HibernateUtils整合工具类

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;

public class HibernateUtils {

// 1.创建工厂对象;
private static SessionFactory sessionFactory;

// 2.初始化工厂对象;
static {
sessionFactory = new Configuration().configure().buildSessionFactory();
}

// 3.获得Session;
public static Session getSession() {

return sessionFactory.openSession();

}

}

 

 

以上代码获得会话工厂类,但是会话开始之前要有一个开启事务,所以两者不能在一起使用,只能获取Session之后再开启事务;

For Example;

public class Demo1 {

@Test
public void demo1() {
//	// 5.开启事务;

Session openSession = null;
Transaction beginTransaction = null;
try {
openSession = HibernateUtils.getSession();
beginTransaction = openSession.beginTransaction();
// 6.操作数据库;
Query createQuery = openSession.createQuery("from Admin");
System.out.println(createQuery.list());
} catch (HibernateException e) {
// TODO Auto-generated catch block
e.printStackTrace();
// 7. 提交事务;
beginTransaction.commit();
// 8 关闭资源;
openSession.close();
}

}

}

　　

 源代码;

import org.hibernate.Query;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.classic.Session;
import org.junit.Test;

public class Demo1 {
    
    
    @Test
    public void demo1() {
        
        // 1.获取加载配置资源的对象;
        Configuration configuration = new Configuration();
        // 2.加载资源配置;
        // 当不写路径的时候,默认资源文件在src目录下;
        configuration.configure();
        
        // 3.创建Session会话对象;
        SessionFactory sessionFactory = configuration.buildSessionFactory();
        // 4.开启会话;
        Session openSession = sessionFactory.openSession();
        // 5.开启事务;
        Transaction beginTransaction = openSession.beginTransaction();
        // 6.操作数据库;
        Query createQuery = openSession.createQuery("from Admin");
        
        System.out.println(createQuery.list().size());
        // 7. 提交事务;
        beginTransaction.commit();
        // 8 关闭资源;
        openSession.close();
        sessionFactory.close();
        
    }
    
}