Merge branch 'master' into master

apache-velocity/src/main/webapp/WEB-INF/velocity.properties

@@ -1,4 +1,4 @@
 resource.loader=webapp
 webapp.resource.loader.class=org.apache.velocity.tools.view.WebappResourceLoader
-webapp.resource.loader.path = .
+webapp.resource.loader.path = 
 webapp.resource.loader.cache = true

core-java-9/src/main/java/com/baeldung/java9/process/ServiceMain.java

@@ -6,7 +6,7 @@ public class ServiceMain {
 
     public static void main(String[] args) throws InterruptedException {
         ProcessHandle thisProcess = ProcessHandle.current();
-        long pid = thisProcess.getPid();
+        long pid = thisProcess.pid();
 
         Optional<String[]> opArgs = Optional.ofNullable(args);
         String procName = opArgs.map(str -> str.length > 0 ? str[0] : null).orElse(System.getProperty("sun.java.command"));

core-java-9/src/test/java/com/baeldung/java9/language/Java9ObjectsAPIUnitTest.java

@@ -0,0 +1,76 @@
+package com.baeldung.java9.language;
+
+import org.junit.Test;
+
+import java.util.Collections;
+import java.util.List;
+import java.util.Objects;
+
+import static org.hamcrest.Matchers.*;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+public class Java9ObjectsAPIUnitTest {
+    
+    @Test
+    public void givenNullObject_whenRequireNonNullElse_thenElse(){
+        assertThat(Objects.<List>requireNonNullElse(null, Collections.EMPTY_LIST),
+                is(Collections.EMPTY_LIST));
+    }
+
+    @Test
+    public void givenObject_whenRequireNonNullElse_thenObject(){
+        assertThat(Objects.<List>requireNonNullElse(List.of("item1", "item2"),
+                Collections.EMPTY_LIST), is(List.of("item1", "item2")));
+    }
+
+    @Test(expected = NullPointerException.class)
+    public void givenNull_whenRequireNonNullElse_thenException(){
+        Objects.<List>requireNonNullElse(null, null);
+    }
+
+    @Test
+    public void givenObject_whenRequireNonNullElseGet_thenObject(){
+        assertThat(Objects.<List>requireNonNullElseGet(null, List::of),
+                is(List.of()));
+    }
+
+    @Test
+    public void givenNumber_whenInvokeCheckIndex_thenNumber(){
+        int length = 5;
+        assertThat(Objects.checkIndex(4, length), is(4));
+    }
+
+    @Test(expected = IndexOutOfBoundsException.class)
+    public void givenOutOfRangeNumber_whenInvokeCheckIndex_thenException(){
+        int length = 5;
+        Objects.checkIndex(5, length);
+    }
+
+
+    @Test
+    public void givenSubRange_whenCheckFromToIndex_thenNumber(){
+        int length = 6;
+        assertThat(Objects.checkFromToIndex(2,length,length), is(2));
+    }
+
+    @Test(expected = IndexOutOfBoundsException.class)
+    public void givenInvalidSubRange_whenCheckFromToIndex_thenException(){
+        int length = 6;
+        Objects.checkFromToIndex(2,7,length);
+    }
+
+
+    @Test
+    public void givenSubRange_whenCheckFromIndexSize_thenNumber(){
+        int length = 6;
+        assertThat(Objects.checkFromIndexSize(2,3,length), is(2));
+    }
+
+    @Test(expected = IndexOutOfBoundsException.class)
+    public void givenInvalidSubRange_whenCheckFromIndexSize_thenException(){
+        int length = 6;
+        Objects.checkFromIndexSize(2, 6, length);
+    }
+
+
+}

junit5/pom.xml

@@ -3,7 +3,7 @@
     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>
 
-    <groupId>com.baeldung</groupId>
+    <!-- NOT NEEDED - JSP <groupId>com.baeldung</groupId>-->
     <artifactId>junit5</artifactId>
     <version>1.0-SNAPSHOT</version>
 
@@ -19,9 +19,9 @@
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <java.version>1.8</java.version>
-        <junit.jupiter.version>5.0.0-M5</junit.jupiter.version>
-        <junit.platform.version>1.0.0-M5</junit.platform.version>
-        <junit.vintage.version>4.12.0-M5</junit.vintage.version>
+        <junit.jupiter.version>5.0.0-RC2</junit.jupiter.version>
+        <junit.platform.version>1.0.0-RC2</junit.platform.version>
+        <junit.vintage.version>4.12.0-RC2</junit.vintage.version>
         <log4j2.version>2.8.2</log4j2.version>
         <h2.version>1.4.196</h2.version>
 

junit5/src/test/java/com/baeldung/param/InvalidPersonParameterResolver.java

@@ -0,0 +1,50 @@
+package com.baeldung.param;
+
+import java.util.Random;
+
+import org.junit.jupiter.api.extension.ExtensionContext;
+import org.junit.jupiter.api.extension.ParameterContext;
+import org.junit.jupiter.api.extension.ParameterResolutionException;
+import org.junit.jupiter.api.extension.ParameterResolver;
+
+public class InvalidPersonParameterResolver implements ParameterResolver {
+
+  /**
+   * The "bad" (invalid) data for testing purposes has to go somewhere, right?
+   */
+  public static Person[] INVALID_PERSONS = {
+      new Person().setId(1L).setLastName("Ad_ams").setFirstName("Jill,"),
+      new Person().setId(2L).setLastName(",Baker").setFirstName(""),
+      new Person().setId(3L).setLastName(null).setFirstName(null),
+      new Person().setId(4L).setLastName("Daniel&").setFirstName("{Joseph}"),
+      new Person().setId(5L).setLastName("").setFirstName("English, Jane"),
+      new Person()/* .setId(6L).setLastName("Fontana").setFirstName("Enrique") */,
+      // TODO: ADD MORE DATA HERE
+  };
+
+  @Override
+  public Object resolveParameter(ParameterContext parameterContext, ExtensionContext extensionContext)
+      throws ParameterResolutionException {
+    Object ret = null;
+    //
+    // Return a random, valid Person object if Person.class is the type of Parameter
+    /// to be resolved. Otherwise return null.
+    if (parameterContext.getParameter().getType() == Person.class) {
+      ret = INVALID_PERSONS[new Random().nextInt(INVALID_PERSONS.length)];
+    }
+    return ret;
+  }
+
+  @Override
+  public boolean supportsParameter(ParameterContext parameterContext, ExtensionContext extensionContext)
+      throws ParameterResolutionException {
+    boolean ret = false;
+    //
+    // If the Parameter.type == Person.class, then we support it, otherwise, get outta here!
+    if (parameterContext.getParameter().getType() == Person.class) {
+      ret = true;
+    }
+    return ret;
+  }
+
+}

junit5/src/test/java/com/baeldung/param/Person.java

@@ -0,0 +1,43 @@
+package com.baeldung.param;
+
+/**
+ * Very simple Person entity.
+ * Use the Fluent-style interface to set properties.
+ * 
+ * @author J Steven Perry
+ *
+ */
+public class Person {
+
+  private Long id;
+  private String lastName;
+  private String firstName;
+
+  public Long getId() {
+    return id;
+  }
+
+  public Person setId(Long id) {
+    this.id = id;
+    return this;
+  }
+
+  public String getLastName() {
+    return lastName;
+  }
+
+  public Person setLastName(String lastName) {
+    this.lastName = lastName;
+    return this;
+  }
+
+  public String getFirstName() {
+    return firstName;
+  }
+
+  public Person setFirstName(String firstName) {
+    this.firstName = firstName;
+    return this;
+  }
+
+}

