Merge branch 'master' of https://github.com/eugenp/tutorials into BAEL-15958

algorithms-sorting/src/main/java/com/baeldung/algorithms/inoutsort/InOutSort.java

@@ -0,0 +1,25 @@
+package com.baeldung.algorithms.inoutsort;
+
+public class InOutSort {
+
+    public static int[] reverseInPlace(int A[]) {
+        int n = A.length;
+        for (int i = 0; i < n / 2; i++) {
+            int temp = A[i];
+            A[i] = A[n - 1 - i];
+            A[n - 1 - i] = temp;
+        }
+
+        return A;
+    }
+
+    public static int[] reverseOutOfPlace(int A[]) {
+        int n = A.length;
+        int[] B = new int[n];
+        for (int i = 0; i < n; i++) {
+            B[n - i - 1] = A[i];
+        }
+
+        return B;
+    }
+}

algorithms-sorting/src/test/java/com/baeldung/algorithms/inoutsort/InOutSortUnitTest.java

@@ -0,0 +1,23 @@
+package com.baeldung.algorithms.inoutsort;
+
+import static org.junit.Assert.*;
+import static org.junit.Assert.assertArrayEquals;
+
+import org.junit.Test;
+
+public class InOutSortUnitTest {
+
+    @Test
+    public void givenArray_whenInPlaceSort_thenReversed() {
+        int[] input = {1, 2, 3, 4, 5, 6, 7};
+        int[] expected = {7, 6, 5, 4, 3, 2, 1};
+        assertArrayEquals("the two arrays are not equal", expected, InOutSort.reverseInPlace(input));
+    }
+
+    @Test
+    public void givenArray_whenOutOfPlaceSort_thenReversed() {
+        int[] input = {1, 2, 3, 4, 5, 6, 7};
+        int[] expected = {7, 6, 5, 4, 3, 2, 1};
+        assertArrayEquals("the two arrays are not equal", expected, InOutSort.reverseOutOfPlace(input));
+    }
+}

core-java-modules/core-java-lang-operators/src/test/java/com/baeldung/unaryoperators/IncrementDecrementUnaryOperatorUnitTest.java

@@ -1,4 +1,4 @@
-package com.baeldung.incrementdecrementunaryoperators;
+package com.baeldung.unaryoperators;
 
 import static org.assertj.core.api.Assertions.assertThat;
 

jackson-2/src/main/java/com/baeldung/jackson/entities/File.java

@@ -0,0 +1,25 @@
+package com.baeldung.jackson.entities;
+
+public class File {
+
+    private Long id;
+
+    private String name;
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+}

jackson-2/src/main/java/com/baeldung/jackson/entities/Folder.java

@@ -0,0 +1,82 @@
+package com.baeldung.jackson.entities;
+
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.List;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+
+public class Folder {
+
+    private Long id;
+
+    private String name;
+
+    private String owner;
+
+    private Date created;
+
+    private Date modified;
+
+    private Date lastAccess;
+
+    @JsonIgnore
+    private List<File> files = new ArrayList<>();
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getOwner() {
+        return owner;
+    }
+
+    public void setOwner(String owner) {
+        this.owner = owner;
+    }
+
+    public Date getCreated() {
+        return created;
+    }
+
+    public void setCreated(Date created) {
+        this.created = created;
+    }
+
+    public Date getModified() {
+        return modified;
+    }
+
+    public void setModified(Date modified) {
+        this.modified = modified;
+    }
+
+    public Date getLastAccess() {
+        return lastAccess;
+    }
+
+    public void setLastAccess(Date lastAccess) {
+        this.lastAccess = lastAccess;
+    }
+
+    public List<File> getFiles() {
+        return files;
+    }
+
+    public void setFiles(List<File> files) {
+        this.files = files;
+    }
+
+}

jackson-2/src/main/java/com/baeldung/jackson/serialization/custom/serializer/FolderBeanSerializerModifier.java

@@ -0,0 +1,21 @@
+package com.baeldung.jackson.serialization.custom.serializer;
+
+import com.baeldung.jackson.entities.Folder;
+import com.fasterxml.jackson.databind.BeanDescription;
+import com.fasterxml.jackson.databind.JsonSerializer;
+import com.fasterxml.jackson.databind.SerializationConfig;
+import com.fasterxml.jackson.databind.ser.BeanSerializerModifier;
+
+public class FolderBeanSerializerModifier extends BeanSerializerModifier {
+
+    @Override
+    public JsonSerializer<?> modifySerializer(SerializationConfig config, BeanDescription beanDesc, JsonSerializer<?> serializer) {
+
+        if (beanDesc.getBeanClass().equals(Folder.class)) {
+            return new FolderSerializerWithDefaultSerializerStored((JsonSerializer<Object>) serializer);
+        }
+
+        return serializer;
+    }
+
+}

jackson-2/src/main/java/com/baeldung/jackson/serialization/custom/serializer/FolderSerializer.java

