change to lazy fetching in *toOne relationships and modified repository queries accordingy with join fetch to avoid n+1 queries

chatto/src/main/java/org/ros/chatto/model/ChatMessage.java

@@ -4,6 +4,7 @@ import java.util.Date;
 
 import javax.persistence.Column;
 import javax.persistence.Entity;
+import javax.persistence.FetchType;
 import javax.persistence.GeneratedValue;
 import javax.persistence.GenerationType;
 import javax.persistence.Id;
@@ -23,13 +24,13 @@ public class ChatMessage {
 	@GeneratedValue(strategy = GenerationType.IDENTITY)
 	@Column(name = "m_id")
 	private Long messageID;
-	@OneToOne
+	@OneToOne(fetch = FetchType.LAZY)
 	@JoinColumn(name = "from_user")
 	private ChatUser fromUser;
-	@OneToOne
+	@OneToOne(fetch = FetchType.LAZY)
 	@JoinColumn(name = "to_user")
 	private ChatUser toUser;
-	@OneToOne
+	@OneToOne(fetch = FetchType.LAZY)
 	@JoinColumn(name = "message")
 	private MessageCipher messageCipher;
 	@Temporal(TemporalType.TIMESTAMP)

chatto/src/main/java/org/ros/chatto/model/UserRole.java

@@ -1,6 +1,7 @@
 package org.ros.chatto.model;
 
 import javax.persistence.Entity;
+import javax.persistence.FetchType;
 import javax.persistence.Id;
 import javax.persistence.JoinColumn;
 import javax.persistence.ManyToOne;
@@ -14,12 +15,12 @@ public class UserRole {
 	@Id
 	private int id;
 	
-	@ManyToOne
+	@ManyToOne(fetch = FetchType.LAZY)
     @JoinColumn(name = "user_id")
 	@JsonManagedReference
     private ChatUser user;
 	
-	@ManyToOne
+	@ManyToOne(fetch = FetchType.LAZY)
 	@JoinColumn(name = "role_id")
 	@JsonManagedReference
 	private Role role;

chatto/src/main/java/org/ros/chatto/repository/ChatMessageRepository.java

@@ -1,6 +1,5 @@
 package org.ros.chatto.repository;
 
-import java.awt.print.Pageable;
 import java.util.Date;
 import java.util.List;
 
@@ -16,16 +15,16 @@ public interface ChatMessageRepository extends JpaRepository<ChatMessage, Long>
 //	@Query("select ur from UserRole ur where ur.user.userID = ?1")
 //	@Query("select m from ChatMessage  m where m.toUser.userID = ?1 or m.toUser.userID = ?2 and "
 //			+ "m.fromUser.userID = ?1 or m.fromUser.userID = ?2 order by m.messageTime asc")
-	@Query("select m from ChatMessage  m where (m.toUser.userName = ?1 or m.toUser.userName = ?2) and "
+	@Query("select m from ChatMessage  m join fetch m.messageCipher where (m.toUser.userName = ?1 or m.toUser.userName = ?2) and "
 			+ "(m.fromUser.userName = ?1 or m.fromUser.userName = ?2) order by m.messageTime asc")
 	public List<ChatMessage> getAllMessages(String fromUser, String toUser);
 	
-	@Query("select m from ChatMessage  m where (m.toUser.userName = ?1 or m.toUser.userName = ?2) and "
+	@Query("select m from ChatMessage  m join fetch m.messageCipher where (m.toUser.userName = ?1 or m.toUser.userName = ?2) and "
 			+ "(m.fromUser.userName = ?1 or m.fromUser.userName = ?2)  and"
 			+ "(m.messageTime > ?3) order by m.messageTime asc")
 	public List<ChatMessage> getNewMessages(String fromUser, String toUser, Date lastMessageTime);
 	