junit5/src/test/java/com/baeldung/param/PersonValidator.java

@@ -0,0 +1,142 @@
+package com.baeldung.param;
+
+import java.util.Arrays;
+
+/**
+ * Somewhat contrived validation class to illustrate unit test
+ * concepts.
+ * 
+ * @author J Steven Perry
+ *
+ */
+public class PersonValidator {
+
+  /**
+   * Contrived checked exception to illustrate one possible
+   * way to handle validation errors (via a checked exception).
+   * 
+   * @author J Steven Perry
+   *
+   */
+  public static class ValidationException extends Exception {
+
+    /**
+     * 
+     */
+    private static final long serialVersionUID = -134518049431883102L;
+
+    // Probably should implement some more constructors, but don't want
+    /// to tarnish the lesson...
+
+    /**
+     * The one and only way to create this checked exception.
+     * 
+     * @param message
+     *          The message accompanying the exception. Should be meaningful.
+     */
+    public ValidationException(String message) {
+      super(message);
+
+    }
+
+  }
+
+  private static final String[] ILLEGAL_NAME_CHARACTERS = {
+      ",",
+      "_",
+      "{",
+      "}",
+      "!"
+  };
+
+  /**
+   * Validate the first name of the specified Person object.
+   * 
+   * @param person
+   *          The Person object to validate.
+   * 
+   * @return - returns true if the specified Person is valid
+   * 
+   * @throws ValidationException
+   *           - this Exception is thrown if any kind of validation error occurs.
+   */
+  public static boolean validateFirstName(Person person) throws ValidationException {
+    boolean ret = true;
+    // The validation rules go here.
+    // Naive: use simple ifs
+    if (person == null) {
+      throw new ValidationException("Person is null (not allowed)!");
+    }
+    if (person.getFirstName() == null) {
+      throw new ValidationException("Person FirstName is null (not allowed)!");
+    }
+    if (person.getFirstName().isEmpty()) {
+      throw new ValidationException("Person FirstName is an empty String (not allowed)!");
+    }
+    if (!isStringValid(person.getFirstName(), ILLEGAL_NAME_CHARACTERS)) {
+      throw new ValidationException(
+          "Person FirstName (" + person.getFirstName() + ") may not contain any of the following characters: "
+              + Arrays.toString(ILLEGAL_NAME_CHARACTERS)
+              + "!");
+    }
+    return ret;
+  }
+
+  /**
+   * Validate the last name of the specified Person object. Looks the same as first
+   * name? Look closer. Just kidding. It's the same. But real world code can (and will) diverge.
+   * 
+   * @param person
+   *          The Person object to validate.
+   * 
+   * @return - returns true if the specified Person is valid
+   * 
+   * @throws ValidationException
+   *           - this Exception is thrown if any kind of validation error occurs.
+   */
+  public static boolean validateLastName(Person person) throws ValidationException {
+    boolean ret = true;
+    // The validation rules go here.
+    // Naive: use simple ifs
+    if (person == null) {
+      throw new ValidationException("Person is null (not allowed)!");
+    }
+    if (person.getFirstName() == null) {
+      throw new ValidationException("Person FirstName is null (not allowed)!");
+    }
+    if (person.getFirstName().isEmpty()) {
+      throw new ValidationException("Person FirstName is an empty String (not allowed)!");
+    }
+    if (!isStringValid(person.getFirstName(), ILLEGAL_NAME_CHARACTERS)) {
+      throw new ValidationException(
+          "Person LastName (" + person.getLastName() + ") may not contain any of the following characters: "
+              + Arrays.toString(ILLEGAL_NAME_CHARACTERS)
+              + "!");
+    }
+    return ret;
+  }
+
+  /**
+   * Validates the specified name. If it contains any of the illegalCharacters,
+   * this method returns false (indicating the name is illegal). Otherwise it returns true.
+   * 
+   * @param candidate
+   *          The candidate String to validate
+   * 
+   * @param illegalCharacters
+   *          The characters the String is not allowed to have
+   * 
+   * @return - boolean - true if the name is valid, false otherwise.
+   */
+  private static boolean isStringValid(String candidate, String[] illegalCharacters) {
+    boolean ret = true;
+    for (String illegalChar : illegalCharacters) {
+      if (candidate.contains(illegalChar)) {
+        ret = false;
+        break;
+      }
+    }
+    return ret;
+  }
+
+}

junit5/src/test/java/com/baeldung/param/PersonValidatorTest.java

@@ -0,0 +1,102 @@
+package com.baeldung.param;
+
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.junit.jupiter.api.Assertions.fail;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.RepeatedTest;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.junit.platform.runner.JUnitPlatform;
+import org.junit.runner.RunWith;
+
+@RunWith(JUnitPlatform.class)
+@DisplayName("Testing PersonValidator")
+public class PersonValidatorTest {
+
+  /**
+   * Nested class, uses ExtendWith
+   * {@link com.baeldung.param.ValidPersonParameterResolver ValidPersonParameterResolver}
+   * to feed Test methods with "good" data.
+   */
+  @Nested
+  @DisplayName("When using Valid data")
+  @ExtendWith(ValidPersonParameterResolver.class)
+  public class ValidData {
+
+    /**
+     * Repeat the test ten times, that way we have a good shot at
+     * running all of the data through at least once.
+     * 
+     * @param person
+     *          A valid Person object to validate.
+     */
+    @RepeatedTest(value = 10)
+    @DisplayName("All first names are valid")
+    public void validateFirstName(Person person) {
+      try {
+        assertTrue(PersonValidator.validateFirstName(person));
+      } catch (PersonValidator.ValidationException e) {
+        fail("Exception not expected: " + e.getLocalizedMessage());
+      }
+    }
+
+    /**
+     * Repeat the test ten times, that way we have a good shot at
+     * running all of the data through at least once.
+     * 
+     * @param person
+     *          A valid Person object to validate.
+     */
+    @RepeatedTest(value = 10)
+    @DisplayName("All last names are valid")
+    public void validateLastName(Person person) {
+      try {
+        assertTrue(PersonValidator.validateLastName(person));
+      } catch (PersonValidator.ValidationException e) {
+        fail("Exception not expected: " + e.getLocalizedMessage());
+      }
+    }
+
+  }
+
+  /**
+   * Nested class, uses ExtendWith
+   * {@link com.baeldung.param.InvalidPersonParameterResolver InvalidPersonParameterResolver}
+   * to feed Test methods with "bad" data.
+   */
+  @Nested
+  @DisplayName("When using Invalid data")
+  @ExtendWith(InvalidPersonParameterResolver.class)
+  public class InvalidData {
+
+    /**
+     * Repeat the test ten times, that way we have a good shot at
+     * running all of the data through at least once.
+     * 
+     * @param person
+     *          An invalid Person object to validate.
+     */
+    @RepeatedTest(value = 10)
+    @DisplayName("All first names are invalid")
+    public void validateFirstName(Person person) {
+      assertThrows(PersonValidator.ValidationException.class, () -> PersonValidator.validateFirstName(person));
+    }
+
+    /**
+     * Repeat the test ten times, that way we have a good shot at
+     * running all of the data through at least once.
+     * 
+     * @param person
+     *          An invalid Person object to validate.
+     */
+    @RepeatedTest(value = 10)
+    @DisplayName("All first names are invalid")
+    public void validateLastName(Person person) {
+      assertThrows(PersonValidator.ValidationException.class, () -> PersonValidator.validateLastName(person));
+    }
+
+  }
+
+}

