mybatis框架入门教程(mysql数据库)(一)

1.先去mybatis官网把mybatis的jar下载下来,我用的3.1.1版本。mybatis的jar和连接mysql数据库的jar都放进创建的java工程里面。

2.创建mybatis数据库与user表

3.创建如图所示的包及xml文件。

4.配置文件conf.xml(前两行的文档类型必须写不然会报错)

<?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>
<!-- 
	development : 开发模式
	work : 工作模式
 -->
	<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="" />
			</dataSource>
		</environment>
	</environments>
	
	<mappers>
	<!-- 写mapper所在的包的路径 -->
		<mapper resource="com/kpzc/test1/userMapper.xml"/>
	</mappers>
</configuration>

5.创建user的bean 

package com.kpzc.bean;

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 void setAge(int age) {
		this.age = age;
	}

	public User() {
		super();
	}

	public User(int id, String name, int age) {
		super();
		this.id = id;
		this.name = name;
		this.age = age;
	}

	@Override
	public String toString() {
		return "User [id=" + id + ", name=" + name + ", age=" + age + "]";
	}

}

 6.写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">
<!-- 一般写包的路径(不带.xml) -->
<mapper namespace="com.kpzc.test1.userMapper">
	<!-- 
		根据id查询得到一个user对象
		parameterType id的参数类型
		resultType 写bean对象
	 -->
	 <select id="getUser" parameterType="int" resultType="com.kpzc.bean.User">
	 	select * from users where id=#{id}
	 </select>	 
</mapper>

 7.最后写一个测试方法

package com.kpzc.test1;

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;
import com.kpzc.bean.User;

/*
 * @author kpzc
 */
public class Test {
	public static void main(String[] args) throws IOException {
		//加载mybatis的配置文件,也加载关联的映射文件
		String resource = "conf.xml"; 
		InputStream is = Test.class.getClassLoader().getResourceAsStream(resource);
		//构建SqlSession工厂
		SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is);
		//创建能执行映射文件中sql的SqlSession
		SqlSession session = factory.openSession();
		//映射sql标识字符串
		String statement = "com.kpzc.test1.userMapper.getUser";
		//执行查询返回一个指定的user
		User user = session.selectOne(statement,1);
		System.out.println(user);
	}
}

 8.运行结果

有什么不正之处欢迎大家之处,鄙人不胜感激。

 

posted @ 2017-09-17 21:37  --鲲鹏展翅--  阅读(277)  评论(0编辑  收藏  举报