@@ -0,0 +1,36 @@
+package com.baeldung.jackson.serialization.custom.serializer;
+
+import java.io.IOException;
+
+import com.baeldung.jackson.entities.File;
+import com.baeldung.jackson.entities.Folder;
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.databind.SerializerProvider;
+import com.fasterxml.jackson.databind.ser.std.StdSerializer;
+
+public class FolderSerializer extends StdSerializer<Folder> {
+
+    public FolderSerializer() {
+        super(Folder.class);
+    }
+
+    @Override
+    public void serialize(Folder value, JsonGenerator gen, SerializerProvider provider) throws IOException {
+
+        gen.writeStartObject();
+        gen.writeStringField("name", value.getName());
+
+        gen.writeArrayFieldStart("files");
+        for (File file : value.getFiles()) {
+            gen.writeStartObject();
+            gen.writeNumberField("id", file.getId());
+            gen.writeStringField("name", file.getName());
+            gen.writeEndObject();
+        }
+        gen.writeEndArray();
+
+        gen.writeEndObject();
+
+    }
+
+}

jackson-2/src/main/java/com/baeldung/jackson/serialization/custom/serializer/FolderSerializerWithCallingOwnSerializer.java

@@ -0,0 +1,30 @@
+package com.baeldung.jackson.serialization.custom.serializer;
+
+import java.io.IOException;
+
+import com.baeldung.jackson.entities.Folder;
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.databind.SerializerProvider;
+import com.fasterxml.jackson.databind.ser.std.StdSerializer;
+
+public class FolderSerializerWithCallingOwnSerializer extends StdSerializer<Folder> {
+
+    public FolderSerializerWithCallingOwnSerializer() {
+        super(Folder.class);
+    }
+
+    @Override
+    public void serialize(Folder value, JsonGenerator gen, SerializerProvider provider) throws IOException {
+
+        gen.writeStartObject();
+        gen.writeStringField("name", value.getName());
+
+        provider.defaultSerializeField("files", value.getFiles(), gen);
+
+        provider.defaultSerializeField("details", value, gen);
+
+        gen.writeEndObject();
+
+    }
+
+}

jackson-2/src/main/java/com/baeldung/jackson/serialization/custom/serializer/FolderSerializerWithDefaultSerializerStored.java

@@ -0,0 +1,35 @@
+package com.baeldung.jackson.serialization.custom.serializer;
+
+import java.io.IOException;
+
+import com.baeldung.jackson.entities.Folder;
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.databind.JsonSerializer;
+import com.fasterxml.jackson.databind.SerializerProvider;
+import com.fasterxml.jackson.databind.ser.std.StdSerializer;
+
+public class FolderSerializerWithDefaultSerializerStored extends StdSerializer<Folder> {
+
+    private final JsonSerializer<Object> defaultSerializer;
+
+    public FolderSerializerWithDefaultSerializerStored(JsonSerializer<Object> defaultSerializer) {
+        super(Folder.class);
+        this.defaultSerializer = defaultSerializer;
+    }
+
+    @Override
+    public void serialize(Folder value, JsonGenerator gen, SerializerProvider provider) throws IOException {
+
+        gen.writeStartObject();
+        gen.writeStringField("name", value.getName());
+
+        provider.defaultSerializeField("files", value.getFiles(), gen);
+
+        gen.writeFieldName("details");
+        defaultSerializer.serialize(value, gen, provider);
+
+        gen.writeEndObject();
+
+    }
+
+}

jackson-2/src/main/java/com/baeldung/jackson/serialization/custom/serializer/FolderSerializerWithInternalObjectMapper.java

@@ -0,0 +1,34 @@
+package com.baeldung.jackson.serialization.custom.serializer;
+
+import java.io.IOException;
+
+import com.baeldung.jackson.entities.Folder;
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.SerializerProvider;
+import com.fasterxml.jackson.databind.ser.std.StdSerializer;
+
+public class FolderSerializerWithInternalObjectMapper extends StdSerializer<Folder> {
+
+    public FolderSerializerWithInternalObjectMapper() {
+        super(Folder.class);
+    }
+
+    @Override
+    public void serialize(Folder value, JsonGenerator gen, SerializerProvider provider) throws IOException {
+
+        gen.writeStartObject();
+        gen.writeStringField("name", value.getName());
+
+        // we access internal mapper to delegate the serialization of File list  
+        ObjectMapper mapper = (ObjectMapper) gen.getCodec();
+
+        gen.writeFieldName("files");
+        String stringValue = mapper.writeValueAsString(value.getFiles());
+        gen.writeRawValue(stringValue);
+
+        gen.writeEndObject();
+
+    }
+
+}

jackson-2/src/main/java/com/baeldung/jackson/serialization/custom/serializer/FolderSerializerWithSerializerProvider.java