junit5/src/test/java/com/baeldung/param/ValidPersonParameterResolver.java

@@ -0,0 +1,50 @@
+package com.baeldung.param;
+
+import java.util.Random;
+
+import org.junit.jupiter.api.extension.ExtensionContext;
+import org.junit.jupiter.api.extension.ParameterContext;
+import org.junit.jupiter.api.extension.ParameterResolutionException;
+import org.junit.jupiter.api.extension.ParameterResolver;
+
+public class ValidPersonParameterResolver implements ParameterResolver {
+
+  /**
+   * The "good" (valid) data for testing purposes has to go somewhere, right?
+   */
+  public static Person[] VALID_PERSONS = {
+      new Person().setId(1L).setLastName("Adams").setFirstName("Jill"),
+      new Person().setId(2L).setLastName("Baker").setFirstName("James"),
+      new Person().setId(3L).setLastName("Carter").setFirstName("Samanta"),
+      new Person().setId(4L).setLastName("Daniels").setFirstName("Joseph"),
+      new Person().setId(5L).setLastName("English").setFirstName("Jane"),
+      new Person().setId(6L).setLastName("Fontana").setFirstName("Enrique"),
+      // TODO: ADD MORE DATA HERE
+  };
+
+  @Override
+  public Object resolveParameter(ParameterContext parameterContext, ExtensionContext extensionContext)
+      throws ParameterResolutionException {
+    Object ret = null;
+    //
+    // Return a random, valid Person object if Person.class is the type of Parameter
+    /// to be resolved. Otherwise return null.
+    if (parameterContext.getParameter().getType() == Person.class) {
+      ret = VALID_PERSONS[new Random().nextInt(VALID_PERSONS.length)];
+    }
+    return ret;
+  }
+
+  @Override
+  public boolean supportsParameter(ParameterContext parameterContext, ExtensionContext extensionContext)
+      throws ParameterResolutionException {
+    boolean ret = false;
+    //
+    // If the Parameter.type == Person.class, then we support it, otherwise, get outta here!
+    if (parameterContext.getParameter().getType() == Person.class) {
+      ret = true;
+    }
+    return ret;
+  }
+
+}

libraries/README.md

@@ -29,6 +29,8 @@
 - [Introduction to Neuroph](http://www.baeldung.com/intro-to-neuroph)
 - [Guide to Apache Commons CircularFifoQueue](http://www.baeldung.com/commons-circular-fifo-queue)
 - [Quick Guide to RSS with Rome](http://www.baeldung.com/rome-rss)
+- [Introduction to NoException](http://www.baeldung.com/intrduction-to-noexception)
+
 
 The libraries module contains examples related to small libraries that are relatively easy to use and does not require any separate module of its own.
 

libraries/pom.xml

@@ -462,6 +462,11 @@
 			<artifactId>pcollections</artifactId>
 			<version>${pcollections.version}</version>
 		</dependency>
+		<dependency>
+			<groupId>com.machinezoo.noexception</groupId>
+			<artifactId>noexception</artifactId>
+			<version>1.1.0</version>
+		</dependency>
     <dependency>
 			<groupId>org.eclipse.collections</groupId>
 			<artifactId>eclipse-collections</artifactId>

libraries/src/main/java/com/baeldung/noexception/CustomExceptionHandler.java

@@ -0,0 +1,24 @@
+package com.baeldung.noexception;
+
+import com.machinezoo.noexception.ExceptionHandler;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class CustomExceptionHandler extends ExceptionHandler {
+
+    private Logger logger = LoggerFactory.getLogger(CustomExceptionHandler.class);
+
+    @Override
+    public boolean handle(Throwable throwable) {
+
+        if (throwable.getClass()
+            .isAssignableFrom(RuntimeException.class)
+            || throwable.getClass()
+                .isAssignableFrom(Error.class)) {
+            return false;
+        } else {
+            logger.error("Caught Exception ", throwable);
+            return true;
+        }
+    }
+}

libraries/src/test/java/com/baeldung/eclipsecollections/ForEachPatternTest.java

@@ -0,0 +1,32 @@
+package com.baeldung.eclipsecollections;
+
+import org.eclipse.collections.api.block.procedure.Procedure;
+import org.eclipse.collections.api.tuple.Pair;
+import org.eclipse.collections.impl.map.mutable.UnifiedMap;
+import org.eclipse.collections.impl.tuple.Tuples;
+import static org.junit.Assert.assertEquals;
+
+import java.util.Map;
+
+import org.junit.Test;
+
+public class ForEachPatternTest {
+
+    @SuppressWarnings("unchecked")
+    @Test
+    public void whenInstantiateAndChangeValues_thenCorrect() {
+        Pair<Integer, String> pair1 = Tuples.pair(1, "One");
+        Pair<Integer, String> pair2 = Tuples.pair(2, "Two");
+        Pair<Integer, String> pair3 = Tuples.pair(3, "Three");
+
+        UnifiedMap<Integer, String> map = UnifiedMap.newMapWith(pair1, pair2, pair3);
+
+        for (int i = 0; i < map.size(); i++) {
+            map.put(i + 1, "New Value");
+        }
+
+        for (int i = 0; i < map.size(); i++) {
+            assertEquals("New Value", map.get(i + 1));
+        }
+    }
+}

libraries/src/test/java/com/baeldung/eclipsecollections/InjectIntoPatternTest.java

@@ -0,0 +1,23 @@
+package com.baeldung.eclipsecollections;
+
+import static org.junit.Assert.assertEquals;
+
+import java.util.List;
+
+import org.eclipse.collections.impl.factory.Lists;
+import org.junit.Test;
+
+public class InjectIntoPatternTest {
+
+    @Test
+    public void whenInjectInto_thenCorrect() {
+        List<Integer> list = Lists.mutable.of(1, 2, 3, 4);
+        int result = 5;
+        for (int i = 0; i < list.size(); i++) {
+            Integer v = list.get(i);
+            result = result + v.intValue();
+        }
+        
+        assertEquals(15, result);
+    }
+}

libraries/src/test/java/com/baeldung/hll/HLLUnitTest.java

@@ -23,9 +23,9 @@ public class HLLUnitTest {
 
         //when
         LongStream.range(0, numberOfElements).forEach(element -> {
-                    long hashedValue = hashFunction.newHasher().putLong(element).hash().asLong();
-                    hll.addRaw(hashedValue);
-                }
+              long hashedValue = hashFunction.newHasher().putLong(element).hash().asLong();
+              hll.addRaw(hashedValue);
+          }
         );
 
         //then
@@ -44,15 +44,15 @@ public class HLLUnitTest {
 
         //when
         LongStream.range(0, numberOfElements).forEach(element -> {
-                    long hashedValue = hashFunction.newHasher().putLong(element).hash().asLong();
-                    firstHll.addRaw(hashedValue);
-                }
+              long hashedValue = hashFunction.newHasher().putLong(element).hash().asLong();
+              firstHll.addRaw(hashedValue);
+          }
         );
 
         LongStream.range(numberOfElements, numberOfElements * 2).forEach(element -> {
-                    long hashedValue = hashFunction.newHasher().putLong(element).hash().asLong();
-                    secondHLL.addRaw(hashedValue);
-                }
+              long hashedValue = hashFunction.newHasher().putLong(element).hash().asLong();
+              secondHLL.addRaw(hashedValue);
+          }
         );
 
         //then

libraries/src/test/java/com/baeldung/hoverfly/HoverflyApiIntegrationTest.java

@@ -31,7 +31,7 @@ import org.springframework.web.client.RestTemplate;
 import io.specto.hoverfly.junit.core.SimulationSource;
 import io.specto.hoverfly.junit.rule.HoverflyRule;
 
-public class HoverflyApiTest {
+public class HoverflyApiIntegrationTest {
 
     private static final SimulationSource source = dsl(
       service("http://www.baeldung.com")

libraries/src/test/java/com/baeldung/noexception/NoExceptionUnitTest.java

@@ -0,0 +1,62 @@
+package com.baeldung.noexception;
+
+import com.machinezoo.noexception.Exceptions;
+import org.junit.Test;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class NoExceptionUnitTest {
+
+    private static Logger logger = LoggerFactory.getLogger(NoExceptionUnitTest.class);
+
+    @Test
+    public void whenStdExceptionHandling_thenCatchAndLog() {
+        try {
+            System.out.println("Result is " + Integer.parseInt("foobar"));
+        } catch (Throwable exception) {
+            logger.error("Caught exception:", exception);
+        }
+    }
+
+    @Test
+    public void whenDefaultNoException_thenCatchAndLog() {
+        Exceptions.log().run(() -> System.out.println("Result is " + Integer.parseInt("foobar")));
+    }
+
+    @Test
+    public void givenLogger_whenDefaultNoException_thenCatchAndLogWithClassName() {
+        Exceptions.log(logger).run(() -> System.out.println("Result is " + Integer.parseInt("foobar")));
+    }
+
+    @Test
+    public void givenLoggerAndMessage_whenDefaultNoException_thenCatchAndLogWithMessage() {
+        Exceptions.log(logger, "Something went wrong:").run(() -> System.out.println("Result is " + Integer.parseInt("foobar")));
+    }
+
+    @Test
+    public void givenDefaultValue_whenDefaultNoException_thenCatchAndLogPrintDefault() {
+        System.out.println("Result is " + Exceptions.log(logger, "Something went wrong:").get(() -> Integer.parseInt("foobar")).orElse(-1));
+    }
+
+    @Test(expected = Error.class)
+    public void givenCustomHandler_whenError_thenRethrowError() {
+        CustomExceptionHandler customExceptionHandler = new CustomExceptionHandler();
+        customExceptionHandler.run(() -> throwError());
+    }
+
+    @Test
+    public void givenCustomHandler_whenException_thenCatchAndLog() {
+        CustomExceptionHandler customExceptionHandler = new CustomExceptionHandler();
+        customExceptionHandler.run(() -> throwException());
+    }
+
+    private static void throwError() {
+        throw new Error("This is very bad.");
+    }
+
+    private static void throwException() {
+        String testString = "foo";
+        testString.charAt(5);
+    }
+
+}

