MyBatis 插入时返回刚插入记录的主键值

MyBatis 插入时返回刚插入记录的主键值

一、要求：

1、数据库表中的主键是自增长的，如：id；

2、获取刚刚插入的记录的id值；

二、源代码：

1、User.java

package cn.com.zfc.model;

public class User {

    private Integer id;
    private String name;
    private String password;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    @Override
    public String toString() {
        return "User [id=" + id + ", name=" + name + ", password=" + password + "]";
    }

}

2、UserMapper.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="cn.com.zfc.model.UserMapper">

    <!-- 插入一条记录开始，返回主键插入记录的id -->
    <insert id="insert" parameterType="cn.com.zfc.model.User">
        insert into user
        (name,password)
        values
        (#{name},#{password})
        <!-- 
            selectKey中order属性的值是不同的，BEFORE先选择主键，设置keyProperty的值然后执行插入语句。
             AFTER是先执行插入语句，然后执行selectKey。 
         -->
        <selectKey keyColumn="id" keyProperty="id" order="AFTER"
            resultType="Integer">
            SELECT LAST_INSERT_ID() AS id
        </selectKey>
    </insert>
    <!-- 插入一条记录结束 -->
</mapper>

3、mybatis-config.xml

<?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>
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC" />
            <!-- 配置数据源 -->
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.jdbc.Driver" />
                <property name="url" value="jdbc:mysql://localhost:3306/mybatis_07" />
                <property name="username" value="root" />
                <property name="password" value="root" />
            </dataSource>
        </environment>
    </environments>
    <!-- 注册映射文件 -->
    <mappers>
        <!-- 注册映射文件，xml：resource -->
        <mapper resource="cn/com/zfc/model/UserMapper.xml" />
    </mappers>
</configuration>

4、MyBatisUtil.java

package cn.com.zfc.util;

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

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

public class MyBatisUtil {

    private static SqlSessionFactoryBuilder sqlSessionFactoryBuilder = null;
    private static SqlSessionFactory sessionFactory = null;
    private static InputStream inputStream = null;

    static {
        try {
            // 加载mybatis主配置文件
            inputStream = Resources.getResourceAsStream("mybatis-config.xml");
            sqlSessionFactoryBuilder = new SqlSessionFactoryBuilder();
            // 获取SqlSessionFactory对象
            sessionFactory = sqlSessionFactoryBuilder.build(inputStream);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    /**
     * 获取SqlSessionFactory对象
     * 
     * @return
     */
    public static SqlSessionFactory getSqlSessionFactory() {
        return sessionFactory;
    }
}

5、MyBatisTest.java

package cn.com.zfc.test;

import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;

import cn.com.zfc.model.User;
import cn.com.zfc.util.MyBatisUtil;

/**
 * 获取刚插入数据库表中记录的自增长主键
 * 
 * @title MyBatisTest
 * @describe
 * @author 张富昌
 * @date 2017年8月22日下午10:56:58
 */
public class MyBatisTest {
    public static void main(String[] args) {

        // 1、获取SqlSessionFactory
        SqlSessionFactory sqlSessionFactory = MyBatisUtil.getSqlSessionFactory();
        // 2、获取SqlSession
        SqlSession sqlSession = sqlSessionFactory.openSession();
        String statement = "cn.com.zfc.model.UserMapper.insert";
        User user = new User();
        user.setName("张富昌2");
        user.setPassword("123456");
        // 执行添加操作之后返回的结果
        int result = sqlSession.insert(statement, user);
        // 提交
        sqlSession.commit();
        // 关闭
        sqlSession.close();
        System.out.println("result:" + result);
        // 获取刚刚添加进去的自增长主键id
        System.out.println("id:" + user.getId());
    }
}

 三、运行效果