1:导入mybatis jar包到maven中

<dependency>
    <groupId>org.mybatisgroupId>
    <artifactId>mybatisartifactId>
    <version>3.5.10version>
dependency>

2:把maven关键配置导入pom.xml中防止报错

    <build>
        
        <resources>
            <resource>
                
                <directory>src/main/javadirectory>
                <includes>
                    
                    
                    <include>**/*.propertiesinclude>
                    <include>**/*.xmlinclude>
                includes>
                
                <filtering>falsefiltering>
            resource>
            <resource>
                <directory>src/main/resourcesdirectory>
            resource>
        resources>
    build>

3:根据官网mybatis文档开始初始化操作

首先初始化maven项目结构

在java目录先新建3个文件包,分别是utils  pojo  mapper

新建MybatisUtils.class到utils包下

package com.terry.utils;

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 java.io.IOException;
import java.io.InputStream;

public class MybatisUtils {
    private static SqlSessionFactory sqlSessionFactory;

    static {
        try {
            String resource = "mybatis-config.xml";
            InputStream inputStream = Resources.getResourceAsStream(resource);
            sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public static SqlSession getSqlSession() {
        return sqlSessionFactory.openSession();
    }
}

新建mybatis-config.xml到resources目录下

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

    default="development">
        
            
            
                
                
                
                
            
        
    
    
        
    

新建一个实体类user到pojo包下,对应数据库中的user

package com.terry.pojo;

public class user {
    private int id;
    private String username;
    private String password;

    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;
    }
}

新建一个usermapper接口到mapper包下,接口中定义需要使用的数据库操作方法

package com.terry.mapper;

import com.terry.pojo.user;

import java.util.List;

public interface userMapper {
    //获取全部用户属性
    List getUserList();

    //根据用户id获取用户属性
    user getUserById(int id);

    //增加用户
    void InsertUser(user user);
    //根据id修改用户
    void updatauser(user user);
    //根据id删除用户
    void deleteuser(int id);
}

新建一个usermapper.xml到mapper包下

<?xml version="1.0" encoding="UTF-8" ?>
DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">

    
        select *
        from user
    
    
        select *
        from user
        where id = #{id}
    
    
        insert into user
        values (#{id}, #{username}, #{password})
    
    
        update user set username=#{username},password=#{password} where id=#{id}
    
    
        delete from user where id=#{id}
    

4:测试CURD代码

新建一个测试目录test

查询全部成员测试类SelectAllTest.class

import com.terry.mapper.userMapper;
import com.terry.pojo.user;
import com.terry.utils.MybatisUtils;
import org.apache.ibatis.session.SqlSession;
import org.junit.Test;

public class SelectAllTest {
    @Test
    public void test() {
        try (SqlSession sqlSession = MybatisUtils.getSqlSession()) {
            userMapper mapper = sqlSession.getMapper(userMapper.class);
            for (user user : mapper.getUserList()) {
                System.out.println(user.getId() + "\t" + user.getUsername() + "\t" + user.getPassword());
            }

        }
    }
}

根据id查询selectUserByid.class

import com.terry.mapper.userMapper;
import com.terry.pojo.user;
import com.terry.utils.MybatisUtils;
import org.apache.ibatis.session.SqlSession;
import org.junit.Test;

public class selectUserByid {
    @Test
    public void test() {
        try (SqlSession sqlSession = MybatisUtils.getSqlSession()) {
            userMapper mapper = sqlSession.getMapper(userMapper.class);
            user user = mapper.getUserById(3);
            System.out.println(user.getId() + "\t" + user.getUsername() + "\t" + user.getPassword());
        }
    }

}

根据id更新用户 updatauser.class

import com.terry.mapper.userMapper;
import com.terry.pojo.user;
import com.terry.utils.MybatisUtils;
import org.apache.ibatis.session.SqlSession;
import org.junit.Test;

public class updatauser {
    @Test
    public void test(){
        SqlSession sqlSession = MybatisUtils.getSqlSession();
        userMapper mapper = sqlSession.getMapper(userMapper.class);
        user u=new user();
        u.setId(1);
        u.setUsername("zzz");
        u.setPassword("zhang12340");
        mapper.updatauser(u);
        sqlSession.commit();
        sqlSession.close();
    }
}

根据id删除用户 deleteuser.clas

import com.terry.mapper.userMapper;
import com.terry.utils.MybatisUtils;
import org.apache.ibatis.session.SqlSession;
import org.junit.Test;

public class deleteuser {
    @Test
    public void test(){
        SqlSession sqlSession = MybatisUtils.getSqlSession();
        userMapper mapper = sqlSession.getMapper(userMapper.class);
        mapper.deleteuser(1);
        sqlSession.commit();
        sqlSession.close();
    }
}

插入用户操作 InsertUser.class

import com.terry.mapper.userMapper;
import com.terry.pojo.user;
import com.terry.utils.MybatisUtils;
import org.apache.ibatis.session.SqlSession;
import org.junit.Test;

public class InsertUser {
    @Test
    public void test() {
        user u = new user();
        u.setId(5);
        u.setUsername("java");
        u.setPassword("zhang12345");
        try (SqlSession sqlSession = MybatisUtils.getSqlSession()) {
            userMapper mapper = sqlSession.getMapper(userMapper.class);
            mapper.InsertUser(u);
            sqlSession.commit();
            sqlSession.close();
        }

    }
}