Double area) {
+        this.area = area;
+        this.shape = shape;
+    }
+    
+    public Double getArea() {
+        return area;
+    }
+    
+    public String getShape() {
+        return shape;
+    }
+}

spring-boot-modules/spring-boot-libraries/src/main/java/com/baeldung/ratelimiting/dto/RectangleDimensionsV1.java

@@ -0,0 +1,15 @@
+package com.baeldung.ratelimiting.dto;
+
+public class RectangleDimensionsV1 {
+
+  private double length;
+  private double width;
+
+  public double getLength() {
+    return length;
+  }
+
+  public double getWidth() {
+    return width;
+  }
+}

spring-boot-modules/spring-boot-libraries/src/main/java/com/baeldung/ratelimiting/dto/TriangleDimensionsV1.java

@@ -0,0 +1,15 @@
+package com.baeldung.ratelimiting.dto;
+
+public class TriangleDimensionsV1 {
+
+    private double base;
+    private double height;
+
+    public double getBase() {
+      return base;
+    }
+
+    public double getHeight() {
+      return height;
+    }
+}

spring-boot-modules/spring-boot-libraries/src/main/resources/ratelimiting/application-bucket4j-starter.yml

@@ -0,0 +1,40 @@
+server:
+  port: 9001
+
+spring:
+  application:
+    name: bucket4j-starter-api-rate-limit-app
+  mvc:
+    throw-exception-if-no-handler-found: true
+  resources:
+    add-mappings: false
+  cache:
+    cache-names:
+    - rate-limit-buckets
+    caffeine:
+      spec: maximumSize=100000,expireAfterAccess=3600s
+
+bucket4j:
+  enabled: true
+  filters:
+  - cache-name: rate-limit-buckets
+    url: /api/v1/area.*
+    http-response-body: "{ \"status\": 429, \"error\": \"Too Many Requests\", \"message\": \"You have exhausted your API Request Quota\" }"
+    rate-limits:
+    - expression: "getHeader('X-api-key')"
+      execute-condition: "getHeader('X-api-key').startsWith('PX001-')"
+      bandwidths:
+      - capacity: 100
+        time: 1
+        unit: hours
+    - expression: "getHeader('X-api-key')"
+      execute-condition: "getHeader('X-api-key').startsWith('BX001-')"
+      bandwidths:
+      - capacity: 40
+        time: 1
+        unit: hours
+    - expression: "getHeader('X-api-key')"
+      bandwidths:
+      - capacity: 20
+        time: 1
+        unit: hours

spring-boot-modules/spring-boot-libraries/src/main/resources/ratelimiting/application-bucket4j.yml

@@ -0,0 +1,10 @@
+server:
+  port: 9000
+
+spring:
+  application:
+    name: bucket4j-api-rate-limit-app
+  mvc:
+    throw-exception-if-no-handler-found: true
+  resources:
+    add-mappings: false

spring-boot-modules/spring-boot-libraries/src/test/java/com/baeldung/ratelimiting/bootstarterapp/Bucket4jBootStarterRateLimitIntegrationTest.java

@@ -0,0 +1,63 @@
+package com.baeldung.ratelimiting.bootstarterapp;
+
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.header;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.http.MediaType;
+import org.springframework.test.context.TestPropertySource;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.test.web.servlet.RequestBuilder;
+
+import com.baeldung.ratelimiting.bucket4japp.service.PricingPlan;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest(classes = Bucket4jRateLimitApp.class)
+@TestPropertySource(properties = "spring.config.location=classpath:ratelimiting/application-bucket4j-starter.yml")
+@AutoConfigureMockMvc
+public class Bucket4jBootStarterRateLimitIntegrationTest {
+
+    @Autowired
+    private MockMvc mockMvc;
+
+    @Test
+    public void givenTriangleAreaCalculator_whenRequestsWithinRateLimit_thenAccepted() throws Exception {
+
+        RequestBuilder request = post("/api/v1/area/triangle").contentType(MediaType.APPLICATION_JSON_VALUE)
+            .content("{ \"height\": 8, \"base\": 10 }")
+            .header("X-api-key", "FX001-UBSZ5YRYQ");
+
+        for (int i = 1; i <= PricingPlan.FREE.bucketCapacity(); i++) {
+            mockMvc.perform(request)
+                .andExpect(status().isOk())
+                .andExpect(header().exists("X-Rate-Limit-Remaining"))
+                .andExpect(jsonPath("$.shape", equalTo("triangle")))
+                .andExpect(jsonPath("$.area", equalTo(40d)));
+        }
+    }
+
+    @Test
+    public void givenTriangleAreaCalculator_whenRequestRateLimitTriggered_thenRejected() throws Exception {
+
+        RequestBuilder request = post("/api/v1/area/triangle").contentType(MediaType.APPLICATION_JSON_VALUE)
+            .content("{ \"height\": 8, \"base\": 10 }")
+            .header("X-api-key", "FX001-ZBSY6YSLP");
+
+        for (int i = 1; i <= PricingPlan.FREE.bucketCapacity(); i++) {
+            mockMvc.perform(request); // exhaust limit
+        }
+
+        mockMvc.perform(request)
+            .andExpect(status().isTooManyRequests())
+            .andExpect(jsonPath("$.message", equalTo("You have exhausted your API Request Quota")))
+            .andExpect(header().exists("X-Rate-Limit-Retry-After-Seconds"));
+    }
+}