mybatis无接口直接调用xml的helloworld

1、首先在库里面创建一张表，sql语句如下：

CREATE TABLE `users` (
   `id` INT(11) NOT NULL AUTO_INCREMENT,
   `name` VARCHAR(20) COLLATE utf8_bin DEFAULT NULL,
   `age` INT(11) DEFAULT NULL,
   PRIMARY KEY (`id`)
 );
insert  into `users`(`id`,`name`,`age`) values (1,‘tome‘,12),(2,‘jack‘,11);

2、新建一个普通的java项目，将mybatis-3.2.8.jar、mysql-jdbc.jar添加到项目中。
3、新建与表名对应的实体类，具体代码如下：

public class Users {

    private Integer id;
    private String name;
    private Integer age;

    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 Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }

}

4、编写操作数据库的xml，具体如下：

<?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="IUserMapper">
    <select id="findById" parameterType="int" resultType="com.evan.pojo.Users">
        select *
        from users where id=#{id}
    </select>
</mapper>    

5、编写mybatis配置文件，具体如下：

<?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>
    <!--数据源配置 这块用 mysql数据库 -->
    <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/mybatishelloworld" />
                <property name="username" value="root" />
                <property name="password" value="123456" />
            </dataSource>
        </environment>
    </environments>
    <mappers>
        <!--userMapper.xml装载进来 同等于把“dao”的实现装载进来 -->
        <mapper resource="com/evan/dao/IUserMapper.xml" />
    </mappers>
</configuration> 

6、测试类内容如下：

package com.evan;

import java.io.IOException;

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 com.evan.pojo.Users;

public class MybatisHelloWorldTest {

    public static void main(String[] args) throws IOException {
        String resource = "mybatisConfig.xml";

        SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder()
                .build(Resources.getResourceAsReader(resource));

        SqlSession session = sessionFactory.openSession();

        Users user = session.selectOne("IUserMapper.findById", 1);

        System.out.println(user);
    }

}

7、项目目录截图如下：

8、项目源码下载地址（免积分）：http://download.csdn.net/download/zl544434558/8575601

9、mybatis的需要声明接口的helloworld博文地址：
http://blog.csdn.net/zl544434558/article/details/12620941