MyBatis配置

主配置文件

<?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>
	
	<!-- 加载jdbc属性文件 -->
	<properties resource="jdbc.properties"></properties>
	
	<!-- 定义别名 ,用于查询返回值-->
	<typeAliases>
		<typeAlias type="com.bjpn.domain.Student" alias="student"/>
	</typeAliases>
	
	<!-- 配置数据库环境 -->
	<environments default="mysql">
		<environment id="mysql">
			<transactionManager type="jdbc"></transactionManager>

			<dataSource type="POOLED">
				<property name="driver" value="${driver}" />
				<property name="url" value="${url}" />
				<property name="username" value="${username}" />
				<property name="password" value="${password}" />
			</dataSource>
		</environment>
	</environments>
	
	<!-- 配置映射文件 -->
	<mappers>
		<mapper resource="com/bjpn/dao/studentDao.xml"/>
	</mappers>
	

</configuration>

sql映射文件

<?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="student">

	<insert id="insertStudent">
		insert into t_student(name,age) values(#{name},#{age})
	</insert>
	
	<delete id="deleteStudent">
		delete from t_student where id = #{id}
	</delete>
	
	<select id="selectStudent" resultType="student">
		select * from t_student
	</select>
	
	<select id="selectOneStudent" resultType="student">
		select * from t_student where id = #{id}
	</select>
	
	<update id="updateStudent">
		update t_student set name = #{name},age = #{age} where id = #{id}
	</update>
</mapper>

获得事务工具类

package com.bjpn.util;

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

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

public class SqlSessionUtil {

	private static SqlSessionFactory factory = null;
	private static ThreadLocal<SqlSession> local = new ThreadLocal<>();

	static {

		InputStream in = null;
		try {
			in = Resources.getResourceAsStream("mybatis.xml");
		} catch (IOException e) {
			e.printStackTrace();
		}
		factory = new SqlSessionFactoryBuilder().build(in);
	}
	

	public static SqlSession getSession() {

		SqlSession session = local.get();

		if (session == null) {
			// 开启手动提交的事务
			session = factory.openSession();
			local.set(session);
		}
		return session;
	}
	

	public static void close(SqlSession session) {
		if (session != null) {
			local.remove();
			session.close();
		}
	}
}

动态代理工具类

package com.bjpn.util;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;

import org.apache.ibatis.session.SqlSession;

public class ServiceProxyUtil implements InvocationHandler {

	private Object targetObj;
	
	//创建动态代理对象
	//参数1 目标对象的类加载器
	//参数2 目标对象的所有父接口的Class
	//参数3 某个InvocationHandler 的接口对象,作用是:通知虚拟机这个代理对象在执行方法时要调用哪个类中的invoke方法
	public Object newProxyObject(Object targetObj) {
		
		this.targetObj = targetObj;

		return Proxy.newProxyInstance(targetObj.getClass().getClassLoader(), targetObj.getClass().getInterfaces(),
				this);
	}
	
	/*
	 * 动态代理的通用代理方法,当代理对象调用任何一个方法时都会自动执行这个invoke方法.JVM完成自动调用这个方法
	 * 
	 * 参数1 代理对象的引用,注意:这个对象最好不要使用
	 * 参数2 目标方法的反射引用对象
	 * 参数3 执行目标方法时所需要的参数列表,如果目标方法没有参数那么这个数组的长度为0
	 * 返回值Object  为目标方法的返回值数据,如果目标方法返回值类型为void 那么这个方法应该返回 null
	 */
	@Override
	public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {

		Object result = null;

		SqlSession session = SqlSessionUtil.getSession();

		result = method.invoke(targetObj, args);

		session.commit();

		SqlSessionUtil.close(session);

		return result;
	}

}