BAEL-2474 (#5997)

* BAEL-2474

* rename UserRepositoryImpl.java into UserRepositoryCustomImpl.java

persistence-modules/spring-data-jpa/src/main/java/com/baeldung/dao/repositories/user/UserRepository.java

@@ -1,6 +1,7 @@
 package com.baeldung.dao.repositories.user;
 
 import com.baeldung.domain.user.User;
+
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Pageable;
 import org.springframework.data.domain.Sort;
@@ -13,7 +14,7 @@ import java.util.Collection;
 import java.util.List;
 import java.util.stream.Stream;
 
-public interface UserRepository extends JpaRepository<User, Integer> {
+public interface UserRepository extends JpaRepository<User, Integer> , UserRepositoryCustom{
 
     Stream<User> findAllByName(String name);
 

persistence-modules/spring-data-jpa/src/main/java/com/baeldung/dao/repositories/user/UserRepositoryCustom.java

@@ -0,0 +1,10 @@
+package com.baeldung.dao.repositories.user;
+
+import java.util.List;
+import java.util.Set;
+
+import com.baeldung.domain.user.User;
+
+public interface UserRepositoryCustom {
+    List<User> findUserByEmails(Set<String> emails);
+}

persistence-modules/spring-data-jpa/src/main/java/com/baeldung/dao/repositories/user/UserRepositoryCustomImpl.java

@@ -0,0 +1,43 @@
+package com.baeldung.dao.repositories.user;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Set;
+
+import javax.persistence.EntityManager;
+import javax.persistence.PersistenceContext;
+import javax.persistence.criteria.CriteriaBuilder;
+import javax.persistence.criteria.CriteriaQuery;
+import javax.persistence.criteria.Path;
+import javax.persistence.criteria.Predicate;
+import javax.persistence.criteria.Root;
+
+import com.baeldung.domain.user.User;
+
+public class UserRepositoryCustomImpl implements UserRepositoryCustom {
+
+    @PersistenceContext
+    private EntityManager entityManager;
+
+    @Override
+    public List<User> findUserByEmails(Set<String> emails) {
+        CriteriaBuilder cb = entityManager.getCriteriaBuilder();
+        CriteriaQuery<User> query = cb.createQuery(User.class);
+        Root<User> user = query.from(User.class);
+
+        Path<String> emailPath = user.get("email");
+
+        List<Predicate> predicates = new ArrayList<>();
+        for (String email : emails) {
+
+            predicates.add(cb.like(emailPath, email));
+
+        }
+        query.select(user)
+            .where(cb.or(predicates.toArray(new Predicate[predicates.size()])));
+
+        return entityManager.createQuery(query)
+            .getResultList();
+    }
+
+}

persistence-modules/spring-data-jpa/src/test/java/com/baeldung/dao/repositories/UserRepositoryIntegrationTest.java

@@ -18,7 +18,9 @@ import org.springframework.test.context.junit4.SpringRunner;
 import org.springframework.transaction.annotation.Transactional;
 
 import java.util.Collection;
+import java.util.HashSet;
 import java.util.List;
+import java.util.Set;
 import java.util.stream.Stream;
 
 import static org.assertj.core.api.Assertions.assertThat;
@@ -274,9 +276,8 @@ public class UserRepositoryIntegrationTest {
 
         List<User> usersSortByName = userRepository.findAll(new Sort(Sort.Direction.ASC, "name"));
 
-        assertThat(usersSortByName
+        assertThat(usersSortByName.get(0)
-          .get(0)
+            .getName()).isEqualTo(USER_NAME_ADAM);
-          .getName()).isEqualTo(USER_NAME_ADAM);
     }
 
     @Test(expected = PropertyReferenceException.class)
@@ -289,9 +290,8 @@ public class UserRepositoryIntegrationTest {
 
         List<User> usersSortByNameLength = userRepository.findAll(new Sort("LENGTH(name)"));
 
-        assertThat(usersSortByNameLength
+        assertThat(usersSortByNameLength.get(0)
-          .get(0)
+            .getName()).isEqualTo(USER_NAME_ADAM);
-          .getName()).isEqualTo(USER_NAME_ADAM);
     }
 
     @Test
@@ -304,9 +304,8 @@ public class UserRepositoryIntegrationTest {
 
         List<User> usersSortByNameLength = userRepository.findAllUsers(JpaSort.unsafe("LENGTH(name)"));
 
-        assertThat(usersSortByNameLength
+        assertThat(usersSortByNameLength.get(0)
-          .get(0)
+            .getName()).isEqualTo(USER_NAME_ADAM);
-          .getName()).isEqualTo(USER_NAME_ADAM);
     }
 
     @Test
@@ -320,10 +319,9 @@ public class UserRepositoryIntegrationTest {
 
         Page<User> usersPage = userRepository.findAllUsersWithPagination(new PageRequest(1, 3));
 
-        assertThat(usersPage
+        assertThat(usersPage.getContent()
-          .getContent()
+            .get(0)
-          .get(0)
+            .getName()).isEqualTo("SAMPLE1");
-          .getName()).isEqualTo("SAMPLE1");
     }
 
     @Test
@@ -337,10 +335,9 @@ public class UserRepositoryIntegrationTest {
 
         Page<User> usersSortByNameLength = userRepository.findAllUsersWithPaginationNative(new PageRequest(1, 3));
 
-        assertThat(usersSortByNameLength
+        assertThat(usersSortByNameLength.getContent()
-          .getContent()
+            .get(0)
-          .get(0)
+            .getName()).isEqualTo("SAMPLE1");
-          .getName()).isEqualTo("SAMPLE1");
     }
 
     @Test
@@ -370,6 +367,30 @@ public class UserRepositoryIntegrationTest {
         assertThat(updatedUsersSize).isEqualTo(2);
     }
 
+    @Test
+    public void givenUsersInDBWhenFindByEmailsWithDynamicQueryThenReturnCollection() {
+
+        User user1 = new User();
+        user1.setEmail(USER_EMAIL);
+        userRepository.save(user1);
+
+        User user2 = new User();
+        user2.setEmail(USER_EMAIL2);
+        userRepository.save(user2);
+
+        User user3 = new User();
+        user3.setEmail(USER_EMAIL3);
+        userRepository.save(user3);
+
+        Set<String> emails = new HashSet<>();
+        emails.add(USER_EMAIL2);
+        emails.add(USER_EMAIL3);
+
+        Collection<User> usersWithEmails = userRepository.findUserByEmails(emails);
+
+        assertThat(usersWithEmails.size()).isEqualTo(2);
+    }
+
     @After
     public void cleanUp() {
         userRepository.deleteAll();