libraries/src/test/java/com/baeldung/pcollections/PCollectionsUnitTest.java

@@ -1,7 +1,12 @@
 package com.baeldung.pcollections;
 
 import org.junit.Test;
-import org.pcollections.*;
+import org.pcollections.HashPMap;
+import org.pcollections.HashTreePMap;
+import org.pcollections.HashTreePSet;
+import org.pcollections.MapPSet;
+import org.pcollections.PVector;
+import org.pcollections.TreePVector;
 
 import java.util.Arrays;
 import java.util.HashMap;
@@ -27,7 +32,7 @@ public class PCollectionsUnitTest {
 
     @Test
     public void givenExistingHashMap_whenFrom_thenCreateHashPMap() {
-        Map map = new HashMap();
+        Map<String, String> map = new HashMap<>();
         map.put("mkey1", "mval1");
         map.put("mkey2", "mval2");
 
@@ -41,7 +46,7 @@ public class PCollectionsUnitTest {
         HashPMap<String, String> pmap = HashTreePMap.empty();
         HashPMap<String, String> pmap0 = pmap.plus("key1", "value1");
 
-        Map map = new HashMap();
+        Map<String, String> map = new HashMap<>();
         map.put("key2", "val2");
         map.put("key3", "val3");
 
@@ -57,22 +62,24 @@ public class PCollectionsUnitTest {
 
     @Test
     public void whenTreePVectorMethods_thenPerformOperations() {
-        TreePVector pVector = TreePVector.empty();
+        TreePVector<String> pVector = TreePVector.empty();
+
+        TreePVector<String> pV1 = pVector.plus("e1");
+        TreePVector<String> pV2 = pV1.plusAll(Arrays.asList("e2", "e3", "e4"));
 
-        TreePVector pV1 = pVector.plus("e1");
-        TreePVector pV2 = pV1.plusAll(Arrays.asList("e2", "e3", "e4"));
         assertEquals(1, pV1.size());
         assertEquals(4, pV2.size());
 
-        TreePVector pV3 = pV2.minus("e1");
-        TreePVector pV4 = pV3.minusAll(Arrays.asList("e2", "e3", "e4"));
+        TreePVector<String> pV3 = pV2.minus("e1");
+        TreePVector<String> pV4 = pV3.minusAll(Arrays.asList("e2", "e3", "e4"));
+
         assertEquals(pV3.size(), 3);
         assertEquals(pV4.size(), 0);
 
-        TreePVector pSub = pV2.subList(0, 2);
+        TreePVector<String> pSub = pV2.subList(0, 2);
         assertTrue(pSub.contains("e1") && pSub.contains("e2"));
 
-        TreePVector pVW = (TreePVector) pV2.with(0, "e10");
+        PVector<String> pVW = pV2.with(0, "e10");
         assertEquals(pVW.get(0), "e10");
     }
 
@@ -80,7 +87,7 @@ public class PCollectionsUnitTest {
     public void whenMapPSetMethods_thenPerformOperations() {
 
         MapPSet pSet = HashTreePSet.empty()
-                .plusAll(Arrays.asList("e1","e2","e3","e4"));
+          .plusAll(Arrays.asList("e1", "e2", "e3", "e4"));
         assertEquals(pSet.size(), 4);
 
         MapPSet pSet1 = pSet.minus("e4");

metrics/src/test/java/com/baeldung/metrics/servo/AtlasObserverLiveTest.java

@@ -27,9 +27,6 @@ import static org.hamcrest.CoreMatchers.containsString;
 import static org.hamcrest.CoreMatchers.not;
 import static org.junit.Assert.assertThat;
 
-/**
- * @author aiet
- */
 public class AtlasObserverLiveTest {
 
     private final String atlasUri = "http://localhost:7101/api/v1";

metrics/src/test/java/com/baeldung/metrics/servo/MetricAnnotationManualTest.java

@@ -22,10 +22,7 @@ import static org.hamcrest.Matchers.*;
 import static org.junit.Assert.assertThat;
 import static org.junit.Assert.assertTrue;
 
-/**
- * @author aiet
- */
-public class MetricAnnotationTest extends MetricTestBase {
+public class MetricAnnotationManualTest extends MetricTestBase {
 
     @Monitor(name = "integerCounter", type = DataSourceType.COUNTER, description = "Total number of update operations.")
     private final AtomicInteger updateCount = new AtomicInteger(0);

metrics/src/test/java/com/baeldung/metrics/servo/MetricObserverManualTest.java

@@ -13,14 +13,16 @@ import java.util.List;
 
 import static com.netflix.servo.annotations.DataSourceType.GAUGE;
 import static java.util.concurrent.TimeUnit.SECONDS;
-import static org.hamcrest.Matchers.*;
+import static org.hamcrest.Matchers.allOf;
+import static org.hamcrest.Matchers.greaterThanOrEqualTo;
+import static org.hamcrest.Matchers.hasItem;
+import static org.hamcrest.Matchers.hasProperty;
+import static org.hamcrest.Matchers.hasSize;
+import static org.hamcrest.Matchers.is;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertThat;
 
-/**
- * @author aiet
- */
-public class MetricObserverTest extends MetricTestBase {
+public class MetricObserverManualTest extends MetricTestBase {
 
     @Test
     public void givenMetrics_whenRegister_thenMonitored() throws InterruptedException {

metrics/src/test/java/com/baeldung/metrics/servo/MetricPollerManualTest.java

@@ -1,20 +1,23 @@
 package com.baeldung.metrics.servo;
 
 import com.netflix.servo.Metric;
-import com.netflix.servo.publish.*;
+import com.netflix.servo.publish.BasicMetricFilter;
+import com.netflix.servo.publish.JvmMetricPoller;
+import com.netflix.servo.publish.MemoryMetricObserver;
+import com.netflix.servo.publish.PollRunnable;
+import com.netflix.servo.publish.PollScheduler;
 import org.junit.Test;
 
 import java.util.List;
 
 import static java.util.concurrent.TimeUnit.SECONDS;
 import static java.util.stream.Collectors.toList;
-import static org.hamcrest.Matchers.*;
+import static org.hamcrest.Matchers.greaterThanOrEqualTo;
+import static org.hamcrest.Matchers.hasItems;
+import static org.hamcrest.Matchers.hasSize;
 import static org.junit.Assert.assertThat;
 
-/**
- * @author aiet
- */
-public class MetricPollerTest {
+public class MetricPollerManualTest {
 
     @Test
     public void givenJvmPoller_whenMonitor_thenDataCollected() throws Exception {

metrics/src/test/java/com/baeldung/metrics/servo/MetricTestBase.java

@@ -1,14 +1,16 @@
 package com.baeldung.metrics.servo;
 
