Samples for the Intro to QueryDSL article, merged with existing querydsl module. Updated module dependencies. (#476)

querydsl/pom.xml

@@ -14,30 +14,25 @@
 
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-        <java.version>1.6</java.version>
+        <java.version>1.8</java.version>
-        <junit.version>4.10</junit.version>
+        <junit.version>4.12</junit.version>
-        <spring.version>3.1.0.RELEASE</spring.version>
+        <spring.version>4.3.1.RELEASE</spring.version>
-        <hibernate.version>4.3.11.Final</hibernate.version>
+        <hibernate.version>5.2.1.Final</hibernate.version>
-        <querydsl.version>2.5.0</querydsl.version>
+        <querydsl.version>4.1.3</querydsl.version>
-        <slf4j.version>1.5.10</slf4j.version>
+        <slf4j.version>1.7.21</slf4j.version>
     </properties>
 
     <dependencies>
         <!-- QueryDSL -->
-        <dependency>
-            <groupId>com.mysema.querydsl</groupId>
-            <artifactId>querydsl-core</artifactId>
-            <version>${querydsl.version}</version>
-        </dependency>
 
         <dependency>
-            <groupId>com.mysema.querydsl</groupId>
+            <groupId>com.querydsl</groupId>
             <artifactId>querydsl-jpa</artifactId>
             <version>${querydsl.version}</version>
         </dependency>
 
         <dependency>
-            <groupId>com.mysema.querydsl</groupId>
+            <groupId>com.querydsl</groupId>
             <artifactId>querydsl-apt</artifactId>
             <version>${querydsl.version}</version>
             <scope>provided</scope>
@@ -53,7 +48,7 @@
 
         <dependency>
             <groupId>org.hibernate.javax.persistence</groupId>
-            <artifactId>hibernate-jpa-2.0-api</artifactId>
+            <artifactId>hibernate-jpa-2.1-api</artifactId>
             <version>1.0.0.Final</version>
             <scope>compile</scope>
         </dependency>
@@ -69,7 +64,7 @@
         <dependency>
             <groupId>commons-pool</groupId>
             <artifactId>commons-pool</artifactId>
-            <version>1.5.5</version>
+            <version>1.6</version>
             <type>jar</type>
             <scope>compile</scope>
         </dependency>
@@ -77,8 +72,8 @@
         <!-- HSQLDB Dependencies -->
         <dependency>
             <groupId>org.hsqldb</groupId>
-            <artifactId>hsqldb-j5</artifactId>
+            <artifactId>hsqldb</artifactId>
-            <version>2.2.4</version>
+            <version>2.3.4</version>
         </dependency>
 
         <!-- Spring Dependencies -->
@@ -118,9 +113,9 @@
 
         <!-- Logging -->
         <dependency>
-            <groupId>org.slf4j</groupId>
+            <groupId>ch.qos.logback</groupId>
-            <artifactId>slf4j-api</artifactId>
+            <artifactId>logback-classic</artifactId>
-            <version>${slf4j.version}</version>
+            <version>1.1.7</version>
         </dependency>
         <dependency>
             <groupId>org.slf4j</groupId>
@@ -128,17 +123,6 @@
             <version>${slf4j.version}</version>
             <scope>runtime</scope>
         </dependency>
-        <dependency>
-            <groupId>org.slf4j</groupId>
-            <artifactId>slf4j-log4j12</artifactId>
-            <version>${slf4j.version}</version>
-            <scope>runtime</scope>
-        </dependency>
-        <dependency>
-            <groupId>log4j</groupId>
-            <artifactId>log4j</artifactId>
-            <version>1.2.16</version>
-        </dependency>
 
         <!-- Test Dependencies -->
         <dependency>
@@ -157,7 +141,7 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
-                <version>2.3.2</version>
+                <version>3.5.1</version>
                 <configuration>
                     <source>${java.version}</source>
                     <target>${java.version}</target>
@@ -168,16 +152,16 @@
             <!-- QueryDSL plugin -->
             <plugin>
                 <groupId>com.mysema.maven</groupId>
-                <artifactId>maven-apt-plugin</artifactId>
+                <artifactId>apt-maven-plugin</artifactId>
-                <version>1.0.3</version>
+                <version>1.1.3</version>
                 <executions>
                     <execution>
                         <goals>
                             <goal>process</goal>
                         </goals>
                         <configuration>
-                            <outputDirectory>target/metamodel</outputDirectory>
+                            <outputDirectory>target/generated-sources/java</outputDirectory>
-                            <processor>com.mysema.query.apt.jpa.JPAAnnotationProcessor</processor>
+                            <processor>com.querydsl.apt.jpa.JPAAnnotationProcessor</processor>
                         </configuration>
                     </execution>
                 </executions>

querydsl/src/main/java/org/baeldung/dao/PersonDaoImpl.java

@@ -10,8 +10,8 @@ import org.baeldung.entity.Person;
 import org.baeldung.entity.QPerson;
 import org.springframework.stereotype.Repository;
 