-	@Query("select m from ChatMessage  m where (m.toUser.userName = ?1 or m.toUser.userName = ?2) and "
+	@Query("select m from ChatMessage  m join fetch m.messageCipher where (m.toUser.userName = ?1 or m.toUser.userName = ?2) and "
 			+ "(m.fromUser.userName = ?1 or m.fromUser.userName = ?2) order by m.messageTime asc")
 	public List<ChatMessage> getAllMessages(String fromUser, String toUser, PageRequest pageRequest);
 	

chatto/src/main/java/org/ros/chatto/repository/UserRoleRepository.java

@@ -9,12 +9,12 @@ import org.springframework.stereotype.Repository;
 
 @Repository
 public interface UserRoleRepository extends JpaRepository<UserRole, Long> {
-	@Query("select ur from UserRole ur where ur.user.userID = ?1")
+	@Query("select ur from UserRole ur join fetch  ur.user join fetch ur.role where ur.user.userID = ?1")
 	public List<UserRole> findByUser(int userID);
 
-	@Query("select ur from UserRole ur where ur.user.userName = ?1")
+	@Query("select ur from UserRole ur join fetch ur.user join fetch ur.role where ur.user.userName = ?1")
 	public List<UserRole> findByUser(String username);
 
-	@Query("select ur.user.userName from UserRole ur where ur.role.roleID = 2")
+	@Query("select ur.user.userName from UserRole ur join ur.role where ur.role.roleID = 2")
 	public List<String> getAllRegularUser();
 }

chatto/src/main/java/org/ros/chatto/repository/UserSessionRepository.java

@@ -7,6 +7,6 @@ import org.springframework.stereotype.Repository;
 
 @Repository
 public interface UserSessionRepository extends JpaRepository<UserSession, Long> {
-	@Query("select us from UserSession us where us.user.userName = ?1 ")
+	@Query("select us from UserSession us join fetch us.user where us.user.userName = ?1 ")
 	public UserSession findByUserName(String userName);
 }

chatto/src/main/resources/application.properties

@@ -13,6 +13,8 @@ spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.MySQL5InnoDBDial
 # Hibernate ddl auto (create, create-drop, validate, update)
 spring.jpa.hibernate.ddl-auto = none
 
+spring.jpa.properties.hibernate.generate_statistics=true
+logging.level.org.hibernate.stat=debug
 logging.level.org.springframework.web=DEBUG
 logging.level.web=DEBUG
 logging.level.org.hibernate.SQL=DEBUG

chatto/src/test/java/org/ros/chatto/ChattoApplicationTests.java

@@ -2,19 +2,14 @@ package org.ros.chatto;
 
 import org.junit.Test;
 import org.junit.runner.RunWith;
-import org.mockito.Mock;
+import org.ros.chatto.repository.UserRoleRepository;
-import org.mockito.Mockito;
+import org.slf4j.Logger;
-import org.ros.chatto.model.ChatMessage;
+import org.slf4j.LoggerFactory;
-import org.ros.chatto.model.ChatUser;
-import org.ros.chatto.repository.ChatMessageRepository;
-import org.ros.chatto.repository.UserRepository;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.test.context.junit4.SpringRunner;
-import static org.mockito.ArgumentMatchers.any;
+
-import static org.mockito.Mockito.times;
+import java.util.List;
-import static org.mockito.Mockito.verify;
-import static org.mockito.Mockito.when;
 
 @RunWith(SpringRunner.class)
 @SpringBootTest
@@ -28,6 +23,11 @@ public class ChattoApplicationTests {
 //	
 //	@Autowired
 //	UserRepository userRepository;
+	
+	@Autowired
+	UserRoleRepository userRoleRepository;
+	
+	private final Logger logger = LoggerFactory.getLogger(ChattoApplicationTests.class);
 //
 	@Test
 	public void contextLoads() {
@@ -38,6 +38,12 @@ public class ChattoApplicationTests {
 //		chatMessageRepository.findAll().toString();
 //	}
 	
+	@Test 
+	public void testRepo() {
+		List<String> list = userRoleRepository.getAllRegularUser();
+		logger.info("List = {} ", list);
+	}
+	
 //	@Test
 //	public void testSave() {
 //		ChatUser fromUser = new ChatUser();