-import com.netflix.servo.publish.*;
+import com.netflix.servo.publish.BasicMetricFilter;
+import com.netflix.servo.publish.MemoryMetricObserver;
+import com.netflix.servo.publish.MetricFilter;
+import com.netflix.servo.publish.MonitorRegistryMetricPoller;
+import com.netflix.servo.publish.PollRunnable;
+import com.netflix.servo.publish.PollScheduler;
 import org.junit.After;
 import org.junit.Before;
 
 import static java.util.concurrent.TimeUnit.SECONDS;
 
-/**
- * @author aiet
- */
 abstract class MetricTestBase {
 
     MemoryMetricObserver observer;

metrics/src/test/java/com/baeldung/metrics/servo/MetricTypeTest.java

@@ -1,6 +1,21 @@
 package com.baeldung.metrics.servo;
 
-import com.netflix.servo.monitor.*;
+import com.netflix.servo.monitor.BasicCounter;
+import com.netflix.servo.monitor.BasicGauge;
+import com.netflix.servo.monitor.BasicInformational;
+import com.netflix.servo.monitor.BasicTimer;
+import com.netflix.servo.monitor.BucketConfig;
+import com.netflix.servo.monitor.BucketTimer;
+import com.netflix.servo.monitor.Counter;
+import com.netflix.servo.monitor.Gauge;
+import com.netflix.servo.monitor.MaxGauge;
+import com.netflix.servo.monitor.Monitor;
+import com.netflix.servo.monitor.MonitorConfig;
+import com.netflix.servo.monitor.Monitors;
+import com.netflix.servo.monitor.PeakRateCounter;
+import com.netflix.servo.monitor.StatsTimer;
+import com.netflix.servo.monitor.StepCounter;
+import com.netflix.servo.monitor.Stopwatch;
 import com.netflix.servo.stats.StatsConfig;
 import org.junit.Ignore;
 import org.junit.Test;
@@ -9,13 +24,12 @@ import java.util.Map;
 
 import static java.util.concurrent.TimeUnit.SECONDS;
 import static java.util.stream.Collectors.toMap;
-import static org.hamcrest.Matchers.*;
+import static org.hamcrest.Matchers.allOf;
+import static org.hamcrest.Matchers.containsInAnyOrder;
+import static org.hamcrest.Matchers.hasEntry;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertThat;
 
-/**
- * Unit test for simple App.
- */
 public class MetricTypeTest {
 
     @Test
@@ -113,7 +127,7 @@ public class MetricTypeTest {
         BucketTimer timer = new BucketTimer(MonitorConfig
           .builder("test")
           .build(), new BucketConfig.Builder()
-          .withBuckets(new long[] { 2L, 5L })
+          .withBuckets(new long[]{2L, 5L})
           .withTimeUnit(SECONDS)
           .build(), SECONDS);
         timer.record(3);
@@ -150,7 +164,7 @@ public class MetricTypeTest {
           .builder("test")
           .build(), new StatsConfig.Builder()
           .withComputeFrequencyMillis(2000)
-          .withPercentiles(new double[] { 99.0, 95.0, 90.0 })
+          .withPercentiles(new double[]{99.0, 95.0, 90.0})
           .withPublishMax(true)
           .withPublishMin(true)
           .withPublishCount(true)

noexception/README.md

@@ -0,0 +1,2 @@
+### Relevant Articles:
+- [Introduction to NoException](http://www.baeldung.com/intrduction-to-noexception)

noexception/pom.xml

@@ -0,0 +1,23 @@
+<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/maven-v4_0_0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>com.baeldung</groupId>
+    <artifactId>noexception</artifactId>
+    <version>1.0</version>
+    <name>noexception</name>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>com.machinezoo.noexception</groupId>
+            <artifactId>noexception</artifactId>
+            <version>1.1.0</version>
+        </dependency>
+    </dependencies>
+</project>

noexception/src/main/java/com/baeldung/noexception/CustomExceptionHandler.java

@@ -0,0 +1,24 @@
+package com.baeldung.noexception;
+
+import com.machinezoo.noexception.ExceptionHandler;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class CustomExceptionHandler extends ExceptionHandler {
+
+    private Logger logger = LoggerFactory.getLogger(CustomExceptionHandler.class);
+
+    @Override
+    public boolean handle(Throwable throwable) {
+
+        if (throwable.getClass()
+            .isAssignableFrom(RuntimeException.class)
+            || throwable.getClass()
+                .isAssignableFrom(Error.class)) {
+            return false;
+        } else {
+            logger.error("Caught Exception ", throwable);
+            return true;
+        }
+    }
+}

noexception/src/test/java/com/baeldung/noexception/NoExceptionUnitTest.java

@@ -0,0 +1,63 @@
+package com.baeldung.noexception;
+
+import com.machinezoo.noexception.Exceptions;
+import org.junit.Test;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class NoExceptionUnitTest {
+
+    private static Logger logger = LoggerFactory.getLogger(NoExceptionUnitTest.class);
+
+    @Test
+    public void whenStdExceptionHandling_thenCatchAndLog() {
+        try {
+            System.out.println("Result is " + Integer.parseInt("foobar"));
+        } catch (Throwable exception) {
+            logger.error("Caught exception:", exception);
+        }
+    }
+
+    @Test
+    public void whenDefaultNoException_thenCatchAndLog() {
+
+        Exceptions.log().run(() -> System.out.println("Result is " + Integer.parseInt("foobar")));
+    }
+
+    @Test
+    public void givenLogger_whenDefaultNoException_thenCatchAndLogWithClassName() {
+        System.out.println("Result is " + Exceptions.log(logger).get(() -> +Integer.parseInt("foobar")).orElse(-1));
+    }
+
+    @Test
+    public void givenLoggerAndMessage_whenDefaultNoException_thenCatchAndLogWithClassNameAndMessage() {
+        System.out.println("Result is " + Exceptions.log(logger, "Something went wrong:").get(() -> +Integer.parseInt("foobar")).orElse(-1));
+    }
+
+    @Test
+    public void givenDefaultValue_whenDefaultNoException_thenCatchAndLogPrintDefault() {
+        System.out.println("Result is " + Exceptions.log(logger, "Something went wrong:").get(() -> +Integer.parseInt("foobar")).orElse(-1));
+    }
+
+    @Test(expected = Error.class)
+    public void givenCustomHandler_whenError_thenRethrowError() {
+        CustomExceptionHandler customExceptionHandler = new CustomExceptionHandler();
+        customExceptionHandler.run(() -> throwError());
+    }
+
+    @Test
+    public void givenCustomHandler_whenException_thenCatchAndLog() {
+        CustomExceptionHandler customExceptionHandler = new CustomExceptionHandler();
+        customExceptionHandler.run(() -> throwException());
+    }
+
+    private static void throwError() {
+        throw new Error("This is very bad.");
+    }
+
+    private static void throwException() {
+        String testString = "foo";
+        testString.charAt(5);
+    }
+
+}

pom.xml

@@ -106,6 +106,7 @@
         <module>mockito2</module>
         <module>mocks</module>
         <module>mustache</module>
+        <module>noexception</module>
 
         <module>orika</module>
 

spring-activiti/src/test/java/com/example/activitiwithspring/ProcessEngineCreationIntegrationTest.java

@@ -3,11 +3,12 @@ package com.example.activitiwithspring;
 import org.activiti.engine.ProcessEngine;
 import org.activiti.engine.ProcessEngineConfiguration;
 import org.activiti.engine.ProcessEngines;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNotNull;
 import org.junit.Test;
 
-public class ProcessEngineCreationTests {
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+
+public class ProcessEngineCreationIntegrationTest {
 
