mysql事务隔离级别——读已提交

 设置事务隔离为读已提交

	@Test
	  void test() throws InterruptedException {
	    try (SqlSession session = sqlSessionFactory.openSession(TransactionIsolationLevel.READ_COMMITTED)) {
	//    try (SqlSession session = sqlSessionFactory.openSession(TransactionIsolationLevel.READ_UNCOMMITTED)) {
	      // 开启事务
	      List<User> list = session.selectList("getAllUsers");
	      assertEquals(5, list.size());
	
	      // 开启子线程就相当于开启了一个事务
	      Thread thread1 = startThread();
	
	      // 等待子线程修改数据，但是并没有提交
	      Thread.sleep(1000);
	
	      // 看本次是否读到脏数据
	      List<User> list2 = session.selectList("getAllUsers");
	      assertEquals(5, list2.size());
	
	      // 等待子线程执行结束
	      thread1.join();
	
	      // 暴露了不能重复读取问题
	      List<User> list3 = session.selectList("getAllUsers");
	      assertEquals(6, list3.size());
	    }
	
	  }