BAEL-3770 JPA Entity Lifecycle Events (#8590)

persistence-modules/spring-data-jpa-4/src/main/java/com/baeldung/lifecycleevents/SpringBootLifecycleEventApplication.java

@@ -0,0 +1,11 @@
+package com.baeldung.lifecycleevents;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class SpringBootLifecycleEventApplication {
+    public static void main(String[] args) {
+        SpringApplication.run(SpringBootLifecycleEventApplication.class, args);
+    }
+}

persistence-modules/spring-data-jpa-4/src/main/java/com/baeldung/lifecycleevents/model/AuditTrailListener.java

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+package com.baeldung.lifecycleevents.model;
+
+import javax.persistence.PostLoad;
+import javax.persistence.PostPersist;
+import javax.persistence.PostRemove;
+import javax.persistence.PostUpdate;
+import javax.persistence.PrePersist;
+import javax.persistence.PreRemove;
+import javax.persistence.PreUpdate;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
+public class AuditTrailListener {
+    private static Log log = LogFactory.getLog(AuditTrailListener.class);
+    
+    @PrePersist
+    @PreUpdate
+    @PreRemove
+    private void beforeAnyUpdate(User user) {
+        if (user.getId() == 0) {
+            log.info("[USER AUDIT] About to add a user");
+        } else {
+            log.info("[USER AUDIT] About to update/delete user: " + user.getId());
+        }
+    }
+    
+    @PostPersist
+    @PostUpdate
+    @PostRemove
+    private void afterAnyUpdate(User user) {
+        log.info("[USER AUDIT] add/update/delete complete for user: " + user.getId());
+    }
+    
+    @PostLoad
+    private void afterLoad(User user) {
+        log.info("[USER AUDIT] user loaded from database: " + user.getId());
+    }
+}

persistence-modules/spring-data-jpa-4/src/main/java/com/baeldung/lifecycleevents/model/User.java

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+package com.baeldung.lifecycleevents.model;
+
+import javax.persistence.Entity;
+import javax.persistence.EntityListeners;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import javax.persistence.PostLoad;
+import javax.persistence.PostPersist;
+import javax.persistence.PostRemove;
+import javax.persistence.PostUpdate;
+import javax.persistence.PrePersist;
+import javax.persistence.PreRemove;
+import javax.persistence.PreUpdate;
+import javax.persistence.Transient;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
+@Entity
+@EntityListeners(AuditTrailListener.class)
+public class User {
+    private static Log log = LogFactory.getLog(User.class);
+
+    @Id
+    @GeneratedValue
+    private int id;
+    
+    private String userName;
+    private String firstName;
+    private String lastName;
+    @Transient
+    private String fullName;
+    
+    public int getId() {
+        return id;
+    }
+    
+    public void setId(int id) {
+        this.id = id;
+    }
+    
+    public String getUserName() {
+        return userName;
+    }
+    
+    public void setUserName(String userName) {
+        this.userName = userName;
+    }
+    
+    public String getFirstName() {
+        return firstName;
+    }
+    
+    public void setFirstName(String firstName) {
+        this.firstName = firstName;
+    }
+    
+    public String getLastName() {
+        return lastName;
+    }
+    
+    public void setLastName(String lastName) {
+        this.lastName = lastName;
+    }
+    
+    public String getFullName() {
+        return fullName;
+    }
+    
+    @PrePersist
+    public void logNewUserAttempt() {
+        log.info("Attempting to add new user with username: " + userName);
+    }
+    
+    @PostPersist
+    public void logNewUserAdded() {
+        log.info("Added user '" + userName + "' with ID: " + id);
+    }
+    
+    @PreRemove
+    public void logUserRemovalAttempt() {
+        log.info("Attempting to delete user: " + userName);
+    }
+    
+    @PostRemove
+    public void logUserRemoval() {
+        log.info("Deleted user: " + userName);
+    }
+    
+    @PreUpdate
+    public void logUserUpdateAttempt() {
+        log.info("Attempting to update user: " + userName);
+    }
+    
+    @PostUpdate
+    public void logUserUpdate() {
+        log.info("Updated user: " + userName);
+    }
+    
+    @PostLoad
+    public void logUserLoad() {
+        fullName = firstName + " " + lastName;
+    }
+}

persistence-modules/spring-data-jpa-4/src/main/java/com/baeldung/lifecycleevents/repository/UserRepository.java

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+package com.baeldung.lifecycleevents.repository;
+
+import org.springframework.data.jpa.repository.JpaRepository;
+
+import com.baeldung.lifecycleevents.model.User;
+
+public interface UserRepository extends JpaRepository<User, Integer> {
+    public User findByUserName(String userName);
+}

persistence-modules/spring-data-jpa-4/src/test/java/lifecycleevents/UserRepositoryIntegrationTest.java

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+package lifecycleevents;
+
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit4.SpringRunner;
+
+import com.baeldung.lifecycleevents.SpringBootLifecycleEventApplication;
+import com.baeldung.lifecycleevents.model.User;
+import com.baeldung.lifecycleevents.repository.UserRepository;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest(classes = SpringBootLifecycleEventApplication.class)
+public class UserRepositoryIntegrationTest {
+
+    @Autowired
+    private UserRepository userRepository;
+    
+    @Before
+    public void setup() {
+        User user = new User();
+        user.setFirstName("Jane");
+        user.setLastName("Smith");
+        user.setUserName("jsmith123");
+        userRepository.save(user);
+    }
+    
+    @After
+    public void cleanup() {
+        userRepository.deleteAll();
+    }
+    
+    @Test
+    public void whenNewUserProvided_userIsAdded() {
+        User user = new User();
+        user.setFirstName("John");
+        user.setLastName("Doe");
+        user.setUserName("jdoe123");
+        user = userRepository.save(user);
+        assertTrue(user.getId() > 0);
+    }
+    
+    @Test
+    public void whenUserNameProvided_userIsLoaded() {
+        User user = userRepository.findByUserName("jsmith123");
+        assertNotNull(user);
+        assertEquals("jsmith123", user.getUserName());
+    }
+    
+    @Test
+    public void whenExistingUserProvided_userIsUpdated() {
+        User user = userRepository.findByUserName("jsmith123");
+        user.setFirstName("Joe");
+        user = userRepository.save(user);
+        assertEquals("Joe", user.getFirstName());
+    }
+    
+    @Test
+    public void whenExistingUserDeleted_userIsDeleted() {
+        User user = userRepository.findByUserName("jsmith123");
+        userRepository.delete(user);
+        user = userRepository.findByUserName("jsmith123");
+        assertNull(user);
+    }
+    
+    @Test
+    public void whenExistingUserLoaded_fullNameIsAvailable() {
+        String expectedFullName = "Jane Smith";
+        User user = userRepository.findByUserName("jsmith123");
+        assertEquals(expectedFullName, user.getFullName());
+    }
+}