     @Test
     public void givenXMLConfig_whenGetDefault_thenGotProcessEngine() {
@@ -35,7 +36,7 @@ public class ProcessEngineCreationTests {
     @Test
     public void givenDifferentBeanNameInXMLConfig_whenGetProcessEngineConfig_thenGotResult() {
         ProcessEngineConfiguration processEngineConfiguration = ProcessEngineConfiguration
-                .createProcessEngineConfigurationFromResource("my.activiti.cfg.xml", "myProcessEngineConfiguration");
+          .createProcessEngineConfigurationFromResource("my.activiti.cfg.xml", "myProcessEngineConfiguration");
         ProcessEngine processEngine = processEngineConfiguration.buildProcessEngine();
         assertNotNull(processEngine);
         assertEquals("baeldung", processEngine.getProcessEngineConfiguration().getJdbcUsername());
@@ -45,8 +46,8 @@ public class ProcessEngineCreationTests {
     public void givenNoXMLConfig_whenCreateInMemProcessEngineConfig_thenCreated() {
         ProcessEngineConfiguration processEngineConfiguration = ProcessEngineConfiguration.createStandaloneInMemProcessEngineConfiguration();
         ProcessEngine processEngine = processEngineConfiguration
-                .setJdbcUrl("jdbc:h2:mem:my-own-in-mem-db;DB_CLOSE_DELAY=1000")
-                .buildProcessEngine();
+          .setJdbcUrl("jdbc:h2:mem:my-own-in-mem-db;DB_CLOSE_DELAY=1000")
+          .buildProcessEngine();
         assertNotNull(processEngine);
         assertEquals("sa", processEngine.getProcessEngineConfiguration().getJdbcUsername());
     }
@@ -55,9 +56,9 @@ public class ProcessEngineCreationTests {
     public void givenNoXMLConfig_whenCreateProcessEngineConfig_thenCreated() {
         ProcessEngineConfiguration processEngineConfiguration = ProcessEngineConfiguration.createStandaloneProcessEngineConfiguration();
         ProcessEngine processEngine = processEngineConfiguration
-                .setDatabaseSchemaUpdate(ProcessEngineConfiguration.DB_SCHEMA_UPDATE_TRUE)
-                .setJdbcUrl("jdbc:h2:mem:my-own-db;DB_CLOSE_DELAY=1000")
-                .buildProcessEngine();
+          .setDatabaseSchemaUpdate(ProcessEngineConfiguration.DB_SCHEMA_UPDATE_TRUE)
+          .setJdbcUrl("jdbc:h2:mem:my-own-db;DB_CLOSE_DELAY=1000")
+          .buildProcessEngine();
         assertNotNull(processEngine);
         assertEquals("sa", processEngine.getProcessEngineConfiguration().getJdbcUsername());
     }

spring-activiti/src/test/java/com/example/activitiwithspring/ProcessExecutionIntegrationTest.java

@@ -1,10 +1,6 @@
 package com.example.activitiwithspring;
 
 
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-
 import org.activiti.engine.ActivitiException;
 import org.activiti.engine.ProcessEngine;
 import org.activiti.engine.ProcessEngines;
@@ -13,19 +9,24 @@ import org.activiti.engine.RuntimeService;
 import org.activiti.engine.TaskService;
 import org.activiti.engine.runtime.ProcessInstance;
 import org.activiti.engine.task.Task;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertTrue;
 import org.junit.Test;
 
-public class ProcessExecutionTests {
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+
+public class ProcessExecutionIntegrationTest {
 
     @Test
     public void givenBPMN_whenDeployProcess_thenDeployed() {
         ProcessEngine processEngine = ProcessEngines.getDefaultProcessEngine();
         RepositoryService repositoryService = processEngine.getRepositoryService();
         repositoryService.createDeployment()
-                .addClasspathResource("org/activiti/test/vacationRequest.bpmn20.xml")
-                .deploy();
+          .addClasspathResource("org/activiti/test/vacationRequest.bpmn20.xml")
+          .deploy();
         Long count = repositoryService.createProcessDefinitionQuery().count();
         assertTrue(count >= 1);
     }
@@ -35,8 +36,8 @@ public class ProcessExecutionTests {
         ProcessEngine processEngine = ProcessEngines.getDefaultProcessEngine();
         RepositoryService repositoryService = processEngine.getRepositoryService();
         repositoryService.createDeployment()
-                .addClasspathResource("org/activiti/test/vacationRequest.bpmn20.xml")
-                .deploy();
+          .addClasspathResource("org/activiti/test/vacationRequest.bpmn20.xml")
+          .deploy();
 
         Map<String, Object> variables = new HashMap<String, Object>();
         variables.put("employeeName", "Kermit");
@@ -45,7 +46,7 @@ public class ProcessExecutionTests {
 
         RuntimeService runtimeService = processEngine.getRuntimeService();
         ProcessInstance processInstance = runtimeService
-                .startProcessInstanceByKey("vacationRequest", variables);
+          .startProcessInstanceByKey("vacationRequest", variables);
 
         Long count = runtimeService.createProcessInstanceQuery().count();
         assertTrue(count >= 1);
@@ -56,8 +57,8 @@ public class ProcessExecutionTests {
         ProcessEngine processEngine = ProcessEngines.getDefaultProcessEngine();
         RepositoryService repositoryService = processEngine.getRepositoryService();
         repositoryService.createDeployment()
-                .addClasspathResource("org/activiti/test/vacationRequest.bpmn20.xml")
-                .deploy();
+          .addClasspathResource("org/activiti/test/vacationRequest.bpmn20.xml")
+          .deploy();
 
         Map<String, Object> variables = new HashMap<String, Object>();
         variables.put("employeeName", "Kermit");
@@ -66,7 +67,7 @@ public class ProcessExecutionTests {
 
         RuntimeService runtimeService = processEngine.getRuntimeService();
         ProcessInstance processInstance = runtimeService
-                .startProcessInstanceByKey("vacationRequest", variables);
+          .startProcessInstanceByKey("vacationRequest", variables);
 
         TaskService taskService = processEngine.getTaskService();
         List<Task> tasks = taskService.createTaskQuery().taskCandidateGroup("management").list();
@@ -87,8 +88,8 @@ public class ProcessExecutionTests {
         ProcessEngine processEngine = ProcessEngines.getDefaultProcessEngine();
         RepositoryService repositoryService = processEngine.getRepositoryService();
         repositoryService.createDeployment()
-                .addClasspathResource("org/activiti/test/vacationRequest.bpmn20.xml")
-                .deploy();
+          .addClasspathResource("org/activiti/test/vacationRequest.bpmn20.xml")
+          .deploy();
 
         RuntimeService runtimeService = processEngine.getRuntimeService();
         repositoryService.suspendProcessDefinitionByKey("vacationRequest");

spring-batch/src/main/java/org/baeldung/spring_batch_intro/partitioner/CustomMultiResourcePartitioner.java

@@ -0,0 +1,77 @@
+/*
+ * Copyright 2006-2013 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.baeldung.spring_batch_intro.partitioner;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import org.springframework.batch.core.partition.support.Partitioner;
+import org.springframework.batch.item.ExecutionContext;
+import org.springframework.core.io.Resource;
+import org.springframework.util.Assert;
+
+public class CustomMultiResourcePartitioner implements Partitioner {
+
+    private static final String DEFAULT_KEY_NAME = "fileName";
+
+    private static final String PARTITION_KEY = "partition";
+
+    private Resource[] resources = new Resource[0];
+
+    private String keyName = DEFAULT_KEY_NAME;
+
+    /**
+     * The resources to assign to each partition. In Spring configuration you
+     * can use a pattern to select multiple resources.
+     * @param resources the resources to use
+     */
+    public void setResources(Resource[] resources) {
+        this.resources = resources;
+    }
+
+    /**
+     * The name of the key for the file name in each {@link ExecutionContext}.
+     * Defaults to "fileName".
+     * @param keyName the value of the key
+     */
+    public void setKeyName(String keyName) {
+        this.keyName = keyName;
+    }
+
+    /**
+     * Assign the filename of each of the injected resources to an
+     * {@link ExecutionContext}.
+     *
+     * @see Partitioner#partition(int)
+     */
+    @Override
+    public Map<String, ExecutionContext> partition(int gridSize) {
+        Map<String, ExecutionContext> map = new HashMap<String, ExecutionContext>(gridSize);
+        int i = 0, k = 1;
+        for (Resource resource : resources) {
+            ExecutionContext context = new ExecutionContext();
+            Assert.state(resource.exists(), "Resource does not exist: " + resource);
+            context.putString(keyName, resource.getFilename());
+            context.putString("opFileName", "output" + k++ + ".xml");
+
+            map.put(PARTITION_KEY + i, context);
+            i++;
+        }
+        return map;
+    }
+
+}

spring-batch/src/main/java/org/baeldung/spring_batch_intro/partitioner/SpringbatchPartitionConfig.java

