mybatis简单示例

 

1、引入mybatis.jar mysql-connector-java-5.1.47.jar

<dependency>
    <groupid>org.mybatis</groupid>
    <artifactid>mybatis</artifactid>
    <version>3.4.6</version>
</dependency>

<!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
<dependency>
    <groupid>mysql</groupid>
    <artifactid>mysql-connector-java</artifactid>
    <version>5.1.47</version>
</dependency>

2、新增数据库资源文件datasource.properties

jdbc.driver=com.mysql.jdbc.driver
jdbc.url=jdbc:mysql://localhost:3306/test?useunicode=true&characterencoding=utf-8
jdbc.username=root
jdbc.password=

3、新增mybatis.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>
    <properties resource="datasource.properties"/>
    <environments default="dev">
        <environment id="dev">
            <transactionmanager type="jdbc"></transactionmanager>
            <datasource type="pooled">
                <property name="driver" value="${jdbc.driver}" />
                <property name="url" value="${jdbc.url}" />
                <property name="username" value="${jdbc.username}" />
                <property name="password" value="${jdbc.password}" />
            </datasource>
        </environment>
    </environments>
    <mappers>
        <mapper resource="mapper/usermapper.xml"/>
    </mappers>
</configuration>

4、新增userdomain.java

package cn.scp.mybatis.native_mybatis.domain;

import lombok.data;

import java.util.date;

@data
public class userdomain {
    private int id;
    private string name;
    private int age;
    private string idcard;
    private string school;
    private string job;
    private string remark;
    private date createdate;
    private date modifydate;
    private int deleteflag;
}

5、新增usermapper.java

package cn.scp.mybatis.native_mybatis.mapper;

import cn.scp.mybatis.native_mybatis.domain.userdomain;

/**
 * @description
 * @date 2019/3/17 10:30
 */
public interface usermapper {
    public userdomain selectbyid(int id);
}

6、新增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.scp.mybatis.native_mybatis.mapper.usermapper">
    <select id="selectbyid" resulttype="cn.scp.mybatis.native_mybatis.domain.userdomain">
        select * from t_user_info where id=#{id}
    </select>
</mapper>

7、新增mybatis工具类mybatisutil.java

package cn.scp.mybatis.native_mybatis.util;

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.reader;

public class mybatisutil {
    public static sqlsessionfactory sessionfactory;
    static {
        try{
            reader reader = resources.getresourceasreader("mybatis.xml");
            sessionfactory = new sqlsessionfactorybuilder().build(reader);
        }
        catch (exception e){
            system.out.println(e);
        }
    }

    public static sqlsession getsession(){
        return sessionfactory.opensession();
    }
}

8、测试

package cn.scp.mybatis.native_mybatis;

import cn.scp.mybatis.native_mybatis.domain.userdomain;
import cn.scp.mybatis.native_mybatis.mapper.usermapper;
import cn.scp.mybatis.native_mybatis.util.mybatisutil;
import org.apache.ibatis.session.sqlsession;

public class main {
    public static void main(string[] args) {
        sqlsession session = mybatisutil.getsession();
        usermapper usermapper = session.getmapper(usermapper.class);
        try{
            userdomain userdomain = usermapper.selectbyid(8);
            system.out.println(userdomain);
        }
        catch (exception e){
            system.out.println(e);
        }
    }
}

结果：

userdomain(id=8, name=7, age=11, idcard=null, school=鱼小学, job=null, remark=null, createdate=null, modifydate=null, deleteflag=0)