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项目结构

--src/main/java----com.easy.c_hql------HibernateUtils.java------TestApp.java------User.java------hibernate.cfg.xml------User.hbm.xml

User.java

public class User {	private Integer id;	private String username;	private Integer age;

User.hbm.xml

hibernate.cfg.xml

    	
     		
      
       com.mysql.jdbc.Driver
      		
      
       jdbc:mysql://localhost:3306/test
      		
      
       root
      		
      
       123456
      				
      
       true
      		
      
       true
      				
      
       update
      		
      	
     
    

HibernateUtils.java

public class HibernateUtils {	private static SessionFactory sessionFactory;	static{		URL url=HibernateUtils.class.getClass().getResource("/com/easy/c_hql/hibernate.cfg.xml");		Configuration conf=new Configuration().configure(url);				sessionFactory =conf.buildSessionFactory();				Runtime.getRuntime().addShutdownHook(new Thread(				new Runnable() {					@Override					public void run() {						System.out.println("虚拟机关闭，释放资源");						sessionFactory.close();					}				}));	}		public static Session openSession(){		return sessionFactory.openSession();	}		public static Session getCurrentSession(){		return sessionFactory.getCurrentSession();	}}

UT

查询多行数据

public void test_query_multi_rows(){                              	Session session = HibernateUtils.openSession();               	                                                              	Query query = session.createQuery("from com.easy.c_hql.User");	List
    
     list=query.list();                                  	System.out.println(list);                                     	                                                              	session.close();                                              }
    

查询单行数据

public void test_query_single_row(){                                              	Session session = HibernateUtils.openSession();                               	                                                                              	Query query = session.createQuery("from com.easy.c_hql.User u where u.id=1"); 	User user =(User)query.uniqueResult();                                        	System.out.println(user);                                                     	                                                                              	session.close();                                                              }