Mybatis是一款优秀的开源持久层框架。

入门demo

第一步：下载mybatis的jar包，github下载地址https://github.com/mybatis/mybatis-3
解压，把mybatis-3.3.0.jar，以及lib下的所有jar,额外引入mysql的驱动包到Eclipse的lib目录，并加入到classpath中。
Mybatis入门学习（一）_mybatis

第二步：新建数据库表，建立mybatis数据库，表student,字段id,name,age。

Mybatis入门学习（一）_数据库_02

第三步：新建Student实体类，加入log4j的配置文件。
Student.java文件

package com.hbk.pojo;

public class Student {

    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;
    }


}

log4j.properties文件

log4j.rootLogger=DEBUG,Console

#Console
log4j.appender.Console=org.apache.log4j.ConsoleAppender
log4j.appender.Console.layout=org.apache.log4j.PatternLayout
log4j.appender.Console.layout.ConversionPattern=%d [%t] %-5p [%c] - %m%n

log4j.logger.java.sql.ResultSet=INFO
log4j.logger.org.apache=INFO
log4j.logger.java.sql.Connection=DEBUG
log4j.logger.java.sql.Statement=DEBUG
log4j.logger.java.sql.PreparedStatement=DEBUG

第四步：新建mybatis的配置文件和student的mapper文件
mybatis-config.xml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"></transactionManager>
            <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="com/hbk/map/student.xml"/>
    </mappers>
</configuration>

student.xml文件：

<?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="com.hbk.mybatis.Student">
    <select id="findById" resultType="com.hbk.pojo.Student">
        select * from student where id = #{id}
    </select>
</mapper>

第五步：测试类：

package com.hbk.test;

import java.io.IOException;
import java.io.Reader;

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.hbk.pojo.Student;

public class StudentTest {

    public static void main(String[] args) {
        String resource = "com/hbk/map/mybatis-config.xml";
        try {
            Reader reader = Resources.getResourceAsReader(resource);
            SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(reader);
            SqlSession sqlSession = sqlSessionFactory.openSession();
            Student student = sqlSession.selectOne("findById", 1);
            System.out.println(student.getName());
            sqlSession.close();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }

}

输出结果：

Mybatis入门学习（一）_代码_03

工程目录结构图：

Mybatis入门学习（一）_mybatis_04