package cn.itcast.test;java
import java.util.Set;session
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.junit.Test;dom
import cn.itcast.domain.Customer;
import cn.itcast.domain.LinkMan;
import cn.itcast.domain.SysRole;
import cn.itcast.domain.SysUser;
import cn.itcast.utils.HibernateUtils;.net
public class TestManyToMany {hibernate
/**
* 多對多保存
* 結果報錯,由於用戶和角色都具有外鍵維護的權利
* 怎麼解決:讓其中一方放棄外鍵維護權,讓角色放棄外鍵維護權
*/
@Test
public void test1(){
SysUser user1 = new SysUser();
user1.setUserName("用戶1");
SysUser user2 = new SysUser();
user2.setUserName("用戶2");
SysRole role1 = new SysRole();
role1.setRoleName("角色1");
SysRole role2 = new SysRole();
role2.setRoleName("角色2");
SysRole role3 = new SysRole();
role3.setRoleName("角色3");
//創建關係
user1.getRoles().add(role1);
user1.getRoles().add(role2);
user2.getRoles().add(role2);
user2.getRoles().add(role3);
role1.getUsers().add(user1);
role2.getUsers().add(user1);
role2.getUsers().add(user2);
role3.getUsers().add(user2);
Session session = HibernateUtils.getCurrentSession();
Transaction tx = session.beginTransaction();
//保存
session.save(user1);
session.save(user2);
session.save(role1);
session.save(role2);
session.save(role3);
tx.commit();
}
/**
* 多對多級聯保存:保存用戶級聯保存角色
*/
@Test
public void test2(){
SysUser user1 = new SysUser();
user1.setUserName("用戶1");
SysUser user2 = new SysUser();
user2.setUserName("用戶2");
SysRole role1 = new SysRole();
role1.setRoleName("角色1");
SysRole role2 = new SysRole();
role2.setRoleName("角色2");
SysRole role3 = new SysRole();
role3.setRoleName("角色3");
//創建關係
user1.getRoles().add(role1);
user1.getRoles().add(role2);
user2.getRoles().add(role2);
user2.getRoles().add(role3);
role1.getUsers().add(user1);
role2.getUsers().add(user1);
role2.getUsers().add(user2);
role3.getUsers().add(user2);
Session session = HibernateUtils.getCurrentSession();
Transaction tx = session.beginTransaction();
//保存用戶,級聯保存角色
session.save(user1);
session.save(user2);
tx.commit();
}
/**
* 多對多刪除:刪除用戶
*/
@Test
public void test3(){
Session session = HibernateUtils.getCurrentSession();
Transaction tx = session.beginTransaction();
SysUser sysUser = session.get(SysUser.class, 1L);
session.delete(sysUser);
tx.commit();
}
/**
* 多對多刪除:刪除角色
* 結果失敗,由於角色已經放棄外鍵維護權,不會管中間的數據,直接刪除角色數據,可是中間表有數據關聯角色
*/
@Test
public void test4(){
Session session = HibernateUtils.getCurrentSession();
Transaction tx = session.beginTransaction();
SysRole sysRole = session.get(SysRole.class,1L);
//獲取該角色下的用戶
Set<SysUser> users = sysRole.getUsers();
for (SysUser sysUser : users) {
//獲取用戶全部的角色,刪除該角色
sysUser.getRoles().remove(sysRole);
}
session.delete(sysRole);
tx.commit();
}
/**
* 多對多更新:一號用戶把角色1換成角色3
*/
@Test
public void test5(){
Session session = HibernateUtils.getCurrentSession();
Transaction tx = session.beginTransaction();
SysUser sysUser = session.get(SysUser.class, 1L);
SysRole sysRole1 = session.get(SysRole.class,1L);
SysRole sysRole3 = session.get(SysRole.class,3L);
//創建關係
sysUser.getRoles().add(sysRole3);
// sysRole3.getUsers().add(sysUser);
sysUser.getRoles().remove(sysRole1);
tx.commit();
}
rem
/**
* 多對多級聯刪除:刪除用戶級聯刪除角色
* 刪除失敗:由於刪除用戶級聯刪除角色,角色放棄外鍵維護權了,角色刪除不了,整個操做失敗
* 解決方案:在兩邊都加級聯。
* 注意:在多對多中不須要配置級聯刪除
*/
@Test
public void test6(){
Session session = HibernateUtils.getCurrentSession();
Transaction tx = session.beginTransaction();
SysUser sysUser = session.get(SysUser.class,1L);
session.delete(sysUser);
tx.commit();
}
}
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