@@ -0,0 +1,29 @@
+package com.baeldung.jackson.serialization.custom.serializer;
+
+import java.io.IOException;
+
+import com.baeldung.jackson.entities.Folder;
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.databind.SerializerProvider;
+import com.fasterxml.jackson.databind.ser.std.StdSerializer;
+
+public class FolderSerializerWithSerializerProvider extends StdSerializer<Folder> {
+
+    public FolderSerializerWithSerializerProvider() {
+        super(Folder.class);
+    }
+
+    @Override
+    public void serialize(Folder value, JsonGenerator gen, SerializerProvider provider) throws IOException {
+
+        gen.writeStartObject();
+        gen.writeStringField("name", value.getName());
+
+        // we delegate the File list serialization to its default serializer
+        provider.defaultSerializeField("files", value.getFiles(), gen);
+
+        gen.writeEndObject();
+
+    }
+
+}

jackson-2/src/test/java/com/baeldung/jackson/serialization/custom/serializer/CallingDefaultSerializerUnitTest.java

@@ -0,0 +1,166 @@
+package com.baeldung.jackson.serialization.custom.serializer;
+
+import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.io.IOException;
+import java.time.Instant;
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.junit.Before;
+import org.junit.Test;
+
+import com.baeldung.jackson.entities.File;
+import com.baeldung.jackson.entities.Folder;
+import com.fasterxml.jackson.core.type.TypeReference;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.module.SimpleModule;
+
+public class CallingDefaultSerializerUnitTest {
+
+    private ObjectMapper mapper;
+    private Folder mockFolder;
+    private TypeReference<HashMap<String, Object>> mapType;
+
+    @Before
+    public void setup() {
+
+        mapType = new TypeReference<HashMap<String, Object>>() {
+        };
+
+        mapper = new ObjectMapper();
+
+        mockFolder = new Folder();
+        mockFolder.setId(1L);
+        mockFolder.setName("Root Folder");
+        mockFolder.setOwner("root");
+        mockFolder.setCreated(Date.from(Instant.now().minusSeconds(60)));
+        mockFolder.setModified(Date.from(Instant.now().minusSeconds(30)));
+        mockFolder.setLastAccess(Date.from(Instant.now()));
+
+        File file1 = new File();
+        file1.setId(1L);
+        file1.setName("File 1");
+
+        File file2 = new File();
+        file2.setId(2L);
+        file2.setName("File 2");
+
+        List<File> files = new ArrayList<>();
+        files.add(file1);
+        files.add(file2);
+        mockFolder.setFiles(files);
+
+    }
+
+    @Test
+    public void givenFolder_whenSerialized_onlyNameAndFilesFieldsSerialized() throws IOException {
+
+        SimpleModule module = new SimpleModule();
+        module.addSerializer(new FolderSerializer());
+        mapper.registerModule(module);
+
+        String json = mapper.writeValueAsString(mockFolder);
+
+        HashMap<String, Object> actual = mapper.readValue(json, mapType);
+
+        assertTrue(actual.containsKey("name"));
+        assertTrue(actual.containsKey("files"));
+        assertEquals(mockFolder.getName(), actual.get("name"));
+
+        List actualFiles = (List) actual.get("files");
+        assertEquals(mockFolder.getFiles().size(), actualFiles.size());
+        
+    }
+
+    @Test
+    public void givenFolder_whenSerializedWithSerializerProvider_onlyNameAndFilesFieldsSerialized() throws IOException {
+
+        SimpleModule module = new SimpleModule();
+        module.addSerializer(new FolderSerializerWithSerializerProvider());
+        mapper.registerModule(module);
+
+        String json = mapper.writeValueAsString(mockFolder);
+
+        HashMap<String, Object> actual = mapper.readValue(json, mapType);
+
+        assertTrue(actual.containsKey("name"));
+        assertTrue(actual.containsKey("files"));
+        assertEquals(mockFolder.getName(), actual.get("name"));
+
+        List actualFiles = (List) actual.get("files");
+        assertEquals(mockFolder.getFiles().size(), actualFiles.size());
+
+    }
+
+    @Test
+    public void givenFolder_whenSerializedWithInternalObjectMapper_onlyNameAndFilesFieldsSerialized() throws IOException {
+
+        SimpleModule module = new SimpleModule();
+        module.addSerializer(new FolderSerializerWithInternalObjectMapper());
+        mapper.registerModule(module);
+
+        String json = mapper.writeValueAsString(mockFolder);
+
+        HashMap<String, Object> actual = mapper.readValue(json, mapType);
+
+        assertTrue(actual.containsKey("name"));
+        assertTrue(actual.containsKey("files"));
+        assertEquals(mockFolder.getName(), actual.get("name"));
+
+        List actualFiles = (List) actual.get("files");
+        assertEquals(mockFolder.getFiles().size(), actualFiles.size());
+
+    }
+
+    @Test(expected = StackOverflowError.class)
+    public void givenFolder_whenSerializedWithCallingOwnSerializer_exceptionOccured() throws IOException {
+
+        SimpleModule module = new SimpleModule();
+        module.addSerializer(new FolderSerializerWithCallingOwnSerializer());
+        mapper.registerModule(module);
+
+        mapper.writeValueAsString(mockFolder);
+        
+    }
+
+    @Test
+    public void givenFolder_whenSerializedWithDefaultSerializerStored_NameAndFilesAndDetailsFieldsSerialized() throws IOException {
+
+        SimpleModule module = new SimpleModule();
+        module.setSerializerModifier(new FolderBeanSerializerModifier());
+        mapper.registerModule(module);
+
+        String json = mapper.writeValueAsString(mockFolder);
+        
+        HashMap<String, Object> actual = mapper.readValue(json, mapType);
+
+        assertTrue(actual.containsKey("name"));
+        assertTrue(actual.containsKey("files"));
+        assertEquals(mockFolder.getName(), actual.get("name"));
+
+        List actualFiles = (List) actual.get("files");
+        assertEquals(mockFolder.getFiles().size(), actualFiles.size());
+        
+        Map actualDetails = (Map) actual.get("details");
+        assertTrue(actualDetails.containsKey("id"));
+        assertTrue(actualDetails.containsKey("name"));
+        assertTrue(actualDetails.containsKey("owner"));
+        assertTrue(actualDetails.containsKey("created"));
+        assertTrue(actualDetails.containsKey("modified"));
+        assertTrue(actualDetails.containsKey("lastAccess"));
+        
+        assertEquals(mockFolder.getId().longValue(), ((Number)actualDetails.get("id")).longValue());
+        assertEquals(mockFolder.getName(), actualDetails.get("name"));
+        assertEquals(mockFolder.getOwner(), actualDetails.get("owner"));
+        assertEquals(mockFolder.getCreated(), new Date((long) actualDetails.get("created")));
+        assertEquals(mockFolder.getModified(), new Date((long) actualDetails.get("modified")));
+        assertEquals(mockFolder.getLastAccess(), new Date((long) actualDetails.get("lastAccess")));
+
+    }
+
+}

