Merge branch 'eugenp:master' into master

2021-05-17 21:40:12 +03:00
parent 3327bf0268 d1e8164581
commit ab1b876103
213 changed files with 1865 additions and 821 deletions
@@ -45,4 +45,4 @@
        <providermodule.version>1.0</providermodule.version>
    </properties>

-</project>
+</project>
@@ -27,6 +27,17 @@
            <version>${lombok.version}</version>
            <scope>provided</scope>
        </dependency>
+        <dependency>
+            <groupId>org.openjdk.jmh</groupId>
+            <artifactId>jmh-core</artifactId>
+            <version>${jmh.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.openjdk.jmh</groupId>
+            <artifactId>jmh-generator-annprocess</artifactId>
+            <version>${jmh.version}</version>
+            <scope>test</scope>
+        </dependency>
        <!-- test scoped -->
        <dependency>
            <groupId>org.assertj</groupId>
@@ -44,11 +55,30 @@
                <filtering>true</filtering>
            </resource>
        </resources>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>1.8</source>
+                    <target>1.8</target>
+                    <annotationProcessorPaths>
+                        <path>
+                            <groupId>org.openjdk.jmh</groupId>
+                            <artifactId>jmh-generator-annprocess</artifactId>
+                            <version>${jmh.version}</version>
+                        </path>
+                    </annotationProcessorPaths>
+                </configuration>
+            </plugin>
+        </plugins>
    </build>

    <properties>
+        <lombok.version>1.18.20</lombok.version>
        <!-- testing -->
        <assertj.version>3.6.1</assertj.version>
+        <jmh.version>1.29</jmh.version>
    </properties>

 </project>
@@ -0,0 +1,9 @@
+package com.baeldung.streams.parallel;
+
+public class BenchmarkRunner {
+
+    public static void main(String[] args) throws Exception {
+        org.openjdk.jmh.Main.main(args);
+    }
+
+}
@@ -0,0 +1,54 @@
+package com.baeldung.streams.parallel;
+
+import org.openjdk.jmh.annotations.Benchmark;
+import org.openjdk.jmh.annotations.BenchmarkMode;
+import org.openjdk.jmh.annotations.Mode;
+import org.openjdk.jmh.annotations.OutputTimeUnit;
+
+import java.util.ArrayList;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.concurrent.TimeUnit;
+import java.util.stream.IntStream;
+
+public class DifferentSourceSplitting {
+
+    private static final List<Integer> arrayListOfNumbers = new ArrayList<>();
+    private static final List<Integer> linkedListOfNumbers = new LinkedList<>();
+
+    static {
+        IntStream.rangeClosed(1, 1_000_000).forEach(i -> {
+            arrayListOfNumbers.add(i);
+            linkedListOfNumbers.add(i);
+        });
+    }
+
+    @Benchmark
+    @BenchmarkMode(Mode.AverageTime)
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    public static void differentSourceArrayListSequential() {
+        arrayListOfNumbers.stream().reduce(0, Integer::sum);
+    }
+
+    @Benchmark
+    @BenchmarkMode(Mode.AverageTime)
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    public static void differentSourceArrayListParallel() {
+        arrayListOfNumbers.parallelStream().reduce(0, Integer::sum);
+    }
+
+    @Benchmark
+    @BenchmarkMode(Mode.AverageTime)
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    public static void differentSourceLinkedListSequential() {
+        linkedListOfNumbers.stream().reduce(0, Integer::sum);
+    }
+
+    @Benchmark
+    @BenchmarkMode(Mode.AverageTime)
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    public static void differentSourceLinkedListParallel() {
+        linkedListOfNumbers.parallelStream().reduce(0, Integer::sum);
