mybatis配置方法

首先导入mybatis-3.1.1.jar包以及Mysql-connector-java-5.1.6-bin.jar包

新建一个数据库

create database mybatis;
use mybatis;
CREATE TABLE users(id INT PRIMARY KEY AUTO_INCREMENT, NAME VARCHAR(20), age INT);
INSERT INTO users(NAME, age) VALUES('Tom', 12);
INSERT INTO users(NAME, age) VALUES('Jack', 11);

然后建立Pojo文件

package test;

public class User {
    private int id;
    private String name;
    private int age;
    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 int getAge() {
        return age;
    }
    public User(){
        super();
    }
    public User(int id, String name, int age) {
        super();
        this.id = id;
        this.name = name;
        this.age = age;
    }
    public void setAge(int age) {
        this.age = age;
    }
    @Override
    public String toString() {
        return "User [id=" + id + ", name=" + name + ", age=" + age + "]";
    }
}

建立个映射文件userMapper.xml在同一个包test下

parameterType：需要的数据类型

resultType：返回的值类型

<?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="test.userMapper">
    <select id="getUser" parameterType="int" resultType="test.User">
        select * from users where id=#{id}
    </select>
</mapper>

然后新建conf.xml文件，在其中注册映射文件

<?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/mybatis" />
                <property name="username" value="root" />
                <property name="password" value="123456" />
            </dataSource>
        </environment>
    </environments>

    <mappers>
        <mapper resource="test/userMapper.xml"/>
    </mappers>
</configuration>

然后测试文件

package test;

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

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

public class Test {
    public static void main(String[] args) throws IOException {
        String resource = "conf.xml";
        InputStream is = Test.class.getClassLoader().getResourceAsStream(resource);
        SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is);
        SqlSession session = factory.openSession();
        String statement = "test.userMapper.getUser";
        User user = session.selectOne(statement, 2);
        System.out.println(user);
    }
}