java-math/src/main/java/com/baeldung/algorithms/gcd/GCDImplementation.java

@@ -0,0 +1,55 @@
+package com.baeldung.algorithms.gcd;
+
+public class GCDImplementation {
+
+    public static int gcdByBruteForce(int n1, int n2) {
+        int gcd = 1;
+        for (int i = 1; i <= n1 && i <= n2; i++) {
+            if (n1 % i == 0 && n2 % i == 0) {
+                gcd = i;
+            }
+        }
+        return gcd;
+    }
+
+    public static int gcdByEuclidsAlgorithm(int n1, int n2) {
+        if (n2 == 0) {
+            return n1;
+        }
+        return gcdByEuclidsAlgorithm(n2, n1 % n2);
+    }
+
+    public static int gcdBySteinsAlgorithm(int n1, int n2) {
+        if (n1 == 0) {
+            return n2;
+        }
+
+        if (n2 == 0) {
+            return n1;
+        }
+
+        int n;
+        for (n = 0; ((n1 | n2) & 1) == 0; n++) {
+            n1 >>= 1;
+            n2 >>= 1;
+        }
+
+        while ((n1 & 1) == 0) {
+            n1 >>= 1;
+        }
+
+        do {
+            while ((n2 & 1) == 0) {
+                n2 >>= 1;
+            }
+
+            if (n1 > n2) {
+                int temp = n1;
+                n1 = n2;
+                n2 = temp;
+            }
+            n2 = (n2 - n1);
+        } while (n2 != 0);
+        return n1 << n;
+    }
+}

java-math/src/test/java/com/baeldung/algorithms/gcd/GCDImplementationUnitTest.java

