实体类package cn.liwen.entity;public class User {    private long id; //主键    private String username;//用户名    private String password;//密码    public long getId() {        return id;    }    public void setId(long 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;    }    @Override    public String toString() {        return "User{" +                "id=" + id +                ", username='" + username + '\'' +                ", password='" + password + '\'' +                '}';    }}

接口实现类package cn.liwen.impl;import cn.liwen.entity.User;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.testng.annotations.Test;import org.testng.annotations.BeforeClass;import java.io.IOException;import java.io.InputStream;import java.util.HashMap;import java.util.List;import java.util.Map;public class UserDaoImpl {    private SqlSession session = null;    @BeforeClass    public void init() throws IOException {        // 1、启动mybatis框架        // SqlSession--->SqlSessionFatory----->SqlSessionFatoryBuilder        SqlSessionFactoryBuilder ssb = new SqlSessionFactoryBuilder();        // 将mybatis.xml文件转化成流        InputStream ins = Resources.getResourceAsStream("mybatis.xml");        SqlSessionFactory ssf = ssb.build(ins);        session = ssf.openSession();    }    /**     * 查询所以名字     * */    @Test    public void getAllUser()  {        /** 2、调用局部配置文件中的sql语句*/        List userList = session.selectList("cn.liwen.impl.UserDaoImpl.getAllUser");        for (User user : userList) {            System.out.println(user);        }    }    /**使用lists方式*/    @Test    public void getAllUserlist() throws IOException {        List userList = session.selectList("cn.liwen.impl.UserDaoImpl.getAllUserlist");        for (User user : userList) {            System.out.println(user);        }    }    /**使用map方式*/    @Test    public void getAllUser2()  {        // 2、调用局部配置文件中的sql语句        List> userList = session.selectList("cn.liwen.impl.UserDaoImpl.getAllUser2");        for (Map map : userList) {            System.out.println(map);        }    }    /**测试单条记录方式*/    @Test    public void getUserById() {        //带参数方式        long id = 1L;        Map userList = session.selectOne("cn.liwen.impl.UserDaoImpl.getUserById",id);            System.out.println(userList);    }    /**多个参数*/    @Test    public void getUserByCondition() {        Map paraMap =  new HashMap();        paraMap.put("username","李玟");        paraMap.put("pwd","321321");        Map userList = session.selectOne("cn.liwen.impl.UserDaoImpl.getUserById",paraMap);        System.out.println(userList);    }    /**通过实体类方式取值*/    @Test    public void getUserByCondition2() {        // 同时传递多个参数        User user = new User();        user.setUsername("李玟");        user.setPassword("321321");        Map userMap = session.selectOne("cn.liwen.impl.UserDaoImpl.getUserByCondition2", user);        System.out.println(userMap);    }     /**    执行模糊查询     */     @Test     public void getUserByMh()     {         // 传递参数         Map paramMap = new HashMap();         paramMap.put("password", "3");         List> userMap = session.selectList("cn.liwen.impl.UserDaoImpl.getUserByMh", paramMap);         for (Map map : userMap) {             System.out.println(map);         }     }     /**添加数据    delete、insert、update标签没有resultType属性     */    @Test    public void addUser()    {        Map paramMap = new HashMap();        paramMap.put("username","北京");        paramMap.put("password","123455");        int flag = session.insert("cn.liwen.impl.UserDaoImpl.addUser", paramMap);        //增删改必须提交事务        session.commit();        System.out.println(flag);    }}

接口实现类.xml<?xml  version="1.0" encoding="UTF-8"?>mapper        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">                        SELECT * FROM users                    SELECT * FROM users                    SELECT * FROM users                    SELECT * FROM users where id=#{id}                    SELECT * FROM users WHERE username=#{username} AND PASSWORD=#{pwd}                    SELECT * FROM users WHERE username=#{username} AND PASSWORD=#{password}                    SELECT * FROM users WHERE PASSWORD LIKE CONCAT('%',#{password},'%')                    INSERT INTO users SET username=#{username},PASSWORD=#{password}

mybatis.xml文件<?xml  version="1.0" encoding="UTF-8"?>configuration        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"        "http://mybatis.org/dtd/mybatis-3-config.dtd">