java 用于日历的休眠 @CreationTimestamp @UpdateTimestamp
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Hibernate @CreationTimestamp @UpdateTimestamp for Calendar
提问by Sergii
In my entity I have fields:
在我的实体中，我有字段：
@UpdateTimestamp
@Column
private java.util.Calendar modifiedDate;
@CreationTimestamp
@Column
private java.util.Calendar createdDate;
These fields are changed by hibernate. I see result saved to DB. In DB saved data without time, how I could explain to hibernate that calendar should be saved with current dateTime?
这些字段由休眠更改。我看到结果保存到数据库。在没有时间的 DB 保存数据中，我如何解释休眠日历应该与当前日期时间一起保存？
P.S.
I saw workarounds like method annotations @PreUpdate@PrePersisti do not think i need ones.
PS我看到了像方法注释@PreUpdate@PrePersist这样的解决方法，我认为我不需要。
回答by Maciej Kowalski
According to the JPA spec regarding the Calendar data type:
根据有关日历数据类型的 JPA 规范：
@Temporal- This annotation must be specified for persistent fields or properties of type java.util.Date and java.util.Calendar.
@Temporal- 必须为 java.util.Date 和 java.util.Calendar 类型的持久字段或属性指定此注释。
In your case you should use:
在您的情况下，您应该使用：
@Temporal(TemporalType.TIMESTAMP)
for both of the fields.
对于这两个领域。
Another solution would be to simply change from java.util.Calendar to java.sql.Timestamp:
另一种解决方案是简单地从 java.util.Calendar 更改为 java.sql.Timestamp：
@UpdateTimestamp
@Column
private java.sql.Timestamp modifiedDate;
@CreationTimestamp
@Column
private java.sql.Timestamp createdDate;
回答by Fabien Leborgne
I think you can use @CreationTimestampand @UpdateTimestampannotations but you have to specify the TemporalType as a Timestamp.
我认为您可以使用@CreationTimestamp和@UpdateTimestamp注释，但您必须将 TemporalType 指定为时间戳。
@CreationTimestamp
@Temporal(TemporalType.TIMESTAMP)
@Column(name = "createdDate")
private java.util.Calendar createdDate;
@UpdateTimestamp
@Temporal(TemporalType.TIMESTAMP)
@Column(name = "modifiedDate")
private java.util.Calendar modifiedDate;
Otherwise, as you said you can use @PrePersistand @PreUpdateas follow:
否则，正如您所说，您可以使用@PrePersist和@PreUpdate如下：
@PrePersist
protected void onCreate() {
created = Calendar.getInstance();
}
@PreUpdate
protected void onUpdate() {
updated = Calendar.getInstance();
}
回答by Sergii
I have considered alternative solution way via spring, it works fine, and easy to shift data in tests. Original description.
我已经考虑过通过 spring 的替代解决方案，它工作正常，并且易于在测试中移动数据。原始描述。