@@ -0,0 +1,32 @@
+package com.baeldung.algorithms.gcd;
+
+import org.junit.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class GCDImplementationUnitTest {
+
+    @Test
+    public void whenCalculatingGCDByBruteForceMethod_thenCorrect() {
+        int n1 = 60;
+        int n2 = 90;
+        int gcd = GCDImplementation.gcdByBruteForce(n1, n2);
+        assertThat(gcd).isEqualTo(30);
+    }
+
+    @Test
+    public void whenCalculatingGCDByEuclidsAlgorithm_thenCorrect() {
+        int n1 = 60;
+        int n2 = 90;
+        int gcd = GCDImplementation.gcdByEuclidsAlgorithm(n1, n2);
+        assertThat(gcd).isEqualTo(30);
+    }
+
+    @Test
+    public void whenCalculatingGCDBySteinsAlgorithm_thenCorrect() {
+        int n1 = 60;
+        int n2 = 90;
+        int gcd = GCDImplementation.gcdBySteinsAlgorithm(n1, n2);
+        assertThat(gcd).isEqualTo(30);
+    }
+}

parent-boot-1/pom.xml

@@ -55,7 +55,7 @@
 
 	<properties>
 		<rest-assured.version>3.1.0</rest-assured.version>
-		<spring-boot.version>1.5.19.RELEASE</spring-boot.version>
+		<spring-boot.version>1.5.22.RELEASE</spring-boot.version>
 	</properties>
 	
 </project>

parent-boot-2/pom.xml

@@ -78,6 +78,6 @@
         <rest-assured.version>3.3.0</rest-assured.version>
         <!-- plugins -->
         <thin.version>1.0.22.RELEASE</thin.version>
-        <spring-boot.version>2.1.6.RELEASE</spring-boot.version>
+        <spring-boot.version>2.1.7.RELEASE</spring-boot.version>
     </properties>
 </project>

patterns/backoff-jitter/README.md

@@ -1,2 +1,2 @@
 ### Relevant Articles:
-- [Better Retries with Exponential Backoff and Jitter](https://baeldung.com/retries-with-exponential-backoff-and-jitter)
+- [Better Retries with Exponential Backoff and Jitter](https://www.baeldung.com/resilience4j-backoff-jitter)

persistence-modules/java-sql2o/README.md

@@ -1,3 +1,3 @@
 ### Relevant Articles:
 
-- [A Guide to Sql2o](http://www.baeldung.com/sql2o)
+- [A Guide to Sql2o](https://www.baeldung.com/java-sql2o)

spring-all/README.md

@@ -11,7 +11,6 @@ The "REST With Spring" Classes: http://bit.ly/restwithspring
 ### Relevant articles:
 
 - [Guide to Spring @Autowired](http://www.baeldung.com/spring-autowire)
-- [Properties with Spring and Spring Boot](http://www.baeldung.com/properties-with-spring) - checkout the `org.baeldung.properties` package for all scenarios of properties injection and usage
 - [Spring Profiles](http://www.baeldung.com/spring-profiles)
 - [A Spring Custom Annotation for a Better DAO](http://www.baeldung.com/spring-annotation-bean-pre-processor)
 - [What’s New in Spring 4.3?](http://www.baeldung.com/whats-new-in-spring-4-3)

spring-boot-data/src/test/java/com/baeldung/disableautoconfig/SpringDataJPAIntegrationTest.java

@@ -19,7 +19,7 @@ public class SpringDataJPAIntegrationTest {
     private ApplicationContext context;
 
     @Test(expected = NoSuchBeanDefinitionException.class)
-    public void givenAutoconfigurationIsDisable_whenApplicationStarts_thenContextWillNotHaveTheAutoconfiguredClasses() {
+    public void givenAutoConfigDisabled_whenStarting_thenNoAutoconfiguredBeansInContext() {
         context.getBean(DataSource.class);
     }
 

spring-boot-data/src/test/java/com/baeldung/disableautoconfig/SpringDataMongoDBIntegrationTest.java

@@ -18,7 +18,7 @@ public class SpringDataMongoDBIntegrationTest {
     private ApplicationContext context;
 
     @Test(expected = NoSuchBeanDefinitionException.class)
-    public void givenAutoconfigurationIsDisable_whenApplicationStarts_thenContextWillNotHaveTheAutoconfiguredClasses() {
+    public void givenAutoConfigDisabled_whenStarting_thenNoAutoconfiguredBeansInContext() {
         context.getBean(MongoTemplate.class);
     }
 

spring-boot-data/src/test/java/com/baeldung/disableautoconfig/SpringDataRedisIntegrationTest.java

@@ -18,7 +18,7 @@ public class SpringDataRedisIntegrationTest {
     private ApplicationContext context;
 
