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.

Explained by highlit

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

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

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