hibernate_____实现ssh2用的hibernate

1.加hibernate的jar包

2.在模型类中加入注解

代码中的:  @Entity---->import javax.persistence.Entity;
               @Id----->import javax.persistence.Id;
               @GeneratedValue--------->import javax.persistence.GeneratedValue;

是加入的

package cn.com.lrs.model;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;

@Entity
public class User {
	
	private int id;
	private String username;
	private String password;
	
	@Id
	@GeneratedValue
	public int getId() {
		return id;
	}
	public void setId(int id) {
		this.id = id;
	}
	public String getUsername() {
		return username;
	}
	public void setUsername(String username) {
		this.username = username;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
	}
}

 

3.在项目加入SessionFactory工具类

package cn.com.lrs.util;

import org.hibernate.SessionFactory;
import org.hibernate.cfg.AnnotationConfiguration;

public class HibernateUtil {
	
	private static SessionFactory sf;
	
	static {
		sf = new AnnotationConfiguration().configure().buildSessionFactory();
	}
	
	public static SessionFactory getSessionFactory() {
		return sf;
	}
}

 

4.操作---------------------------------------

 

  SessionFactory sf = HibernateUtil.getSessionFactory();
  Session s = sf.getCurrentSession();
  s.beginTransaction();
  
  long count = (Long)s.createQuery("select count(*) from User u where u.username=:username ")
   .setString("username", u.getUsername())//设置数值
   .uniqueResult();//返回结果
  
  s.getTransaction().commit();
  
  if (count > 0) {
   return true;
  }
  return false;

 代替掉以下代码

		Class.forName("com.mysql.jdbc.Driver");
		Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/spring", "root", "ocsoft");
		
		String sqlQuery = "select count(*) from user where username= ?";
		PreparedStatement psQuery = conn.prepareStatement(sqlQuery);
		psQuery.setString(1,u.getUsername());
		ResultSet rs = psQuery.executeQuery();
		rs.next();
		int count = rs.getInt(1);//拿到字段值
		psQuery.close();
		conn.close();
		
		if (count > 0) {
			return true;
		}
		return false;

 

 

你看看hibernate添加信息多么的简单

SessionFactory sf = HibernateUtil.getSessionFactory();
Session s = sf.getCurrentSession();
s.beginTransaction();
s.save(u);
s.getTransaction().commit();

 

 

5.创建Junit测试类(具体看附件)

package cn.com.lrs.service;

import static org.junit.Assert.*;

import org.junit.Test;

public class UserManagerTest {

	@Test
	public void testExists() {
		fail("Not yet implemented");
	}

	@Test
	public void testAdd() {
		fail("Not yet implemented");
	}

}