mybatis的增删改查

一、配置文件方式

 mapper.xml:

<?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">
<mapper namespace="com.hy.mybatis.test.News">
    
    
    <insert id="insertNews" parameterType="com.hy.mybatis.test.News">
        insert into news(title,content,author,createdate) values(#{title},#{content},#{author},#{createdate})
    </insert>
    
    <delete id="deleteNews" parameterType="int">
        delete from news where id= #{id}
    </delete>
    
    <update id="updateNews" parameterType="com.hy.mybatis.test.News">
        update news set author = #{author} where id = #{id}
    </update>
    
    <select id="getAllNews" resultType="com.hy.mybatis.test.News">
        select * from news
    </select>
    
    <select id="getNews" parameterType="int" resultType="com.hy.mybatis.test.News">
        select * from news where id=#{id}
    </select>
</mapper>

引入：

<mappers>
        <mapper resource="com/hy/mybatis/test/News.xml"/>
    </mappers>

测试：

public static SqlSession getSqlSession() {
        InputStream is = MyBatisUtil.class.getClassLoader().getResourceAsStream("mybatis.xml");
        SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is);
        return factory.openSession(true);
    }

封装获取sqlSession的方法，这里采用自动提交事务的方式。

@Test
    public void testAddNews() {
        SqlSession session = MyBatisUtil.getSqlSession();
        String statement = "com.hy.mybatis.test.News.insertNews";
        int insert = session.insert(statement, new News(-1, "android学习", "学习",
                "李博", new Date()));
        System.out.println(insert);
    }

    @Test
    public void testDeleteNews() {
        SqlSession session = MyBatisUtil.getSqlSession();
        String statement = "com.hy.mybatis.test.News.deleteNews";
        int delete = session.delete(statement, 2);
        System.out.println(delete);
    }

    @Test
    public void testUpdateNews() {
        SqlSession session = MyBatisUtil.getSqlSession();
        String statement = "com.hy.mybatis.test.News.updateNews";
        int update = session.update(statement, new News(3, "", "", "xx",
                new Date()));
        System.out.println(update);
    }

    @Test
    public void testgetAllNews() {
        SqlSession session = MyBatisUtil.getSqlSession();
        String statement = "com.hy.mybatis.test.News.getAllNews";
        List<News> list = session.selectList(statement);
        System.out.println(list);
    }

 

二、注解方式

 写一个mapperInterface:

package com.hy.mybatis.test;

import java.util.List;

import org.apache.ibatis.annotations.Delete;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.Update;

public interface NewsInterface {
    
    @Insert("insert into news(title,content,author,createdate) values(#{title},#{content},#{author},#{createdate})")
    public int add(News news);
    
    @Delete("delete from news where id= #{id}")
    public int deleteById(int id);
    
    @Update("update news set author = #{author} where id = #{id}")
    public int update(News news);
    
    @Select("select * from news")
    public List<News> getAllNews();
    
}

测试代码：

@Test
    public void testAddNews2() {
        SqlSession session = MyBatisUtil.getSqlSession();
        NewsInterface newsInterface= session.getMapper(NewsInterface.class);
        int add = newsInterface.add(new News(-1, "android学习", "学习",
                "李博", new Date()));
        System.out.println(add);
    }

先获取一个mapperInterface的示例，然后调用就行了！！