mybatis入门程序

1、工程结构：

2、核心配置文件：SqlMapConfig.xml

3、sql语句配置文件mapper.xml文件-User.xml：

	
	
	
		select * from user where id = '${value}'
	
	
	
		select * from user where username like '%${value}%'
	

4、数据库表结构：

5、pojo类：User.java

package com.js.mybatis.po;
/**
 * 用户po类
 */
import java.util.Date;

public class User {
	@Override
	public String toString() {
		return "User [id=" + id + ", username=" + username + ", sex=" + sex
				+ ", birthday=" + birthday + ", address=" + address + "]";
	}
	private int id;
	private String username;
	private String sex;
	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 getSex() {
		return sex;
	}
	public void setSex(String sex) {
		this.sex = sex;
	}
	public Date getBirthday() {
		return birthday;
	}
	public void setBirthday(Date birthday) {
		this.birthday = birthday;
	}
	public String getAddress() {
		return address;
	}
	public void setAddress(String address) {
		this.address = address;
	}
	private Date birthday;
	private String address;
}

6、测试类：

package com.js.mybatis.first;

import java.io.IOException;
import java.io.InputStream;
import java.util.Iterator;
import java.util.List;


import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.Before;
import org.junit.Test;
import com.js.mybatis.po.User;

public class MybatisFirst {
	private SqlSessionFactory  sqlSessionFactory;
	@Before
	public void init() throws IOException{
		//创建会话工厂
		//配置文件
		String resource = "SqlMapConfig.xml";
		//加载配置文件到输入流中
		InputStream inputStream = Resources.getResourceAsStream(resource);
		//创建会话工厂
		sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
	}
	/**
	 * 根据id查询 只会返回一条记录
	 * selectOne只能用于返回一条记录，否则抛异常
	 */
	@Test
	public void findUserById(){
		//通过sqlSessionFactory来创建sqlSession
		SqlSession sqlSession = sqlSessionFactory.openSession();
		//通过sqlsession操作数据库
		User user = sqlSession.selectOne("test.findUserById", 1);
		//关闭sqlsession
		sqlSession.close();
		System.out.println(user.toString());
	}
	@Test
	public void findUserByName(){
		SqlSession sqlSession = sqlSessionFactory.openSession();
		List userList=sqlSession.selectList("test.findUserByName", "小明");
//		Iterator iterator = userList.iterator();
		System.out.println(userList.get(0).getUsername());
		for(User user:userList){
			System.out.println(user);
		}
//		while(iterator.hasNext()){
//			System.out.println(iterator.next());
//		}
	}
}

一个简单的mybatis入门程序-查询一条/多条记录