+    }
+
+}
@@ -0,0 +1,52 @@
+package com.baeldung.streams.parallel;
+
+import org.openjdk.jmh.annotations.Benchmark;
+import org.openjdk.jmh.annotations.BenchmarkMode;
+import org.openjdk.jmh.annotations.Mode;
+import org.openjdk.jmh.annotations.OutputTimeUnit;
+
+import java.util.Arrays;
+import java.util.concurrent.TimeUnit;
+import java.util.stream.IntStream;
+
+public class MemoryLocalityCosts {
+
+    private static final int[] intArray = new int[1_000_000];
+    private static final Integer[] integerArray = new Integer[1_000_000];
+
+    static {
+        IntStream.rangeClosed(1, 1_000_000).forEach(i -> {
+            intArray[i-1] = i;
+            integerArray[i-1] = i;
+        });
+    }
+
+    @Benchmark
+    @BenchmarkMode(Mode.AverageTime)
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    public static void localityIntArraySequential() {
+        Arrays.stream(intArray).reduce(0, Integer::sum);
+    }
+
+    @Benchmark
+    @BenchmarkMode(Mode.AverageTime)
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    public static void localityIntArrayParallel() {
+        Arrays.stream(intArray).parallel().reduce(0, Integer::sum);
+    }
+
+    @Benchmark
+    @BenchmarkMode(Mode.AverageTime)
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    public static void localityIntegerArraySequential() {
+        Arrays.stream(integerArray).reduce(0, Integer::sum);
+    }
+
+    @Benchmark
+    @BenchmarkMode(Mode.AverageTime)
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    public static void localityIntegerArrayParallel() {
+        Arrays.stream(integerArray).parallel().reduce(0, Integer::sum);
+    }
+
+}
@@ -0,0 +1,52 @@
+package com.baeldung.streams.parallel;
+
+import org.openjdk.jmh.annotations.Benchmark;
+import org.openjdk.jmh.annotations.BenchmarkMode;
+import org.openjdk.jmh.annotations.Mode;
+import org.openjdk.jmh.annotations.OutputTimeUnit;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.TimeUnit;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+
+public class MergingCosts {
+
+    private static final List<Integer> arrayListOfNumbers = new ArrayList<>();
+
+    static {
+        IntStream.rangeClosed(1, 1_000_000).forEach(i -> {
+            arrayListOfNumbers.add(i);
+        });
+    }
+
+    @Benchmark
+    @BenchmarkMode(Mode.AverageTime)
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    public static void mergingCostsSumSequential() {
+        arrayListOfNumbers.stream().reduce(0, Integer::sum);
+    }
+
+    @Benchmark
+    @BenchmarkMode(Mode.AverageTime)
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    public static void mergingCostsSumParallel() {
+        arrayListOfNumbers.stream().parallel().reduce(0, Integer::sum);
+    }
+
+    @Benchmark
+    @BenchmarkMode(Mode.AverageTime)
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    public static void mergingCostsGroupingSequential() {
+        arrayListOfNumbers.stream().collect(Collectors.toSet());
+    }
+
+    @Benchmark
+    @BenchmarkMode(Mode.AverageTime)
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    public static void mergingCostsGroupingParallel() {
+        arrayListOfNumbers.stream().parallel().collect(Collectors.toSet());
+    }
+
+}
@@ -0,0 +1,15 @@
+package com.baeldung.streams.parallel;
+
+import java.util.Arrays;
+import java.util.List;
+
+public class ParallelStream {
+
+    public static void main(String[] args) {
+        List<Integer> listOfNumbers = Arrays.asList(1, 2, 3, 4);
+        listOfNumbers.parallelStream().forEach(number ->
+          System.out.println(number + " " + Thread.currentThread().getName())
+        );
+    }
+
+}
@@ -0,0 +1,15 @@
+package com.baeldung.streams.parallel;
+