     @Test(expected = NoSuchBeanDefinitionException.class)
-    public void givenAutoconfigurationIsDisable_whenApplicationStarts_thenContextWillNotHaveTheAutoconfiguredClasses() {
+    public void givenAutoConfigDisabled_whenStarting_thenNoAutoconfiguredBeansInContext() {
         context.getBean(RedisTemplate.class);
     }
 

spring-boot-properties/README.md

@@ -1,2 +1,10 @@
 ### Relevant Articles:
-- [Reloading Properties in Spring](https://www.baeldung.com/reloading-properties-files-in-spring/)
+- [Reloading Properties in Spring](https://www.baeldung.com/reloading-properties-files-in-spring/)
+- [Guide to @ConfigurationProperties in Spring Boot](http://www.baeldung.com/configuration-properties-in-spring-boot)
+- [Load Spring Boot Properties From a JSON File](https://www.baeldung.com/spring-boot-json-properties)
+- [Guide to @EnableConfigurationProperties](https://www.baeldung.com/spring-enable-config-properties)
+- [Properties with Spring and Spring Boot](http://www.baeldung.com/properties-with-spring) - checkout the `org.baeldung.properties` package for all scenarios of properties injection and usage
+- [A Quick Guide to Spring @Value](http://www.baeldung.com/spring-value-annotation)
+- [Spring YAML Configuration](http://www.baeldung.com/spring-yaml)
+- [Using Spring @Value with Defaults](http://www.baeldung.com/spring-value-defaults)
+- [How to Inject a Property Value Into a Class Not Managed by Spring?](http://www.baeldung.com/inject-properties-value-non-spring-class)

spring-boot-properties/pom.xml

@@ -37,6 +37,16 @@
             <artifactId>spring-boot-starter-test</artifactId>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>com.google.guava</groupId>
+            <artifactId>guava</artifactId>
+            <version>${guava.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.httpcomponents</groupId>
+            <artifactId>httpcore</artifactId>
+            <version>${httpcore.version}</version>
+        </dependency>
     </dependencies>
 
     <dependencyManagement>
@@ -99,6 +109,8 @@
         <java.version>1.8</java.version>
         <spring-cloud.version>Greenwich.SR1</spring-cloud.version>
         <commons-configuration.version>1.10</commons-configuration.version>
+        <guava.version>20.0</guava.version>
+        <httpcore.version>4.4.11</httpcore.version>
     </properties>
 
 </project>

spring-boot-properties/src/main/java/com/baeldung/properties/AdditionalConfiguration.java

@@ -1,4 +1,4 @@
-package org.baeldung.properties;
+package com.baeldung.properties;
 
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;

spring-boot-properties/src/main/java/com/baeldung/properties/AdditionalProperties.java

@@ -1,7 +1,9 @@
-package org.baeldung.properties;
+package com.baeldung.properties;
 
 import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.context.annotation.Configuration;
 
+@Configuration
 @ConfigurationProperties(prefix = "additional")
 public class AdditionalProperties {
 

spring-boot-properties/src/main/java/com/baeldung/properties/ConfigProperties.java

@@ -10,6 +10,7 @@ import javax.validation.constraints.Pattern;
 
 import org.hibernate.validator.constraints.Length;
 import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.PropertySource;
 import org.springframework.validation.annotation.Validated;
@@ -54,7 +55,7 @@ public class ConfigProperties {
     }
 
     @NotBlank
-    private String host;
+    private String hostName;
 
     @Min(1025)
     @Max(65536)
@@ -67,12 +68,12 @@ public class ConfigProperties {
     private List<String> defaultRecipients;
     private Map<String, String> additionalHeaders;
 
-    public String getHost() {
+    public String getHostName() {
-        return host;
+        return hostName;
     }
 
-    public void setHost(String host) {
+    public void setHostName(String hostName) {
-        this.host = host;
+        this.hostName = hostName;
     }
 
     public int getPort() {
@@ -114,4 +115,10 @@ public class ConfigProperties {
     public void setAdditionalHeaders(Map<String, String> additionalHeaders) {
         this.additionalHeaders = additionalHeaders;
     }
+    
+    @Bean
+    @ConfigurationProperties(prefix = "item")
+    public Item item(){
+        return new Item();
+    }
 }

spring-boot-properties/src/main/java/com/baeldung/properties/Item.java

@@ -1,4 +1,4 @@
-package org.baeldung.properties;
+package com.baeldung.properties;
 
 public class Item {
 

spring-boot-properties/src/main/resources/configprops.properties

@@ -22,3 +22,6 @@ item.name=Item name
 item.size=42
 
 
+#Additional properties
+additional.unit=km
+additional.max=100

spring-boot-properties/src/main/resources/conversion.properties

@@ -0,0 +1,2 @@
+conversion.timeInDefaultUnit=10
+conversion.timeInNano=9ns

spring-boot-properties/src/test/java/com/baeldung/properties/ConfigPropertiesIntegrationTest.java

@@ -1,8 +1,5 @@
 package com.baeldung.properties;
 
-import org.baeldung.properties.AdditionalProperties;
-import org.baeldung.properties.ConfigProperties;
-import org.baeldung.properties.ConfigPropertiesDemoApplication;
 import org.junit.Assert;
 import org.junit.Test;
 import org.junit.runner.RunWith;

spring-boot-properties/src/test/java/com/baeldung/properties/JsonPropertiesIntegrationTest.java

