首页 > 移动平台 > 详细

@MappedSuperclass的用法

时间:2017-04-04 20:38:36      阅读:230      评论:0      收藏:0      [点我收藏+]

实体类baseEntity.java

package com.rock.cft.hibernate;
import java.util.Date;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.MappedSuperclass;
//@MappedSuperclass 用在父类上面。当这个类肯定是父类时,加此标注。如果改成@Entity,则继承后,多个类继承,只会生成一个表,而不是多个继承,生成多个表
@MappedSuperclass
public abstract class BaseEntity {
  private Integer id;// 数据库主键
 private Date creationTime;//创建时间
 private Date modificationTime;//修改时间
 
 @Id
 @GeneratedValue(strategy = GenerationType.AUTO)
 public Integer getId() {
  return id;
 }
 public void setId(Integer id) {
  this.id = id;
 }
 public Date getCreationTime() {
  return creationTime;
 }
 public void setCreationTime(Date creationTime) {
  this.creationTime = creationTime;
 }
 public Date getModificationTime() {
  return modificationTime;
 }
 public void setModificationTime(Date modificationTime) {
  this.modificationTime = modificationTime;
 }
 
}
实体类Test_No1.java
package com.rock.cft.test.model;
import java.io.Serializable;
import java.util.Date;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Table;
import com.rock.cft.hibernate.BaseEntity;
@Entity
@Table(name="test_no2")
public class Test_No1 extends BaseEntity implements Serializable {
 

 private String name;
 private int age;
 
 public String getName() {
  return name;
 }
 public void setName(String name) {
  this.name = name;
 }
 public int getAge() {
  return age;
 }
 public void setAge(int age) {
  this.age = age;
 }
  
}
实体类Test_NO2.java
package com.rock.cft.test.model;
import java.io.Serializable;
import java.util.Date;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Table;
import com.rock.cft.hibernate.BaseEntity;
@Entity
@Table(name="test_no2")
public class Test_NO2 extends BaseEntity implements Serializable {
 
 
 private Date testBri;
 
 private String testAdr;
 
 public Date getTestBri() {
  return testBri;
 }
 public void setTestBri(Date testBri) {
  this.testBri = testBri;
 }
 public String getTestAdr() {
  return testAdr;
 }
 public void setTestAdr(String testAdr) {
  this.testAdr = testAdr;
 }
 
 


 
 
} 
这样在生成表的时候只生成了:test_no1、test_no2两张表,而且两张表中都含有id、creationTime、modificationTime三个属性
但是如果把@MappedSuperclass换成@Entity那么就会另外在生成一张baseEntity的表

@MappedSuperclass的用法

原文:http://www.cnblogs.com/zhaoyan001/p/6665993.html

(0)
(0)
   
举报
评论 一句话评论(0
关于我们 - 联系我们 - 留言反馈 - 联系我们:wmxa8@hotmail.com
© 2014 bubuko.com 版权所有
打开技术之扣,分享程序人生!