MyBatis增删改查

MyBatis 是一款优秀的持久层框架，它支持定制化 SQL、存储过程以及高级映射。MyBatis 避免了几乎所有的 JDBC 代码和手动设置参数以及获取结果集。MyBatis 可以使用简单的 XML 或注解来配置和映射原生信息，将接口和 Java 的 POJOs(Plain Old Java Objects,普通的 Java对象)映射成数据库中的记录。

在使用前要导入一下东西方便之后使用

练习时用的部分代码

Usermapper

<?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.bdqn.dao.Userdao">
  <!--  <select id="selectCount" resultType="int">
   select count(1) from user

   </select> -->
    <select id="selectUser" resultType="com.bdqn.entity.User"  >
    select  *  from user
    </select>

    <!-- //模糊查询 -->
    <select id="selectByUname" resultType="com.bdqn.entity.User" parameterType="String">
    select * from user where uname like concat ('%',#{uname},'%')
                                      <!-- //connat必须加 -->
    </select>



    <delete id="deleteUser" parameterType="int">
    delete from user where uid=#{uid}
    </delete>

    <update id="updateUser" parameterType="com.bdqn.entity.User">
    update user set uname=#{uname},upwd=#{upwd} where uid=#{uid}
    </update> 

    <insert id="addUser" parameterType="com.bdqn.entity.User">
    insert into user(uname,pwd) values {#{uname},#{upwd}}
    </insert>

</mapper>

text

package com.bdqn.text;

import java.io.IOException;
import java.io.InputStream;
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 com.bdqn.dao.Userdao;
import com.bdqn.entity.User;
import com.bdqn.utils.SqlSessionUtils;





public class Text {

    public static void main(String[] args) {
        InputStream is=null;
        SqlSession session =null;
        try {



            /*//删除
            session =SqlSessionUtils.getSqlSession();
            int count  =session.getMapper(Userdao.class).deleteUser(1);
            session.commit();
            System.out.println(count);*/

        /*  //添加
            session =SqlSessionUtils.getSqlSession();
            User user=new User();
            user.setUid(6);
            user.setUname("ggsimida");
            user.setUpwd("404");
            int count =session.getMapper(Userdao.class).addUser(user);
            session.commit();
            System.out.println(count);*/


            /*//查询
            session =SqlSessionUtils.getSqlSession();
            List<User> list =session.getMapper(Userdao.class).selectUser();
            for(User user:list ){
                System.out.println(user.toString());
            }*/


            /*      
            is=Resources.getResourceAsStream("mybatis-config.xml");
            SqlSessionFactory factory=new SqlSessionFactoryBuilder().build(is);
            SqlSession session =   factory.openSession();                
            int count=session.insert("com.bdqn.dao.UserMapper.xml");
            System.out.println(count);*/

        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            /*//事物回滚
            session.rollback();*/
        }finally{
            try {
                if (is !=null) {
                    is.close();
                }
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }

    }

}

utils

package com.bdqn.utils;

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

import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

public class SqlSessionUtils {
    private static SqlSessionFactory sqlSessionFactory;

    static{
    try {
        InputStream is =Resources.getResourceAsStream("mybatis-config.xml");
                sqlSessionFactory=new SqlSessionFactoryBuilder().build(is);
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }       
    }

    public  static SqlSession getSqlSession(){
        SqlSession sqlSession =sqlSessionFactory.openSession(false);
        return sqlSession;

    }

    public void closeSession(SqlSession sqlSession){
        if (sqlSession !=null) {
            sqlSession.close();
        }
    }
}

写的不是很好不懂欢迎私聊..