+import java.util.Arrays;
+import java.util.List;
+
+public class SequentialStream {
+
+    public static void main(String[] args) {
+        List<Integer> listOfNumbers = Arrays.asList(1, 2, 3, 4);
+        listOfNumbers.stream().forEach(number ->
+          System.out.println(number + " " + Thread.currentThread().getName())
+        );
+    }
+
+}
@@ -0,0 +1,27 @@
+package com.baeldung.streams.parallel;
+
+import org.openjdk.jmh.annotations.Benchmark;
+import org.openjdk.jmh.annotations.BenchmarkMode;
+import org.openjdk.jmh.annotations.Mode;
+import org.openjdk.jmh.annotations.OutputTimeUnit;
+
+import java.util.concurrent.TimeUnit;
+import java.util.stream.IntStream;
+
+public class SplittingCosts {
+
+    @Benchmark
+    @BenchmarkMode(Mode.AverageTime)
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    public static void sourceSplittingIntStreamSequential() {
+        IntStream.rangeClosed(1, 100).reduce(0, Integer::sum);
+    }
+
+    @Benchmark
+    @BenchmarkMode(Mode.AverageTime)
+    @OutputTimeUnit(TimeUnit.NANOSECONDS)
+    public static void sourceSplittingIntStreamParallel() {
+        IntStream.rangeClosed(1, 100).parallel().reduce(0, Integer::sum);
+    }
+
+}
@@ -0,0 +1,46 @@
+package com.baeldung.streams.parallel;
+
+import org.junit.jupiter.api.Test;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ForkJoinPool;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class ForkJoinUnitTest {
+
+    @Test
+    void givenSequentialStreamOfNumbers_whenReducingSumWithIdentityFive_thenResultIsCorrect() {
+        List<Integer> listOfNumbers = Arrays.asList(1, 2, 3, 4);
+        int sum = listOfNumbers.stream().reduce(5, Integer::sum);
+        assertThat(sum).isEqualTo(15);
+    }
+
+    @Test
+    void givenParallelStreamOfNumbers_whenReducingSumWithIdentityFive_thenResultIsNotCorrect() {
+        List<Integer> listOfNumbers = Arrays.asList(1, 2, 3, 4);
+        int sum = listOfNumbers.parallelStream().reduce(5, Integer::sum);
+        assertThat(sum).isNotEqualTo(15);
+    }
+
+    @Test
+    void givenParallelStreamOfNumbers_whenReducingSumWithIdentityZero_thenResultIsCorrect() {
+        List<Integer> listOfNumbers = Arrays.asList(1, 2, 3, 4);
+        int sum = listOfNumbers.parallelStream().reduce(0, Integer::sum) + 5;
+        assertThat(sum).isEqualTo(15);
+    }
+
+    @Test
+    public void givenParallelStreamOfNumbers_whenUsingCustomThreadPool_thenResultIsCorrect()
+      throws InterruptedException, ExecutionException {
+        List<Integer> listOfNumbers = Arrays.asList(1, 2, 3, 4);
+        ForkJoinPool customThreadPool = new ForkJoinPool(4);
+        int sum = customThreadPool.submit(
+          () -> listOfNumbers.parallelStream().reduce(0, Integer::sum)).get();
+        customThreadPool.shutdown();
+        assertThat(sum).isEqualTo(10);
+    }
+
+}
@@ -0,0 +1,74 @@
+package com.baeldung.stringtobigdecimal;
+
+import static org.junit.Assert.assertEquals;
+
+import java.math.BigDecimal;
+import java.text.DecimalFormat;
+import java.text.DecimalFormatSymbols;
+import java.text.ParseException;
+
+import org.junit.Test;
+
+public class StringToBigDecimalConversionUnitTest {
+
+	@Test
+	public void givenValidString_WhenBigDecimalObjectWithStringParameter_ThenResultIsDecimalObject() {
+		BigDecimal bigDecimal = new BigDecimal(123);
+		assertEquals(bigDecimal, new BigDecimal("123"));
+	}
+
+	@Test(expected = NullPointerException.class)
+	public void givenNullString_WhenBigDecimalObjectWithStringParameter_ThenNullPointerExceptionIsThrown() {
+		String bigDecimal = null;
+		new BigDecimal(bigDecimal);
+	}
+
+	@Test(expected = NumberFormatException.class)
+	public void givenInalidString_WhenBigDecimalObjectWithStringParameter_ThenNumberFormatExceptionIsThrown() {