@@ -1,4 +1,4 @@
-package org.baeldung.properties;
+package com.baeldung.properties;
 
 import java.util.Arrays;
 

spring-boot-properties/src/test/resources/conversion.properties

@@ -0,0 +1,11 @@
+###### time unit
+conversion.timeInDefaultUnit=10
+conversion.timeInNano=9ns
+conversion.timeInDays=2
+
+###### data size
+conversion.sizeInDefaultUnit=300
+conversion.sizeInGB=2GB
+conversion.sizeInTB=4
+
+conversion.employee=john,2000

spring-boot/README.MD

@@ -14,7 +14,6 @@ The "REST With Spring" Classes: http://bit.ly/restwithspring
 - [Custom Information in Spring Boot Info Endpoint](http://www.baeldung.com/spring-boot-info-actuator-custom)
 - [Using @JsonComponent in Spring Boot](http://www.baeldung.com/spring-boot-jsoncomponent)
 - [Testing in Spring Boot](http://www.baeldung.com/spring-boot-testing)
-- [Guide to @ConfigurationProperties in Spring Boot](http://www.baeldung.com/configuration-properties-in-spring-boot)
 - [How to Get All Spring-Managed Beans?](http://www.baeldung.com/spring-show-all-beans)
 - [Spring Boot and Togglz Aspect](http://www.baeldung.com/spring-togglz)
 - [Getting Started with GraphQL and Spring Boot](http://www.baeldung.com/spring-graphql)
@@ -29,9 +28,7 @@ The "REST With Spring" Classes: http://bit.ly/restwithspring
 - [Spring Shutdown Callbacks](http://www.baeldung.com/spring-shutdown-callbacks)
 - [Container Configuration in Spring Boot 2](http://www.baeldung.com/embeddedservletcontainercustomizer-configurableembeddedservletcontainer-spring-boot)
 - [Introduction to Chaos Monkey](https://www.baeldung.com/spring-boot-chaos-monkey)
-- [Load Spring Boot Properties From a JSON File](https://www.baeldung.com/spring-boot-json-properties)
 - [Display Auto-Configuration Report in Spring Boot](https://www.baeldung.com/spring-boot-auto-configuration-report)
 - [Injecting Git Information Into Spring](https://www.baeldung.com/spring-git-information)
 - [Validation in Spring Boot](https://www.baeldung.com/spring-boot-bean-validation)
 - [Guide to Creating and Running a Jar File in Java](https://www.baeldung.com/java-create-jar)
-- [Guide to @EnableConfigurationProperties](https://www.baeldung.com/spring-enable-config-properties)

spring-boot/src/main/java/org/baeldung/properties/ConfigProperties.java

@@ -1,90 +0,0 @@
-package org.baeldung.properties;
-
-import java.util.List;
-import java.util.Map;
-
-import javax.validation.constraints.Max;
-import javax.validation.constraints.Min;
-import javax.validation.constraints.NotBlank;
-import javax.validation.constraints.Pattern;
-
-import org.springframework.boot.context.properties.ConfigurationProperties;
-import org.springframework.context.annotation.Bean;
-import org.springframework.context.annotation.Configuration;
-import org.springframework.context.annotation.PropertySource;
-import org.springframework.validation.annotation.Validated;
-
-@Configuration
-@PropertySource("classpath:configprops.properties")
-@ConfigurationProperties(prefix = "mail")
-@Validated
-public class ConfigProperties {
-
-    @NotBlank
-    private String hostName;
-
-    @Min(1025)
-    @Max(65536)
-    private int port;
-
-    @Pattern(regexp = "^[a-z0-9._%+-]+@[a-z0-9.-]+\\.[a-z]{2,6}$")
-    private String from;
-
-    private List<String> defaultRecipients;
-    private Map<String, String> additionalHeaders;
-    private Credentials credentials;
-
-    public String getHostName() {
-        return hostName;
-    }
-
-    public void setHostName(String hostName) {
-        this.hostName = hostName;
-    }
-
-    public int getPort() {
-        return port;
-    }
-
-    public void setPort(int port) {
-        this.port = port;
-    }
-
-    public String getFrom() {
-        return from;
-    }
-
-    public void setFrom(String from) {
-        this.from = from;
-    }
-
-    public List<String> getDefaultRecipients() {
-        return defaultRecipients;
-    }
-
-    public void setDefaultRecipients(List<String> defaultRecipients) {
-        this.defaultRecipients = defaultRecipients;
-    }
-
-    public Map<String, String> getAdditionalHeaders() {
-        return additionalHeaders;
-    }
-
-    public void setAdditionalHeaders(Map<String, String> additionalHeaders) {
-        this.additionalHeaders = additionalHeaders;
-    }
-
-    public Credentials getCredentials() {
-        return credentials;
-    }
-
-    public void setCredentials(Credentials credentials) {
-        this.credentials = credentials;
-    }
-
-    @Bean
-    @ConfigurationProperties(prefix = "item")
-    public Item item(){
-        return new Item();
-    }
-}

spring-boot/src/main/java/org/baeldung/properties/ConfigPropertiesDemoApplication.java

