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  • Hibernate之openSession与getCurrentSession的区别

    openSession 与 getCurrentSession的区别
    (1)openSession 每一次获得的是一个全新的session对象,而getCurrentSession获得的是与当前线程绑定的session对象;
    (2)openSession不需要配置,而getCurrentSession需要配置

    <property name="current_session_context_class">thread</property> 

    (3)openSession需要手动关闭,而getCurrentSession系统自动关闭

    openSession出来的session要通过:session.close(),
    
    而getSessionCurrent出来的session系统自动关闭,如果自己关闭会报错

    (4)Session是线程不同步的,要保证线程安全就要使用getCurrentSession

    下面这段代码运行后可比较它们的(1)

    package cn.blog.test;
    
    import org.hibernate.Session;
    import org.hibernate.SessionFactory;
    import org.hibernate.cfg.Configuration;
    
    public class Test {
    
        
    //openSession与getCurrentSession对比
    
             public static void main(String[] args) {  
                  
                    Configuration configuration = new Configuration().configure();  
                    SessionFactory sf = configuration.buildSessionFactory();  
                      
                    Session sessionOpen1 = sf.openSession();  
                    Session sessionOpen2 = sf.openSession();  
                      
                    Session sessionThread1 = sf.getCurrentSession();  
                    Session sessionThread2 = sf.getCurrentSession();  
                      
                    System.out.println(sessionOpen1.hashCode() + "<-------->" + sessionOpen2.hashCode());  //每次创建都是新的session对象
                    System.out.println(sessionThread1.hashCode() + "<-------->" + sessionThread2.hashCode());  //每次获得的是当前session
        
    }
             
    }
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  • 原文地址:https://www.cnblogs.com/youcong/p/9832352.html
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