java 42 lines · 5 steps

Auditing timestamps with a JPA MappedSuperclass in Spring

A reusable base class stamps created_at and updated_at automatically using JPA lifecycle callbacks.

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Spring Intermediate jpa auditing lifecycle-callbacks inheritance entity-listeners
1package com.acme.catalog.persistence;
2 
3import jakarta.persistence.Column;
4import jakarta.persistence.EntityListeners;
5import jakarta.persistence.MappedSuperclass;
6import jakarta.persistence.PrePersist;
7import jakarta.persistence.PreUpdate;
8import java.time.Instant;
9 
10@MappedSuperclass
11@EntityListeners(Auditable.AuditListener.class)
12public abstract class Auditable {
13 
14 @Column(name = "created_at", nullable = false, updatable = false)
15 private Instant createdAt;
16 
17 @Column(name = "updated_at", nullable = false)
18 private Instant updatedAt;
19 
20 public Instant getCreatedAt() {
21 return createdAt;
22 }
23 
24 public Instant getUpdatedAt() {
25 return updatedAt;
26 }
27 
28 static class AuditListener {
29 
30 @PrePersist
31 void onCreate(Auditable entity) {
32 Instant now = Instant.now();
33 entity.createdAt = now;
34 entity.updatedAt = now;
35 }
36 
37 @PreUpdate
38 void onUpdate(Auditable entity) {
39 entity.updatedAt = Instant.now();
40 }
41 }
42}
01 / 01
STEP 01

Walkthrough

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Three takeaways
  1. 1A @MappedSuperclass shares columns and behavior with entities without being an entity itself.
  2. 2JPA lifecycle callbacks let you populate fields at persist and update time with no service code.
  3. 3Making created_at non-updatable protects the original creation moment from later writes.

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