+		new BigDecimal("&");
+	}
+
+	@Test
+	public void givenValidString_WhenValueOfDoubleFromString_ThenResultIsDecimalObject() {
+		BigDecimal bigDecimal = new BigDecimal(123.42).setScale(2, BigDecimal.ROUND_HALF_UP);
+		assertEquals(bigDecimal, BigDecimal.valueOf(Double.valueOf("123.42")));
+	}
+
+	@Test(expected = NullPointerException.class)
+	public void givenNullString_WhenValueOfDoubleFromString_ThenNullPointerExceptionIsThrown() {
+		BigDecimal.valueOf(Double.valueOf(null));
+	}
+
+	@Test(expected = NumberFormatException.class)
+	public void givenInalidString_WhenValueOfDoubleFromString_ThenNumberFormatExceptionIsThrown() {
+		BigDecimal.valueOf(Double.valueOf("&"));
+	}
+
+	@Test
+	public void givenValidString_WhenDecimalFormatOfString_ThenResultIsDecimalObject() throws ParseException {
+		BigDecimal bigDecimal = new BigDecimal(10692467440017.111).setScale(3, BigDecimal.ROUND_HALF_UP);
+
+		DecimalFormatSymbols symbols = new DecimalFormatSymbols();
+		symbols.setGroupingSeparator(',');
+		symbols.setDecimalSeparator('.');
+		String pattern = "#,##0.0#";
+		DecimalFormat decimalFormat = new DecimalFormat(pattern, symbols);
+		decimalFormat.setParseBigDecimal(true);
+
+		// parse the string value
+		BigDecimal parsedStringValue = (BigDecimal) decimalFormat.parse("10,692,467,440,017.111");
+
+		assertEquals(bigDecimal, parsedStringValue);
+	}
+
+	@Test(expected = NullPointerException.class)
+	public void givenNullString_WhenDecimalFormatOfString_ThenNullPointerExceptionIsThrown() throws ParseException {
+		new DecimalFormat("#").parse(null);
+	}
+
+	@Test(expected = ParseException.class)
+	public void givenInalidString_WhenDecimalFormatOfString_ThenNumberFormatExceptionIsThrown() throws ParseException {
+		new DecimalFormat("#").parse("&");
+	}
+
+}
@@ -0,0 +1,59 @@
+package com.baeldung.splitkeepdelimiters;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.util.regex.Pattern;
+
+import org.apache.commons.lang3.StringUtils;
+import org.junit.jupiter.api.Test;
+
+import com.google.common.base.Splitter;
+
+public class SplitAndKeepDelimitersUnitTest {
+
+    private final String positivelookAheadRegex = "((?=@))";
+    private final String positivelookBehindRegex = "((?<=@))";
+    private final String positivelookAroundRegex = "((?=@)|(?<=@))";
+    private final String positiveLookAroundMultiDelimiterRegex = "((?=:|#|@)|(?<=:|#|@))";
+
+    private String text = "Hello@World@This@Is@A@Java@Program";
+    private String textMixed = "@HelloWorld@This:Is@A#Java#Program";
+    private String textMixed2 = "pg@no;10@hello;world@this;is@a#10words;Java#Program";
+
+    @Test
+    public void givenString_splitAndKeepDelimiters_using_javaLangString() {
+
+        assertThat(text.split(positivelookAheadRegex)).containsExactly("Hello", "@World", "@This", "@Is", "@A", "@Java", "@Program");
+
+        assertThat(text.split(positivelookBehindRegex)).containsExactly("Hello@", "World@", "This@", "Is@", "A@", "Java@", "Program");
+
+        assertThat(text.split(positivelookAroundRegex)).containsExactly("Hello", "@", "World", "@", "This", "@", "Is", "@", "A", "@", "Java", "@", "Program");
+
+        assertThat(textMixed.split(positiveLookAroundMultiDelimiterRegex)).containsExactly("@", "HelloWorld", "@", "This", ":", "Is", "@", "A", "#", "Java", "#", "Program");
+
+    }
+
+    @Test
+    public void givenString_splitAndKeepDelimiters_using_ApacheCommonsLang3StringUtils() {
+
+        assertThat(StringUtils.splitByCharacterType(textMixed2)).containsExactly("pg", "@", "no", ";", "10", "@", "hello", ";", "world", "@", "this", ";", "is", "@", "a", "#", "10", "words", ";", "J", "ava", "#", "P", "rogram");
+
+    }
+
+    @Test
+    public void givenString_splitAndKeepDelimiters_using_GuavaSplitter() {