@@ -0,0 +1,169 @@
+package org.baeldung.spring_batch_intro.partitioner;
+
+import java.io.IOException;
+import java.net.MalformedURLException;
+import java.text.ParseException;
+
+import javax.sql.DataSource;
+
+import org.baeldung.spring_batch_intro.model.Transaction;
+import org.baeldung.spring_batch_intro.service.RecordFieldSetMapper;
+import org.springframework.batch.core.Job;
+import org.springframework.batch.core.Step;
+import org.springframework.batch.core.configuration.annotation.EnableBatchProcessing;
+import org.springframework.batch.core.configuration.annotation.JobBuilderFactory;
+import org.springframework.batch.core.configuration.annotation.StepBuilderFactory;
+import org.springframework.batch.core.configuration.annotation.StepScope;
+import org.springframework.batch.core.launch.JobLauncher;
+import org.springframework.batch.core.launch.support.SimpleJobLauncher;
+import org.springframework.batch.core.repository.JobRepository;
+import org.springframework.batch.core.repository.support.JobRepositoryFactoryBean;
+import org.springframework.batch.item.UnexpectedInputException;
+import org.springframework.batch.item.file.FlatFileItemReader;
+import org.springframework.batch.item.file.mapping.DefaultLineMapper;
+import org.springframework.batch.item.file.transform.DelimitedLineTokenizer;
+import org.springframework.batch.item.xml.StaxEventItemWriter;
+import org.springframework.batch.support.transaction.ResourcelessTransactionManager;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.core.io.ClassPathResource;
+import org.springframework.core.io.FileSystemResource;
+import org.springframework.core.io.Resource;
+import org.springframework.core.io.support.ResourcePatternResolver;
+import org.springframework.core.task.TaskExecutor;
+import org.springframework.jdbc.datasource.embedded.EmbeddedDatabase;
+import org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseBuilder;
+import org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseType;
+import org.springframework.oxm.Marshaller;
+import org.springframework.oxm.jaxb.Jaxb2Marshaller;
+import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
+import org.springframework.transaction.PlatformTransactionManager;
+
+@Configuration
+@EnableBatchProcessing
+public class SpringbatchPartitionConfig {
+
+    @Autowired
+    ResourcePatternResolver resoursePatternResolver;
+
+    @Autowired
+    private JobBuilderFactory jobs;
+
+    @Autowired
+    private StepBuilderFactory steps;
+
+    @Bean(name = "partitionerJob")
+    public Job partitionerJob() throws UnexpectedInputException, MalformedURLException, ParseException {
+        return jobs.get("partitionerJob")
+            .start(partitionStep())
+            .build();
+    }
+
+    @Bean
+    public Step partitionStep() throws UnexpectedInputException, MalformedURLException, ParseException {
+        return steps.get("partitionStep")
+            .partitioner("slaveStep", partitioner())
+            .step(slaveStep())
+            .taskExecutor(taskExecutor())
+            .build();
+    }
+
+    @Bean
+    public Step slaveStep() throws UnexpectedInputException, MalformedURLException, ParseException {
+        return steps.get("slaveStep")
+            .<Transaction, Transaction> chunk(1)
+            .reader(itemReader(null))
+            .writer(itemWriter(marshaller(), null))
+            .build();
+    }
+
+    @Bean
+    public CustomMultiResourcePartitioner partitioner() {
+        CustomMultiResourcePartitioner partitioner = new CustomMultiResourcePartitioner();
+        Resource[] resources;
+        try {
+            resources = resoursePatternResolver.getResources("file:src/main/resources/input/partitioner/*.csv");
+        } catch (IOException e) {
+            throw new RuntimeException("I/O problems when resolving the input file pattern.", e);
+        }
+        partitioner.setResources(resources);
+        return partitioner;
+    }
+
+    @Bean
+    @StepScope
+    public FlatFileItemReader<Transaction> itemReader(@Value("#{stepExecutionContext[fileName]}") String filename) throws UnexpectedInputException, ParseException {
+        FlatFileItemReader<Transaction> reader = new FlatFileItemReader<Transaction>();
+        DelimitedLineTokenizer tokenizer = new DelimitedLineTokenizer();
+        String[] tokens = { "username", "userid", "transactiondate", "amount" };
+        tokenizer.setNames(tokens);
+        reader.setResource(new ClassPathResource("input/partitioner/" + filename));
+        DefaultLineMapper<Transaction> lineMapper = new DefaultLineMapper<Transaction>();
+        lineMapper.setLineTokenizer(tokenizer);
+        lineMapper.setFieldSetMapper(new RecordFieldSetMapper());
+        reader.setLinesToSkip(1);
+        reader.setLineMapper(lineMapper);
+        return reader;
+    }
+
+    @Bean(destroyMethod = "")
+    @StepScope
+    public StaxEventItemWriter<Transaction> itemWriter(Marshaller marshaller, @Value("#{stepExecutionContext[opFileName]}") String filename) throws MalformedURLException {
+        StaxEventItemWriter<Transaction> itemWriter = new StaxEventItemWriter<>();
+        itemWriter.setMarshaller(marshaller);
+        itemWriter.setRootTagName("transactionRecord");
+        itemWriter.setResource(new FileSystemResource("src/main/resources/output/" + filename));
+        return itemWriter;
+    }
+
+    @Bean
+    public Marshaller marshaller() {
+        Jaxb2Marshaller marshaller = new Jaxb2Marshaller();
+        marshaller.setClassesToBeBound(new Class[] { Transaction.class });
+        return marshaller;
+    }
+
+    @Bean
+    public TaskExecutor taskExecutor() {
+        ThreadPoolTaskExecutor taskExecutor = new ThreadPoolTaskExecutor();
+        taskExecutor.setMaxPoolSize(5);
+        taskExecutor.setCorePoolSize(5);
+        taskExecutor.setQueueCapacity(5);
+        taskExecutor.afterPropertiesSet();
+        return taskExecutor;
+    }
+
+    private JobRepository getJobRepository() throws Exception {
+        JobRepositoryFactoryBean factory = new JobRepositoryFactoryBean();
+        factory.setDataSource(dataSource());
+        factory.setTransactionManager(getTransactionManager());
+        // JobRepositoryFactoryBean's methods Throws Generic Exception,
+        // it would have been better to have a specific one
+        factory.afterPropertiesSet();
+        return (JobRepository) factory.getObject();
+    }
+
+    private DataSource dataSource() {
+        EmbeddedDatabaseBuilder builder = new EmbeddedDatabaseBuilder();
+        EmbeddedDatabase db = builder.setType(EmbeddedDatabaseType.HSQL)
+            .addScript("classpath:org/springframework/batch/core/schema-drop-h2.sql")
+            .addScript("classpath:org/springframework/batch/core/schema-h2.sql")
+            .build();
+        return db;
+    }
+
+    private PlatformTransactionManager getTransactionManager() {
+        return new ResourcelessTransactionManager();
+    }
+
+    public JobLauncher getJobLauncher() throws Exception {
+        SimpleJobLauncher jobLauncher = new SimpleJobLauncher();
+        // SimpleJobLauncher's methods Throws Generic Exception,
+        // it would have been better to have a specific one
+        jobLauncher.setJobRepository(getJobRepository());
+        jobLauncher.afterPropertiesSet();
+        return jobLauncher;
+    }
+}

spring-batch/src/main/java/org/baeldung/spring_batch_intro/partitioner/SpringbatchPartitionerApp.java

