Mybatis增删改查

主键返回

导入所需的包

 

创建工程并配置所需环境

<?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">
<configuration>
    <typeAliases>
        <typeAlias alias="User" type="com.tanlei.newer.pojo.User"></typeAlias>
    </typeAliases>
    
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC"></transactionManager>
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.jdbc.Driver"></property>
                <property name="url" value="jdbc:mysql://localhost:3306/test?useUnicode=true&amp;characterEncoding=utf8"></property>
                <property name="username" value="root"></property>
                <property name="password" value="password"></property>
            </dataSource>
        </environment>
    </environments>

    <mappers>
        <mapper resource="com/tanlei/newer/pojo/User.xml"></mapper>
    </mappers>
</configuration>

创建 Java 类和接口及xml映射文件

JAVA类

package com.tanlei.newer.pojo;

/**
 * @author:Mr.Tan
 * @Create:2018-10-31-16-05
 **/
public class User {
    private int id;
    private String name;
    private String dept;
    private String phone;
    private String website;

    public String getWebsite() {
        return website;
    }
    public void setWebsite(String website) {
        this.website = website;
    }
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getDept() {
        return dept;
    }
    public void setDept(String dept) {
        this.dept = dept;
    }
    public String getPhone() {
        return phone;
    }
    public void setPhone(String phone) {
        this.phone = phone;
    }


}　　

　接口类　

package com.tanlei.newer.pojo;

import java.util.List;

public interface IUser {
    //查找一个用户信息
    public User getUser(int id);

   //增加一个用户
    public void insertUser(User user);

    //删除一个用户
    public void deleteUser(int userid);

    //修改一个用户
    public void updateUser(User user);

    //查询所有用户
    public List<User>  getUserList();
}

　映射文件　

<?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="user">-->
<mapper namespace="com.tanlei.newer.pojo.IUser">
    <!--根据用户id查找一个用户信息-->
    <select id="getUser" parameterType="int" resultType="User">
        SELECT * FROM USER WHERE id=#{userId}
    </select>
    <!--添加一个用户-->
    <insert id="insertUser" parameterType="User">
        INSERT INTO USER(name,dept,phone,website) VALUES(#{name},#{dept},#{phone},#{website});
    </insert>
    <!--根据id删除一个用户-->
    <delete id="deleteUser" parameterType="int">
        DELETE FROM USER WHERE id = #{id}
    </delete>
    <!--修改用户信息-->
    <update id="updateUser" parameterType="User">
       UPDATE USER SET
        name=#{name},
        dept = #{dept},
        website = #{website},
        phone = #{phone}
        WHERE id =#{id}
    </update>
    <!--获取所有用户-->
    <select id="getUserList" resultType="User">
        SELECT * FROM USER
    </select>



</mapper>

　main启动类方法　

package com.tanlei.newer.test;

import com.tanlei.newer.pojo.IUser;
import com.tanlei.newer.pojo.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 java.io.IOException;
import java.io.Reader;

/**
 * @author:Mr.Tan
 * @Create:2018-10-31-16-39
 **/
public class main {
    private static Reader reader;
    private  static SqlSessionFactory sqlSessionFactory;

    static{
        try {
            reader= Resources.getResourceAsReader("config/Configure.xml");
            sqlSessionFactory=new SqlSessionFactoryBuilder().build(reader);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public  SqlSessionFactory getSession(){
        return  sqlSessionFactory;
    }


    public static void main(String[] args) {
        SqlSession sqlSession=sqlSessionFactory.openSession();
         /*//根据id查找单个用户信息
         User user = sqlSession.selectOne( "com.tanlei.newer.pojo.IUser.getUser",1);
          System.out.println(user.getName());*/
        /*添加一个用户
        insertUser();*/
        /*删除用户
        deleteUser();*/
        /*根据id修改用户信息
        updateUser(); */
        /*获取用户列表
        getUserList();*/
        sqlSession.close();;
    }

    //添加一个用户
    public  static  void insertUser(){
        // 获取Session连接
        SqlSession session = sqlSessionFactory.openSession();
        // 获取Mapper
        IUser userMapper = session.getMapper(IUser.class);
        // 执行插入
        User user = new User();
        user.setName("Google");
        user.setDept("Tech");
        user.setWebsite("http://www.google.com");
        user.setPhone("120");
        userMapper.insertUser(user);
        // 提交事务
        session.commit();
    }

    //删除用户
    public static void deleteUser(){
        // 获取Session连接
        SqlSession session = sqlSessionFactory.openSession();
        // 获取Mapper
        IUser iuser = session.getMapper(IUser.class);
        iuser.deleteUser(1);
        session.commit();
    }

    //根据id修改用户信息
    public static  void updateUser(){
        // 获取Session连接
        SqlSession session = sqlSessionFactory.openSession();
        // 获取Mapper
        IUser iuser = session.getMapper(IUser.class);
        User user=iuser.getUser(1);
        user.setName("谭磊");
        iuser.updateUser(user);
        session.commit();
    }

    //查找所有用户信息
    public static  void getUserList(){
        // 获取Session连接
        SqlSession session = sqlSessionFactory.openSession();
        // 获取Mapper
        IUser userMapper = session.getMapper(IUser.class);
        for(User user:userMapper.getUserList()){
            System.out.println(user.getName() );
        }
        session.commit();
    }
}