Mybatis配置-简单的使用

导包

基本配置

配置mybatis.config.xml文档

<?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"/>
        <dataSource type="POOLED">
            <property name="driver" value="com.mysql.jdbc.Driver"/>
            <property name="url" value="jdbc:mysql://localhost:3306/mybatis1"/>
            <property name="username" value="root"/>
            <property name="password" value="root"/>
        </dataSource>
        </environment>
    </environments>

<mappers>
　　<mapper resource="cn/zys/entity/user-mapper.xml"/>
</mappers>

</configuration>

 MyBatisUtils.java

package cn.zys.until;

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 MyBatisUtils {
    public static SqlSessionFactory getSqlSessionFactory() throws IOException{
        String resource = "mybatis.config.xml";
        InputStream inputStream = Resources.getResourceAsStream(resource);
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        return sqlSessionFactory;
    }

    public static SqlSession getSqlSession() throws IOException{
        SqlSessionFactory sqlSessionFactory = getSqlSessionFactory();
        return sqlSessionFactory.openSession();
    }
}

user-mapper.xml      注意xml命名和命名空间的格式对应

<?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.zys.entity.UserMapper">
    <select id="selectUser" resultType="cn.zys.entity.User">
        select name from user where id = #{id}
    </select>
</mapper>

User.java

package cn.zys.entity;

public class User {
    private int id;
    private String name;
    private String pwd;
    //
    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 getPwd() {
        return pwd;
    }
    public void setPwd(String pwd) {
        this.pwd = pwd;
    }
    @Override
    public String toString() {
        return "User [id=" + id + ", name=" + name + ", pwd=" + pwd + "]";
    }
}

test.java  

package cn.zys.test;

import java.io.IOException;

import org.apache.ibatis.session.SqlSession;

import cn.zys.entity.User;
import cn.zys.until.MyBatisUtils;

public class test {
    public static void main(String[] args) throws IOException {
        SqlSession sqlsession = MyBatisUtils.getSqlSession();
        User user = sqlsession.selectOne("cn.zys.entity.UserMapper.selectUser", 1); 此处命名空间加   id
        System.out.println(user.toString());
        sqlsession.close();
    }
}

运行结果