@@ -0,0 +1,28 @@
+package org.baeldung.spring_batch_intro.partitioner;
+
+import org.springframework.batch.core.Job;
+import org.springframework.batch.core.JobExecution;
+import org.springframework.batch.core.JobParameters;
+import org.springframework.batch.core.launch.JobLauncher;
+import org.springframework.context.annotation.AnnotationConfigApplicationContext;
+
+public class SpringbatchPartitionerApp {
+    public static void main(final String[] args) {
+        // Spring Java config
+        final AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
+        context.register(SpringbatchPartitionConfig.class);
+        context.refresh();
+
+        final JobLauncher jobLauncher = (JobLauncher) context.getBean("jobLauncher");
+        final Job job = (Job) context.getBean("partitionerJob");
+        System.out.println("Starting the batch job");
+        try {
+            final JobExecution execution = jobLauncher.run(job, new JobParameters());
+            System.out.println("Job Status : " + execution.getStatus());
+            System.out.println("Job succeeded");
+        } catch (final Exception e) {
+            e.printStackTrace();
+            System.out.println("Job failed");
+        }
+    }
+}

spring-batch/src/main/resources/input/partitioner/record1.csv

@@ -0,0 +1,4 @@
+username, user_id, transaction_date, transaction_amount
+devendra, 1234, 31/10/2015, 10000
+john, 2134, 3/12/2015, 12321
+robin, 2134, 2/02/2015, 23411

spring-batch/src/main/resources/input/partitioner/record2.csv

@@ -0,0 +1,4 @@
+username, user_id, transaction_date, transaction_amount
+devendra, 1234, 31/10/2015, 10000
+john, 2134, 3/12/2015, 12321
+robin, 2134, 2/02/2015, 23411

spring-batch/src/main/resources/input/partitioner/record3.csv

@@ -0,0 +1,4 @@
+username, user_id, transaction_date, transaction_amount
+devendra, 1234, 31/10/2015, 10000
+john, 2134, 3/12/2015, 12321
+robin, 2134, 2/02/2015, 23411

spring-batch/src/main/resources/input/partitioner/record4.csv

@@ -0,0 +1,4 @@
+username, user_id, transaction_date, transaction_amount
+devendra, 1234, 31/10/2015, 10000
+john, 2134, 3/12/2015, 12321
+robin, 2134, 2/02/2015, 23411

spring-batch/src/main/resources/input/partitioner/record5.csv

@@ -0,0 +1,4 @@
+username, user_id, transaction_date, transaction_amount
+devendra, 1234, 31/10/2015, 10000
+john, 2134, 3/12/2015, 12321
+robin, 2134, 2/02/2015, 23411

spring-batch/src/main/resources/output/output1.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<transactionRecord>
+	<transactionRecord>
+		<amount>10000.0</amount>
+		<transactionDate>2015-10-31T00:00:00+05:30</transactionDate>
+		<userId>1234</userId>
+		<username>devendra</username>
+	</transactionRecord>
+	<transactionRecord>
+		<amount>12321.0</amount>
+		<transactionDate>2015-12-03T00:00:00+05:30</transactionDate>
+		<userId>2134</userId>
+		<username>john</username>
+	</transactionRecord>
+	<transactionRecord>
+		<amount>23411.0</amount>
+		<transactionDate>2015-02-02T00:00:00+05:30</transactionDate>
+		<userId>2134</userId>
+		<username>robin</username>
+	</transactionRecord>
+</transactionRecord>

spring-batch/src/main/resources/output/output2.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<transactionRecord>
+	<transactionRecord>
+		<amount>10000.0</amount>
+		<transactionDate>2015-10-31T00:00:00+05:30</transactionDate>
+		<userId>1234</userId>
+		<username>devendra</username>
+	</transactionRecord>
+	<transactionRecord>
+		<amount>12321.0</amount>
+		<transactionDate>2015-12-03T00:00:00+05:30</transactionDate>
+		<userId>2134</userId>
+		<username>john</username>
+	</transactionRecord>
+	<transactionRecord>
+		<amount>23411.0</amount>
+		<transactionDate>2015-02-02T00:00:00+05:30</transactionDate>
+		<userId>2134</userId>
+		<username>robin</username>
+	</transactionRecord>
+</transactionRecord>

spring-batch/src/main/resources/output/output3.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<transactionRecord>
+	<transactionRecord>
+		<amount>10000.0</amount>
+		<transactionDate>2015-10-31T00:00:00+05:30</transactionDate>
+		<userId>1234</userId>
+		<username>devendra</username>
+	</transactionRecord>
+	<transactionRecord>
+		<amount>12321.0</amount>
+		<transactionDate>2015-12-03T00:00:00+05:30</transactionDate>
+		<userId>2134</userId>
+		<username>john</username>
+	</transactionRecord>
+	<transactionRecord>
+		<amount>23411.0</amount>
+		<transactionDate>2015-02-02T00:00:00+05:30</transactionDate>
+		<userId>2134</userId>
+		<username>robin</username>
+	</transactionRecord>
+</transactionRecord>

spring-batch/src/main/resources/output/output4.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<transactionRecord>
+	<transactionRecord>
+		<amount>10000.0</amount>
+		<transactionDate>2015-10-31T00:00:00+05:30</transactionDate>
+		<userId>1234</userId>
+		<username>devendra</username>
+	</transactionRecord>
+	<transactionRecord>
+		<amount>12321.0</amount>
+		<transactionDate>2015-12-03T00:00:00+05:30</transactionDate>
+		<userId>2134</userId>
+		<username>john</username>
+	</transactionRecord>
+	<transactionRecord>
+		<amount>23411.0</amount>
+		<transactionDate>2015-02-02T00:00:00+05:30</transactionDate>
+		<userId>2134</userId>
+		<username>robin</username>
+	</transactionRecord>
+</transactionRecord>

spring-batch/src/main/resources/output/output5.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<transactionRecord>
+	<transactionRecord>
+		<amount>10000.0</amount>
+		<transactionDate>2015-10-31T00:00:00+05:30</transactionDate>
+		<userId>1234</userId>
+		<username>devendra</username>
+	</transactionRecord>
+	<transactionRecord>
+		<amount>12321.0</amount>
+		<transactionDate>2015-12-03T00:00:00+05:30</transactionDate>
+		<userId>2134</userId>
+		<username>john</username>
+	</transactionRecord>
+	<transactionRecord>
+		<amount>23411.0</amount>
+		<transactionDate>2015-02-02T00:00:00+05:30</transactionDate>
+		<userId>2134</userId>
+		<username>robin</username>
+	</transactionRecord>
+</transactionRecord>

spring-jpa/pom.xml

@@ -102,6 +102,7 @@
 		<dependency>
 			<groupId>javax.servlet</groupId>
 			<artifactId>servlet-api</artifactId>
+            <scope>provided</scope>
 			<version>${javax.servlet.servlet-api.version}</version>
 		</dependency>
 

spring-rest/src/main/java/org/baeldung/web/controller/redirect/RedirectController.java

@@ -1,11 +1,15 @@
 package org.baeldung.web.controller.redirect;
 
+import javax.servlet.http.HttpServletRequest;
+
+import org.springframework.http.HttpStatus;
 import org.springframework.stereotype.Controller;
 import org.springframework.ui.ModelMap;
 import org.springframework.web.bind.annotation.ModelAttribute;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestMethod;
 import org.springframework.web.servlet.ModelAndView;
+import org.springframework.web.servlet.View;
 import org.springframework.web.servlet.mvc.support.RedirectAttributes;
 import org.springframework.web.servlet.view.RedirectView;
 
@@ -49,4 +53,16 @@ public class RedirectController {
         model.addAttribute("redirectionAttribute", flashAttribute);
         return new ModelAndView("redirection", model);
     }
+
+    @RequestMapping(value = "/redirectPostToPost", method = RequestMethod.POST)
+    public ModelAndView redirectPostToPost(HttpServletRequest request) {
+        request.setAttribute(View.RESPONSE_STATUS_ATTRIBUTE, HttpStatus.TEMPORARY_REDIRECT);
+        return new ModelAndView("redirect:/redirectedPostToPost");
+    }
+
+    @RequestMapping(value = "/redirectedPostToPost", method = RequestMethod.POST)
+    public ModelAndView redirectedPostToPost() {
+        return new ModelAndView("redirection");
+    }
+
 }