+
+        assertThat(Splitter.onPattern(positivelookAroundRegex)
+            .splitToList(text)).containsExactly("Hello", "@", "World", "@", "This", "@", "Is", "@", "A", "@", "Java", "@", "Program");
+
+        assertThat(Splitter.on(Pattern.compile(positivelookAroundRegex))
+            .splitToList(text)).containsExactly("Hello", "@", "World", "@", "This", "@", "Is", "@", "A", "@", "Java", "@", "Program");
+
+        assertThat(Splitter.onPattern(positiveLookAroundMultiDelimiterRegex)
+            .splitToList(textMixed)).containsExactly("@", "HelloWorld", "@", "This", ":", "Is", "@", "A", "#", "Java", "#", "Program");
+
+        assertThat(Splitter.on(Pattern.compile(positiveLookAroundMultiDelimiterRegex))
+            .splitToList(textMixed)).containsExactly("@", "HelloWorld", "@", "This", ":", "Is", "@", "A", "#", "Java", "#", "Program");
+
+    }
+}
@@ -19,7 +19,6 @@
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
-            <version>2.1.3.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>io.mantisrx</groupId>
@@ -35,36 +34,31 @@
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
-            <version>2.10.2</version>
        </dependency>
        <dependency>
            <groupId>net.andreinc.mockneat</groupId>
            <artifactId>mockneat</artifactId>
-            <version>0.3.8</version>
+            <version>0.4.2</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
-            <version>1.18.12</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webflux</artifactId>
-            <version>5.0.9.RELEASE</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>io.projectreactor.netty</groupId>
            <artifactId>reactor-netty</artifactId>
-            <version>0.9.12.RELEASE</version>
            <scope>test</scope>
        </dependency>
    </dependencies>
-
    <repositories>
        <repository>
-            <id>SpringLibReleaseRepo</id>
-            <url>https://repo.spring.io/libs-release/</url>
+        	<id>jcenter</id>
+            <url>https://jcenter.bintray.com/</url>
        </repository>
    </repositories>

@@ -26,6 +26,11 @@
            <version>${lombok.version}</version>
            <scope>provided</scope>
        </dependency>
+        <dependency>
+            <groupId>com.google.code.findbugs</groupId>
+            <artifactId>annotations</artifactId>
+            <version>${findbugs.annotations.version}</version>
+        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
@@ -41,6 +46,7 @@

    <properties>
        <intellij.annotations.version>16.0.2</intellij.annotations.version>
+        <findbugs.annotations.version>3.0.1</findbugs.annotations.version>
        <assertj-core.version>3.9.1</assertj-core.version>
    </properties>

@@ -1,12 +1,12 @@
 package com.baeldung.nulls;

-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;

+import edu.umd.cs.findbugs.annotations.NonNull;
+import edu.umd.cs.findbugs.annotations.Nullable;

 public class FindBugsAnnotations {

-    public void accept(@NotNull Object param) {
+    public void accept(@NonNull Object param) {
        System.out.println(param.toString());
    }

@@ -14,7 +14,7 @@ public class FindBugsAnnotations {
        System.out.println("Printing " + param);
    }

-    @NotNull
+    @NonNull
    public Object process() throws Exception {
        Object result = doSomething();
        if (result == null) {
@@ -68,6 +68,12 @@
            <version>${assertj.version}</version>
            <scope>test</scope>
        </dependency>
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>${junit.version}</version>
+            <scope>test</scope>
+        </dependency>
    </dependencies>

    <build>
@@ -0,0 +1,41 @@