-import com.mysema.query.group.GroupBy;
+import com.querydsl.core.group.GroupBy;
-import com.mysema.query.jpa.impl.JPAQuery;
+import com.querydsl.jpa.impl.JPAQuery;
 
 @Repository
 public class PersonDaoImpl implements PersonDao {
@@ -27,39 +27,39 @@ public class PersonDaoImpl implements PersonDao {
 
     @Override
     public List<Person> findPersonsByFirstnameQueryDSL(final String firstname) {
-        final JPAQuery query = new JPAQuery(em);
+        final JPAQuery<Person> query = new JPAQuery<>(em);
         final QPerson person = QPerson.person;
 
-        return query.from(person).where(person.firstname.eq(firstname)).list(person);
+        return query.from(person).where(person.firstname.eq(firstname)).fetch();
     }
 
     @Override
     public List<Person> findPersonsByFirstnameAndSurnameQueryDSL(final String firstname, final String surname) {
-        final JPAQuery query = new JPAQuery(em);
+        final JPAQuery<Person> query = new JPAQuery<>(em);
         final QPerson person = QPerson.person;
 
-        return query.from(person).where(person.firstname.eq(firstname).and(person.surname.eq(surname))).list(person);
+        return query.from(person).where(person.firstname.eq(firstname).and(person.surname.eq(surname))).fetch();
     }
 
     @Override
     public List<Person> findPersonsByFirstnameInDescendingOrderQueryDSL(final String firstname) {
-        final JPAQuery query = new JPAQuery(em);
+        final JPAQuery<Person> query = new JPAQuery<>(em);
         final QPerson person = QPerson.person;
 
-        return query.from(person).where(person.firstname.eq(firstname)).orderBy(person.surname.desc()).list(person);
+        return query.from(person).where(person.firstname.eq(firstname)).orderBy(person.surname.desc()).fetch();
     }
 
     @Override
     public int findMaxAge() {
-        final JPAQuery query = new JPAQuery(em);
+        final JPAQuery<Person> query = new JPAQuery<>(em);
         final QPerson person = QPerson.person;
 
-        return query.from(person).list(person.age.max()).get(0);
+        return query.from(person).select(person.age.max()).fetchFirst();
     }
 
     @Override
     public Map<String, Integer> findMaxAgeByName() {
-        final JPAQuery query = new JPAQuery(em);
+        final JPAQuery<Person> query = new JPAQuery<>(em);
         final QPerson person = QPerson.person;
 
         return query.from(person).transform(GroupBy.groupBy(person.firstname).as(GroupBy.max(person.age)));

querydsl/src/main/java/org/baeldung/querydsl/intro/entities/BlogPost.java

@@ -0,0 +1,56 @@
+/*
+ * (c) Центр ИТ, 2016. Все права защищены.
+ */
+package org.baeldung.querydsl.intro.entities;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import javax.persistence.ManyToOne;
+
+@Entity
+public class BlogPost {
+
+    @Id
+    @GeneratedValue
+    private Long id;
+
+    private String title;
+
+    private String body;
+
+    @ManyToOne
+    private User user;
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public void setTitle(String code) {
+        this.title = code;
+    }
+
+    public String getBody() {
+        return body;
+    }
+
+    public void setBody(String body) {
+        this.body = body;
+    }
+
+    public User getUser() {
+        return user;
+    }
+
+    public void setUser(User user) {
+        this.user = user;
+    }
+}

querydsl/src/main/java/org/baeldung/querydsl/intro/entities/User.java

@@ -0,0 +1,55 @@
+/*
+ * (c) Центр ИТ, 2016. Все права защищены.
+ */
+package org.baeldung.querydsl.intro.entities;
+
+import java.util.HashSet;
+import java.util.Set;
+import javax.persistence.*;
+
+@Entity
+public class User {
+
+    @Id
+    @GeneratedValue
+    private Long id;
+
+    private String login;
+
+    private Boolean disabled;
+
+    @OneToMany(cascade = CascadeType.PERSIST, mappedBy = "user")
+    private Set<BlogPost> blogPosts = new HashSet<>(0);
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getLogin() {
+        return login;
+    }
+
+    public void setLogin(String name) {
+        this.login = name;
+    }
+
+    public Set<BlogPost> getBlogPosts() {
+        return blogPosts;
+    }
+
+    public void setBlogPosts(Set<BlogPost> blogPosts) {
+        this.blogPosts = blogPosts;
+    }
+
+    public Boolean getDisabled() {
+        return disabled;
+    }
+
+    public void setDisabled(Boolean disabled) {
+        this.disabled = disabled;
+    }
+}

