JPA Criteria test

spring-jpa/pom.xml

@@ -46,6 +46,13 @@
 			<version>${mysql-connector-java.version}</version>
 			<scope>runtime</scope>
 		</dependency>
+		<dependency>
+			<groupId>org.springframework.data</groupId>
+			<artifactId>spring-data-jpa</artifactId>
+			<version>1.6.0.RELEASE</version>
+    		<scope>compile</scope>
+		</dependency>
+
 
 		<!-- validation -->
 

spring-jpa/src/main/java/org/baeldung/persistence/dao/IUserDAO.java

@@ -0,0 +1,11 @@
+package org.baeldung.persistence.dao;
+
+import java.util.List;
+
+import org.baeldung.persistence.model.User;
+
+public interface IUserDAO {
+    List<User> searchUser(String first, String last, int minAge);
+
+    void save(User entity);
+}

spring-jpa/src/main/java/org/baeldung/persistence/dao/UserDAO.java

@@ -0,0 +1,43 @@
+package org.baeldung.persistence.dao;
+
+import java.util.List;
+
+import javax.persistence.EntityManager;
+import javax.persistence.PersistenceContext;
+import javax.persistence.criteria.CriteriaBuilder;
+import javax.persistence.criteria.CriteriaQuery;
+import javax.persistence.criteria.Predicate;
+import javax.persistence.criteria.Root;
+
+import org.baeldung.persistence.model.User;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public class UserDAO implements IUserDAO {
+
+    @PersistenceContext
+    private EntityManager entityManager;
+
+    @Override
+    public List<User> searchUser(final String first, final String last, final int minAge) {
+        final CriteriaBuilder builder = entityManager.getCriteriaBuilder();
+        final CriteriaQuery<User> query = builder.createQuery(User.class);
+        final Root r = query.from(User.class);
+
+        Predicate predicate = builder.conjunction();
+        predicate = builder.and(predicate, builder.like(r.get("firstName"), "%" + first + "%"));
+        predicate = builder.and(predicate, builder.like(r.get("lastName"), "%" + last + "%"));
+        predicate = builder.and(predicate, builder.greaterThanOrEqualTo(r.get("age"), minAge));
+
+        query.where(predicate);
+
+        final List<User> result = entityManager.createQuery(query).getResultList();
+        return result;
+    }
+
+    @Override
+    public void save(final User entity) {
+        entityManager.persist(entity);
+    }
+
+}

spring-jpa/src/main/java/org/baeldung/persistence/model/User.java

@@ -0,0 +1,96 @@
+package org.baeldung.persistence.model;
+
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+
+@Entity
+public class User {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.AUTO)
+    private Long id;
+
+    private String firstName;
+
+    private String lastName;
+
+    private String email;
+
+    private int age;
+
+    public User() {
+        super();
+    }
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(final Long id) {
+        this.id = id;
+    }
+
+    public String getFirstName() {
+        return firstName;
+    }
+
+    public void setFirstName(final String firstName) {
+        this.firstName = firstName;
+    }
+
+    public String getLastName() {
+        return lastName;
+    }
+
+    public void setLastName(final String lastName) {
+        this.lastName = lastName;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    public void setEmail(final String username) {
+        email = username;
+    }
+
+    public int getAge() {
+        return age;
+    }
+
+    public void setAge(final int age) {
+        this.age = age;
+    }
+
+    @Override
+    public int hashCode() {
+        final int prime = 31;
+        int result = 1;
+        result = prime * result + ((email == null) ? 0 : email.hashCode());
+        return result;
+    }
+
+    @Override
+    public boolean equals(final Object obj) {
+        if (this == obj)
+            return true;
+        if (obj == null)
+            return false;
+        if (getClass() != obj.getClass())
+            return false;
+        final User user = (User) obj;
+        if (!email.equals(user.email))
+            return false;
+        return true;
+    }
+
+    @Override
+    public String toString() {
+        final StringBuilder builder = new StringBuilder();
+        builder.append("User [firstName=").append(firstName).append("]").append("[lastName=").append(lastName).append("]").append("[username").append(email).append("]");
+        return builder.toString();
+    }
+
+}

spring-jpa/src/main/java/org/baeldung/persistence/service/UserService.java

@@ -0,0 +1,28 @@
+package org.baeldung.persistence.service;
+
+import java.util.List;
+
+import org.baeldung.persistence.dao.IUserDAO;
+import org.baeldung.persistence.model.User;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+@Service
+@Transactional
+public class UserService {
+    @Autowired
+    private IUserDAO dao;
+
+    public UserService() {
+        super();
+    }
+
+    public void saveUser(final User user) {
+        dao.save(user);
+    }
+
+    public List<User> searchUser(final String first, final String last, final int minAge) {
+        return dao.searchUser(first, last, minAge);
+    }
+}

spring-jpa/src/test/java/org/baeldung/persistence/query/JPACriteriaQueryTest.java

@@ -0,0 +1,85 @@
+package org.baeldung.persistence.query;
+
+import static org.junit.Assert.assertEquals;
+
+import java.util.List;
+
+import org.baeldung.config.PersistenceJPAConfig;
+import org.baeldung.persistence.model.User;
+import org.baeldung.persistence.service.UserService;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.test.context.support.AnnotationConfigContextLoader;
+import org.springframework.test.context.transaction.TransactionConfiguration;
+import org.springframework.transaction.annotation.Transactional;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration(classes = { PersistenceJPAConfig.class }, loader = AnnotationConfigContextLoader.class)
+@Transactional
+@TransactionConfiguration
+public class JPACriteriaQueryTest {
+
+    @Autowired
+    private UserService userService;
+
+    private User user_john;
+
+    private User user_tom;
+
+    @Before
+    public void init() {
+        user_john = new User();
+        user_john.setFirstName("John");
+        user_john.setLastName("Doe");
+        user_john.setEmail("[email protected]");
+        user_john.setAge(22);
+        userService.saveUser(user_john);
+
+        user_tom = new User();
+        user_tom.setFirstName("Tom");
+        user_tom.setLastName("Doe");
+        user_tom.setEmail("[email protected]");
+        user_tom.setAge(26);
+        userService.saveUser(user_tom);
+    }
+
+    @Test
+    public void givenFirstAndLastName_whenGettingListOfUsers_thenCorrect() {
+        final List<User> result = userService.searchUser("John", "Doe", 0);
+
+        assertEquals(1, result.size());
+        assertEquals(user_john.getEmail(), result.get(0).getEmail());
+    }
+
+    @Test
+    public void givenLast_whenGettingListOfUsers_thenCorrect() {
+        final List<User> result = userService.searchUser("", "doe", 0);
+        assertEquals(2, result.size());
+    }
+
+    @Test
+    public void givenLastAndAge_whenGettingListOfUsers_thenCorrect() {
+        final List<User> result = userService.searchUser("", "doe", 25);
+
+        assertEquals(1, result.size());
+        assertEquals(user_tom.getEmail(), result.get(0).getEmail());
+    }
+
+    @Test
+    public void givenWrongFirstAndLast_whenGettingListOfUsers_thenCorrect() {
+        final List<User> result = userService.searchUser("Adam", "Fox", 0);
+        assertEquals(0, result.size());
+    }
+
+    @Test
+    public void givenPartialFirstAndLast_whenGettingListOfUsers_thenCorrect() {
+        final List<User> result = userService.searchUser("jo", "", 0);
+
+        assertEquals(1, result.size());
+        assertEquals(user_john.getEmail(), result.get(0).getEmail());
+    }
+}