+package com.baeldung.jpa.IdGeneration;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+
+@Entity
+public class User {
+
+    @Id
+//    @GeneratedValue(strategy = GenerationType.SEQUENCE)
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private long id;
+    private String username;
+    private String password;
+
+    public long getId() {
+        return id;
+    }
+
+    public void setId(long id) {
+        this.id = id;
+    }
+
+    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;
+    }
+}
@@ -0,0 +1,19 @@
+package com.baeldung.jpa.IdGeneration;
+
+import javax.persistence.EntityManager;
+import javax.transaction.Transactional;
+
+public class UserService {
+
+    EntityManager entityManager;
+
+    public UserService(EntityManager entityManager) {
+        this.entityManager = entityManager;
+    }
+
+    @Transactional
+    public long saveUser(User user){
+        entityManager.persist(user);
+        return user.getId();
+    }
+}
@@ -97,4 +97,20 @@
            <property name="hibernate.temp.use_jdbc_metadata_defaults" value="false"/>
        </properties>
    </persistence-unit>
+
+    <persistence-unit name="jpa-h2-id-generation">
+        <provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
+        <class>com.baeldung.jpa.IdGeneration.User</class>
+        <exclude-unlisted-classes>true</exclude-unlisted-classes>
+        <properties>
+            <property name="javax.persistence.jdbc.driver" value="org.h2.Driver"/>
+            <property name="javax.persistence.jdbc.url" value="jdbc:h2:mem:idGen"/>
+            <property name="javax.persistence.jdbc.user" value="sa"/>
+            <property name="javax.persistence.jdbc.password" value=""/>
+            <property name="hibernate.dialect" value="org.hibernate.dialect.H2Dialect"/>
+            <property name="hibernate.hbm2ddl.auto" value="create-drop"/>
+            <property name="hibernate.format_sql" value="true"/>
+            <property name="hibernate.temp.use_jdbc_metadata_defaults" value="false"/>
+        </properties>
+    </persistence-unit>
 </persistence>
@@ -0,0 +1,47 @@
+package com.baeldung.jpa.IdGeneration;
+
+import org.junit.Assert;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import javax.persistence.EntityManager;
+import javax.persistence.EntityManagerFactory;
+import javax.persistence.Persistence;
+import java.util.UUID;
+
+public class IdGenerationIntegrationTest {
+
+    private static EntityManager entityManager;
+    private static UserService service;
+
+    @BeforeClass
+    public static void setup() {
+        EntityManagerFactory factory = Persistence.createEntityManagerFactory("jpa-h2-id-generation");
+        entityManager = factory.createEntityManager();
+        service = new UserService(entityManager);
+    }
+
+    @Test
+    public void whenNewUserIsPersisted_thenEntityHasNoId() {
+        User user = new User();
+        user.setUsername("test");
+        user.setPassword(UUID.randomUUID().toString());
+
+        long index = service.saveUser(user);
+        Assert.assertEquals(0L, index);
+    }
+
+    @Test
+    public void whenTransactionIsControlled_thenEntityHasId() {
+        User user = new User();
+        user.setUsername("test");
+        user.setPassword(UUID.randomUUID().toString());
+
+        entityManager.getTransaction().begin();
+        long index = service.saveUser(user);
+        entityManager.getTransaction().commit();
+
+        Assert.assertEquals(2L, index);
+    }
+
+}
@@ -0,0 +1,25 @@
+package com.baeldung.attribute.override.entity;
+
+import javax.persistence.Embeddable;
+
+@Embeddable
+public class Address {
+    private String name;
+    private String city;
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getCity() {