querydsl/src/main/resources/META-INF/persistence.xml

@@ -16,4 +16,17 @@
         </properties>
     </persistence-unit>
 
+    <!-- PersistenceUnit for Intro to QueryDSL -->
+    <persistence-unit name="org.baeldung.querydsl.intro">
+        <provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
+        <properties>
+            <property name="hibernate.connection.driver_class" value="org.hsqldb.jdbcDriver"/>
+            <property name="hibernate.connection.url" value="jdbc:hsqldb:mem:test"/>
+            <property name="hibernate.connection.username" value="sa"/>
+            <property name="hibernate.connection.password" value=""/>
+            <property name="hibernate.hbm2ddl.auto" value="update"/>
+            <property name="hibernate.dialect" value="org.hibernate.dialect.HSQLDialect" />
+        </properties>
+    </persistence-unit>
+
 </persistence>

querydsl/src/main/resources/logback.xml

@@ -1,12 +1,9 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<!DOCTYPE log4j:configuration SYSTEM "log4j.dtd" >
+<configuration>
-<log4j:configuration xmlns:log4j="http://jakarta.apache.org/log4j/">
 
-    <!-- Appenders -->
+    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
-    <appender name="console" class="org.apache.log4j.ConsoleAppender">
+        <layout class="ch.qos.logback.classic.PatternLayout">
-        <param name="Target" value="System.out" />
+            <Pattern>%d{yyyy-MM-dd HH:mm:ss} [%t] %-5p: %c - %m%n</Pattern>
-        <layout class="org.apache.log4j.PatternLayout">
-            <param name="ConversionPattern" value="%d{yyyy-MM-dd HH:mm:ss} [%t] %-5p: %c - %m%n" />
         </layout>
     </appender>
 
@@ -33,10 +30,8 @@
         <level value="warn" />
     </logger>
 
-    <!-- Root Logger -->
+    <root level="warn">
-    <root>
+        <appender-ref ref="STDOUT"/>
-        <priority value="warn" />
-        <appender-ref ref="console" />
     </root>
 
