我只是在尝试乐观锁定.
我有以下课程：
@Entity
public class Student {
private Integer id;
private String firstName;
private String lastName;
private Integer version;
@Version
public Integer getVersion() {
return version;
}
//all other getters ommited.
}
现在我正在抓住其中一个学生并尝试同时更新其属性.
Thread t1 = new Thread(new MyRunnable(id));
Thread t2 = new Thread(new MyRunnable(id));
t1.start();
t2.start();
和MyRunnable内部：
public class MyRunnable implements Runnable {
private Integer id;
@Override
public void run() {
Session session = HibernateUtil.getSessionFactory().openSession();
session.beginTransaction();
Student student = (Student) session.load(Student.class,id);
student.setFirstName("xxxx");
session.save(student);
session.getTransaction().commit();
System.out.println("Done");
}
public MyRunnable(Integer id){
this.id = id;
}
}
第一个事务成功更新对象和第二个事务抛出的情况：
org.hibernate.StaleObjectStateException: Row was updated or deleted by another transaction (or unsaved-value mapping was incorrect): [com.vanilla.entity.Student#1]
还行吧.
我的问题是：@H_301_21@1)如果我希望第二个事务什么也不做,并且不抛出任何异常,我该怎么办？
2)如果我希望第二个事务覆盖第一个事务更新的数据,我该怎么办？
谢谢.