+        return city;
+    }
+
+    public void setCity(String city) {
+        this.city = city;
+    }
+}
@@ -0,0 +1,29 @@
+package com.baeldung.attribute.override.entity;
+
+import javax.persistence.Embeddable;
+import javax.persistence.Embedded;
+import java.time.LocalDate;
+
+@Embeddable
+public class Brand {
+    private String name;
+    private LocalDate foundationDate;
+    @Embedded
+    private Address address;
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public LocalDate getFoundationDate() {
+        return foundationDate;
+    }
+
+    public void setFoundationDate(LocalDate foundationDate) {
+        this.foundationDate = foundationDate;
+    }
+}
@@ -0,0 +1,54 @@
+package com.baeldung.attribute.override.entity;
+
+import javax.persistence.AttributeOverride;
+import javax.persistence.AttributeOverrides;
+import javax.persistence.Column;
+import javax.persistence.ElementCollection;
+import javax.persistence.Embedded;
+import javax.persistence.Entity;
+import java.util.Map;
+
+@Entity
+@AttributeOverride(name = "identifier", column = @Column(name = "VIN"))
+public class Car extends Vehicle {
+
+    private String model;
+    private String name;
+    @Embedded
+    @AttributeOverrides({
+      @AttributeOverride(name = "name", column = @Column(name = "BRAND_NAME", length = 5)),
+      @AttributeOverride(name = "address.name", column = @Column(name = "ADDRESS_NAME"))
+    })
+    private Brand brand;
+    @ElementCollection
+    @AttributeOverrides({
+      @AttributeOverride(name = "key.name", column = @Column(name = "OWNER_NAME")),
+      @AttributeOverride(name = "key.surname", column = @Column(name = "OWNER_SURNAME")),
+      @AttributeOverride(name = "value.name", column = @Column(name = "ADDRESS_NAME")),
+    })
+    Map<Owner, Address> owners;
+
+    public String getModel() {
+        return model;
+    }
+
+    public void setModel(String model) {
+        this.model = model;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public Brand getBrand() {
+        return brand;
+    }
+
+    public void setBrand(Brand brand) {
+        this.brand = brand;
+    }
+}
@@ -0,0 +1,25 @@
+package com.baeldung.attribute.override.entity;
+
+import javax.persistence.Embeddable;
+
+@Embeddable
+public class Owner {
+    private String name;
+    private String surname;
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getSurname() {
+        return surname;
+    }
+
+    public void setSurname(String surname) {
+        this.surname = surname;
+    }
+}
@@ -0,0 +1,38 @@
+package com.baeldung.attribute.override.entity;
+
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import javax.persistence.MappedSuperclass;
+
+@MappedSuperclass
+public class Vehicle {
+    @Id
+    @GeneratedValue
+    private Integer id;
+    private String identifier;
+    private Integer numberOfWheels;
+
+    public Integer getId() {
+        return id;
+    }
+
+    public void setId(Integer id) {
+        this.id = id;
+    }
+
+    public String getIdentifier() {
+        return identifier;
+    }
+
+    public void setIdentifier(String identifier) {
+        this.identifier = identifier;
+    }
+
+    public Integer getNumberOfWheels() {
+        return numberOfWheels;
+    }
+
+    public void setNumberOfWheels(Integer numberOfWheels) {
+        this.numberOfWheels = numberOfWheels;
+    }
+}
@@ -0,0 +1,7 @@
+package com.baeldung.attribute.override.repository;
+
+import com.baeldung.attribute.override.entity.Car;
+import org.springframework.data.jpa.repository.JpaRepository;
+
+public interface CarRepository extends JpaRepository<Car, Integer> {
+}
@@ -0,0 +1,56 @@
+package com.baeldung.attribute.override;
+
+import com.baeldung.Application;