-</log4j:configuration>
+</configuration>

querydsl/src/test/java/org/baeldung/querydsl/intro/QueryDSLTest.java

@@ -0,0 +1,215 @@
+/*
+ * (c) Центр ИТ, 2016. Все права защищены.
+ */
+package org.baeldung.querydsl.intro;
+
+import java.util.List;
+import javax.persistence.EntityManager;
+import javax.persistence.EntityManagerFactory;
+import javax.persistence.Persistence;
+
+import org.baeldung.querydsl.intro.entities.BlogPost;
+import org.baeldung.querydsl.intro.entities.QBlogPost;
+import org.baeldung.querydsl.intro.entities.QUser;
+import org.baeldung.querydsl.intro.entities.User;
+import com.querydsl.core.Tuple;
+import com.querydsl.core.types.dsl.Expressions;
+import com.querydsl.core.types.dsl.NumberPath;
+import com.querydsl.jpa.JPAExpressions;
+import com.querydsl.jpa.impl.JPAQueryFactory;
+import org.junit.*;
+
+import static org.junit.Assert.*;
+
+public class QueryDSLTest {
+
+    private static EntityManagerFactory emf;
+
+    private EntityManager em;
+
+    private JPAQueryFactory queryFactory;
+
+    @BeforeClass
+    public static void populateDatabase() {
+        emf = Persistence.createEntityManagerFactory("org.baeldung.querydsl.intro");
+        EntityManager em = emf.createEntityManager();
+
+        em.getTransaction().begin();
+        User user1 = new User();
+        user1.setLogin("David");
+        em.persist(user1);
+
+        User user2 = new User();
+        user2.setLogin("Ash");
+        em.persist(user2);
+
+        User user3 = new User();
+        user3.setLogin("Call");
+        em.persist(user3);
+
+        User user4 = new User();
+        user4.setLogin("Bishop");
+        em.persist(user4);
+
+        BlogPost blogPost1 = new BlogPost();
+        blogPost1.setTitle("Hello World!");
+        blogPost1.setUser(user1);
+        em.persist(blogPost1);
+
+        BlogPost blogPost2 = new BlogPost();
+        blogPost2.setTitle("My Second Post");
+        blogPost2.setUser(user1);
+        em.persist(blogPost2);
+
+        BlogPost blogPost3 = new BlogPost();
+        blogPost3.setTitle("Hello World!");
+        blogPost3.setUser(user3);
+        em.persist(blogPost3);
+
+        em.getTransaction().commit();
+
+        em.close();
+
+    }
+
+    @Before
+    public void setUp() {
+        em = emf.createEntityManager();
+        em.getTransaction().begin();
+        queryFactory = new JPAQueryFactory(em);
+    }
+
+    @Test
+    public void whenFindByLogin_thenShouldReturnUser() {
+
+        QUser user = QUser.user;
+        User aUser = queryFactory.selectFrom(user)
+                .where(user.login.eq("David"))
+                .fetchOne();
+
+        assertNotNull(aUser);
+        assertEquals(aUser.getLogin(), "David");
+
+    }
+
+    @Test
+    public void whenUsingOrderBy_thenResultsShouldBeOrdered() {
+
+        QUser user = QUser.user;
+        List<User> users = queryFactory.selectFrom(user)
+                .orderBy(user.login.asc())
+                .fetch();
+
+        assertEquals(users.size(), 4);
+        assertEquals(users.get(0).getLogin(), "Ash");
+        assertEquals(users.get(1).getLogin(), "Bishop");
+        assertEquals(users.get(2).getLogin(), "Call");
+        assertEquals(users.get(3).getLogin(), "David");
+
+    }
+
+    @Test
+    public void whenGroupingByTitle_thenReturnsTuples() {
+
+        QBlogPost blogPost = QBlogPost.blogPost;
+
+        NumberPath<Long> count = Expressions.numberPath(Long.class, "c");
+
+        List<Tuple> userTitleCounts = queryFactory.select(blogPost.title, blogPost.id.count().as(count))
+                .from(blogPost)
+                .groupBy(blogPost.title)
+                .orderBy(count.desc())
+                .fetch();
+
+        assertEquals("Hello World!", userTitleCounts.get(0).get(blogPost.title));
+        assertEquals(new Long(2), userTitleCounts.get(0).get(count));
+
+        assertEquals("My Second Post", userTitleCounts.get(1).get(blogPost.title));
+        assertEquals(new Long(1), userTitleCounts.get(1).get(count));
+
+    }
+
+    @Test
+    public void whenJoiningWithCondition_thenResultCountShouldMatch() {
+
+        QUser user = QUser.user;
+        QBlogPost blogPost = QBlogPost.blogPost;
+
+        List<User> users = queryFactory.selectFrom(user)
+                .innerJoin(user.blogPosts, blogPost)
+                .on(blogPost.title.eq("Hello World!"))
+                .fetch();
+
+        assertEquals(2, users.size());
+    }
+
+    @Test
+    public void whenRefiningWithSubquery_thenResultCountShouldMatch() {
+
+        QUser user = QUser.user;
+        QBlogPost blogPost = QBlogPost.blogPost;
+
+        List<User> users = queryFactory.selectFrom(user)
+                .where(user.id.in(
+                        JPAExpressions.select(blogPost.user.id)
+                                .from(blogPost)
+                                .where(blogPost.title.eq("Hello World!"))))
+                .fetch();
+
+        assertEquals(2, users.size());
+    }
+
+    @Test
+    public void whenUpdating_thenTheRecordShouldChange() {
+
+        QUser user = QUser.user;
+
+        queryFactory.update(user)
+                .where(user.login.eq("Ash"))
+                .set(user.login, "Ash2")
+                .set(user.disabled, true)
+                .execute();
+
+        em.getTransaction().commit();
+
+        em.getTransaction().begin();
+
+        assertEquals(Boolean.TRUE,
+                queryFactory.select(user.disabled)
+                        .from(user)
+                        .where(user.login.eq("Ash2"))
+                        .fetchOne());
+
+    }
+
+    @Test
+    public void whenDeleting_thenTheRecordShouldBeAbsent() {
+
+        QUser user = QUser.user;
+
+        queryFactory.delete(user)
+                .where(user.login.eq("Bishop"))
+                .execute();
+
+        em.getTransaction().commit();
+
+        em.getTransaction().begin();
+
+        assertNull(queryFactory.selectFrom(user)
+                .where(user.login.eq("Bishop"))
+                .fetchOne());
+
+    }
+
+    @After
+    public void tearDown() {
+        em.getTransaction().commit();
+        em.close();
+    }
+
+    @AfterClass
+    public static void afterClass() {
+        emf.close();
+    }
+
+}