@@ -1,18 +0,0 @@
-package org.baeldung.properties;
-
-import org.springframework.boot.autoconfigure.SpringBootApplication;
-import org.springframework.boot.builder.SpringApplicationBuilder;
-import org.springframework.context.annotation.ComponentScan;
-
-@SpringBootApplication
-@ComponentScan(basePackageClasses = {ConfigProperties.class,
-        JsonProperties.class,
-        CustomJsonProperties.class,
-        AdditionalConfiguration.class})
-public class ConfigPropertiesDemoApplication {
-    public static void main(String[] args) {
-        new SpringApplicationBuilder(ConfigPropertiesDemoApplication.class).initializers(new JsonPropertyContextInitializer())
-                .run();
-    }
-
-}

spring-boot/src/main/java/org/baeldung/properties/Credentials.java

@@ -1,37 +0,0 @@
-package org.baeldung.properties;
-
-import org.hibernate.validator.constraints.Length;
-import org.springframework.validation.annotation.Validated;
-
-@Validated
-public class Credentials {
-
-    @Length(max = 4, min = 1)
-    private String authMethod;
-    private String username;
-    private String password;
-
-    public String getAuthMethod() {
-        return authMethod;
-    }
-
-    public void setAuthMethod(String authMethod) {
-        this.authMethod = authMethod;
-    }
-
-    public String getUsername() {
-        return username;
-    }
-
-    public void setUsername(String username) {
-        this.username = username;
-    }
-
-    public String getPassword() {
-        return password;
-    }
-
-    public void setPassword(String password) {
-        this.password = password;
-    }
-}

spring-boot/src/main/java/org/baeldung/properties/CustomJsonProperties.java

@@ -1,71 +0,0 @@
-package org.baeldung.properties;
-
-import org.springframework.boot.context.properties.ConfigurationProperties;
-import org.springframework.stereotype.Component;
-
-@Component
-@ConfigurationProperties(prefix = "custom")
-public class CustomJsonProperties {
-
-    private String host;
-
-    private int port;
-
-    private boolean resend;
-
-    private Person sender;
-
-    public static class Person {
-
-        private String name;
-        private String address;
-
-        public String getName() {
-            return name;
-        }
-
-        public void setName(String name) {
-            this.name = name;
-        }
-
-        public String getAddress() {
-            return address;
-        }
-
-        public void setAddress(String address) {
-            this.address = address;
-        }
-    }
-
-    public String getHost() {
-        return host;
-    }
-
-    public void setHost(String host) {
-        this.host = host;
-    }
-
-    public int getPort() {
-        return port;
-    }
-
-    public void setPort(int port) {
-        this.port = port;
-    }
-
-    public boolean isResend() {
-        return resend;
-    }
-
-    public void setResend(boolean resend) {
-        this.resend = resend;
-    }
-
-    public Person getSender() {
-        return sender;
-    }
-
-    public void setSender(Person sender) {
-        this.sender = sender;
-    }
-}

spring-boot/src/main/java/org/baeldung/properties/JsonProperties.java

@@ -1,64 +0,0 @@
-package org.baeldung.properties;
-
-import java.util.LinkedHashMap;
-import java.util.List;
-
-import org.springframework.boot.context.properties.ConfigurationProperties;
-import org.springframework.context.annotation.PropertySource;
-import org.springframework.stereotype.Component;
-
-@Component
-@PropertySource(value = "classpath:configprops.json", factory = JsonPropertySourceFactory.class)
-@ConfigurationProperties
-public class JsonProperties {
-
-    private String host;
-
-    private int port;
-
-    private boolean resend;
-
-    private List<String> topics;
-
-    private LinkedHashMap<String, ?> sender;
-
-    public LinkedHashMap<String, ?> getSender() {
-        return sender;
-    }
-
-    public void setSender(LinkedHashMap<String, ?> sender) {
-        this.sender = sender;
-    }
-
-    public List<String> getTopics() {
-        return topics;
-    }
-
-    public void setTopics(List<String> topics) {
-        this.topics = topics;
-    }
-
-    public int getPort() {
-        return port;
-    }
-
-    public void setPort(int port) {
-        this.port = port;
-    }
-
-    public boolean isResend() {
-        return resend;
-    }
-
-    public void setResend(boolean resend) {
-        this.resend = resend;
-    }
-
-    public String getHost() {
-        return host;
-    }
-
-    public void setHost(String host) {
-        this.host = host;
-    }
-}