+import com.baeldung.attribute.override.entity.Address;
+import com.baeldung.attribute.override.entity.Brand;
+import com.baeldung.attribute.override.entity.Car;
+import com.baeldung.attribute.override.repository.CarRepository;
+import org.assertj.core.api.Assertions;
+import org.jetbrains.annotations.NotNull;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.time.LocalDate;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest(classes = { Application.class })
+public class AttributeOverrideIntegrationTest {
+
+    private static final LocalDate FORD_FOUNDATION_DATE = LocalDate.parse("1903-06-16");
+    @Autowired
+    CarRepository carRepository;
+
+    @Test
+    @Transactional
+    public void whenInsertingCar_thenEmbeddedAndMappedFieldsArePopulated() {
+
+        Car fordMustang = createMustang();
+
+        carRepository.save(fordMustang);
+        Car actualCar = carRepository.getOne(fordMustang.getId());
+
+        Assertions.assertThat(actualCar).isEqualTo(fordMustang);
+    }
+
+    @NotNull
+    private Car createMustang() {
+        Address address = new Address();
+        address.setName("Ford United States");
+        address.setCity("Dearborn");
+
+        Brand ford = new Brand();
+        ford.setName("Ford");
+        ford.setFoundationDate(FORD_FOUNDATION_DATE);
+
+        Car fordMustang = new Car();
+        fordMustang.setIdentifier("WP1AB29P88LA47599");
+        fordMustang.setModel("Ford");
+        fordMustang.setName("My car");
+        fordMustang.setBrand(ford);
+        return fordMustang;
+    }
+}
@@ -0,0 +1,68 @@
+package com.baeldung.softdelete;
+
+
+import java.io.Serializable;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.Table;
+
+import org.hibernate.annotations.Filter;
+import org.hibernate.annotations.FilterDef;
+import org.hibernate.annotations.ParamDef;
+import org.hibernate.annotations.SQLDelete;
+
+@Entity
+@Table(name = "tbl_products")
+@SQLDelete(sql = "UPDATE tbl_products SET deleted = true WHERE id=?")
+@FilterDef(name = "deletedProductFilter", parameters = @ParamDef(name = "isDeleted", type = "boolean"))
+@Filter(name = "deletedProductFilter", condition = "deleted = :isDeleted")
+public class Product implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    private String name;
+
+    private double price;
+
+    private boolean deleted = Boolean.FALSE;
+
+    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 double getPrice() {
+        return price;
+    }
+
+    public void setPrice(double price) {
+        this.price = price;
+    }
+
+    public boolean isDeleted() {
+        return deleted;
+    }
+
+    public void setDeleted(boolean deleted) {
+        this.deleted = deleted;
+    }
+
+}
@@ -0,0 +1,34 @@
+package com.baeldung.softdelete;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.web.bind.annotation.DeleteMapping;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+@RequestMapping("/api/products")
+public class ProductController {
+
+    @Autowired
+    private ProductService productService;
+
+    @PostMapping
+    public Product createOne(@RequestBody Product product) {
+        return productService.create(product);
+    }
+
+    @DeleteMapping("/{id}")
+    public void removeOne(@PathVariable("id") Long id) {
+        productService.remove(id);
+    }
+
+    @GetMapping
+    public Iterable<Product> findAll(@RequestParam(value = "isDeleted", required = false, defaultValue = "false") boolean isDeleted) {
+        return productService.findAll(isDeleted);
+    }
+}
@@ -0,0 +1,7 @@
+package com.baeldung.softdelete;
+
+import org.springframework.data.repository.CrudRepository;
+
+public interface ProductRepository extends CrudRepository<Product, Long>{
+
+}
--- a/Show More
+++ b/Show More