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();
+    }
+
+}