Mybatis 第一个例子

configuration.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>
  
  <!-- 环境元素定义了如何配置环境 -->
  <environments default="development">
    <environment id="development">
      
      <!-- 事务管理器 ==在 MyBatis 中有两种类型的事务管理器（也就是 type=”[JDBC|MANAGED]”）
      JDBC – 这个配置就是直接使用了 JDBC 的提交和回滚设置，它依赖于从数据源得到的连接来管理事务范围。
      Note: 如果你正在使用 Spring + MyBatis，则没有必要配置事务管理器，因为 Spring 模块会使用自带的管理器来覆盖前面的配置。
      -->
      <transactionManager type="JDBC"/>
      
      <!-- dataSource 元素使用基本的 JDBC 数据源接口来配置 JDBC 连接对象的资源。 -->
      <dataSource type="POOLED">
        <property name="driver" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:3306/test"/>
        <property name="username" value="root"/>
        <property name="password" value="123456"/>
      </dataSource>
    </environment>
  </environments>
  
  <mappers>
    <mapper resource="userMapper.xml"/>
  </mappers>
</configuration>

User.java

package com.test.bean;

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
                + "]";
    }
}

user.sql

-- --------------------------------------------------------
-- Host:                         127.0.0.1
-- Server version:               5.6.15-enterprise-commercial-advanced - MySQL Enterprise Server - Advanced Edition (Commercial)
-- Server OS:                    Win64
-- HeidiSQL Version:             8.0.0.4396
-- --------------------------------------------------------

/*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */;
/*!40101 SET NAMES utf8 */;
/*!40014 SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0 */;
/*!40101 SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='NO_AUTO_VALUE_ON_ZERO' */;

-- Dumping structure for table test.user
DROP TABLE IF EXISTS `user`;
CREATE TABLE IF NOT EXISTS `user` (
  `id` int(10) NOT NULL AUTO_INCREMENT,
  `name` varchar(50) NOT NULL,
  `password` varchar(32) NOT NULL,
  `email` varchar(32) NOT NULL,
  `mobile` varchar(32) NOT NULL,
  `status` tinyint(4) NOT NULL,
  `createtime` datetime NOT NULL,
  `changetime` datetime NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=4 DEFAULT CHARSET=utf8;

-- Dumping data for table test.user: ~3 rows (approximately)
DELETE FROM `user`;
/*!40000 ALTER TABLE `user` DISABLE KEYS */;
INSERT INTO `user` (`id`, `name`, `password`, `email`, `mobile`, `status`, `createtime`, `changetime`) VALUES
	(1, 'admin', 'admin', 'admin@test.com', '12312341234', 1, '2015-02-07 13:29:52', '2015-02-07 13:29:53'),
	(2, 'zhangsan', 'zhangsan', 'zhangsan@test.com', '12312341234', 1, '2015-02-07 13:34:45', '2015-02-07 13:34:45'),
	(3, 'lisi', 'lisi', 'lisi@test.com', '12312341234', 1, '2015-02-07 13:45:58', '2015-02-07 13:45:59');
/*!40000 ALTER TABLE `user` ENABLE KEYS */;
/*!40101 SET SQL_MODE=IFNULL(@OLD_SQL_MODE, '') */;
/*!40014 SET FOREIGN_KEY_CHECKS=IF(@OLD_FOREIGN_KEY_CHECKS IS NULL, 1, @OLD_FOREIGN_KEY_CHECKS) */;
/*!40101 SET CHARACTER_SET_CLIENT=@OLD_CHARACTER_SET_CLIENT */;

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="User">
  <select id="listUser" resultType="com.test.bean.User">
    select id, name, password
    from user
  </select>
</mapper>

UserTest.java

package com.test.dao.mybatis;

import java.io.IOException;
import java.io.Reader;
import java.util.List;

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 org.junit.Test;

import com.test.bean.User;

public class UserTest {
    /**
     * 获得MyBatis SqlSessionFactory
     * SqlSessionFactory负责创建SqlSession，一旦创建成功，就可以用SqlSession实例来执行映射语句
     * ，commit，rollback，close等方法。
     * 
     * @return
     */
    private static SqlSessionFactory getSessionFactory() {
        SqlSessionFactory sessionFactory = null;
        String resource = "configuration.xml";
        try {
            Reader reader = Resources.getResourceAsReader(resource);
            sessionFactory = new SqlSessionFactoryBuilder().build(reader);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return sessionFactory;
    }
    
    @Test
    public void test() {
        SqlSession sqlSession = getSessionFactory().openSession();
        List<User> users = sqlSession.selectList("User.listUser");
        for (User u: users) {
            System.out.println(u);
        }
    }
}