mybatis+spring整合入门

（一）导包

（二）配置文件+Java代码

（1）applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:context="http://www.springframework.org/schema/context" xmlns:p="http://www.springframework.org/schema/p"
	xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.0.xsd
	http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd
	http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
	http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.0.xsd">


	<context:property-placeholder location="classpath:db.properties"/>

<!-- 数据库连接池 -->
	<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"
		destroy-method="close">
		<property name="driverClassName" value="${jdbc.driver}" />
		<property name="url" value="${jdbc.url}" />
		<property name="username" value="${jdbc.username}" />
		<property name="password" value="${jdbc.password}" />
		<property name="maxActive" value="10" />
		<property name="maxIdle" value="5" />
	</bean>

<!-- mybatis的工厂 -->
<bean id="sqlSessionFactoryBean" class="org.mybatis.spring.SqlSessionFactoryBean">
	<property name="dataSource" ref="dataSource"></property>
<!-- mybatis核心配置文件的位置 -->
    <property name="configLocation" value="classpath:sqlMapConfig.xml"/>
</bean>

<!--  dao层的实例化 
<bean id="userDao" class="cn.shu.dao.UserDaoImpl">
	<property name="sqlSessionFactory" ref="sqlSessionFactoryBean"/>
</bean> -->


<!-- Mapper动态代理开发，Mapper类工厂 可以产生各种Mapper实例-->
<!-- 
SqlSeeion sqlSession = sqlSessionFactory.openSession()
UserMapper userMapper = sqlSession.getMapper(UserMapper.class) 
-->
<!-- <bean id="userMapper" class="org.mybatis.spring.mapper.MapperFactoryBean">
	需要sqlSessionFactory才能获得sqlSession
	<property name="sqlSessionFactory" ref="sqlSessionFactoryBean"/>
	有了sqlSession，还需要给接口才能使用getMapper方法获得实例
	<property name="mapperInterface" value="cn.shu.Mapper.UserMapper"></property>
</bean> -->

<!--若Mapper包下文件太多，类似上面注释的配置会非常多，重复， mapper动态开发，扫描，不需要注入工厂sqlSessionFactory,会自动寻找 -->
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
	<!-- 基本包 -->
	<property name="basePackage" value="cn.shu.Mapper"></property>
</bean>

</beans>

（2）db.properties

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/mybatis?characterEncoding=utf-8
jdbc.username=root
jdbc.password=123456

(3)sqlMapConfig.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>
	<typeAliases>
		<package name="cn.shu.pojo"/>
	</typeAliases>
<mappers>	
	  <package name="cn.shu.mapper"/> 
</mappers>
</configuration>

(4)log4j.xml

# Global logging configuration
log4j.rootLogger=DEBUG, stdout
# Console output...
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n

(5)UserMapper.java

package cn.shu.Mapper;

import cn.shu.pojo.User;

public interface UserMapper {
	
	public User selectUserById(Integer id); 
	
}

(6)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="cn.shu.Mapper.UserMapper">
	
	<select id="selectUserById" parameterType="Integer" resultType="cn.shu.pojo.User">
	  select * from user where id=#{v}
	</select>
</mapper>

(7)User.java 

省略

（3）测试代码

package cn.shu.junit;


import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import cn.shu.Mapper.UserMapper;
import cn.shu.pojo.User;

public class JunitTest {
	
	@Test
	public void test1() throws Exception {
		
		//读取配置文件
 ApplicationContext ac = new  ClassPathXmlApplicationContext("applicationContext.xml");
		/*获取bean两种方法
		 * 1.给接口ac.getBean(UserMapper.class)
		 * 2.给id（配置文件中）
		 * ac.getBean("userMapper")*/
         UserMapper mapper = (UserMapper) ac.getBean("userMapper");
         User u = mapper.selectUserById(10);
         System.out.println(u);
	}
	
	
	
	@Test
	public void test2() throws Exception {
		
		//读取配置文件
 ApplicationContext ac = new  ClassPathXmlApplicationContext("applicationContext.xml");
		/*获取bean两种方法
		 * 1.给接口ac.getBean(UserMapper.class)
		 * 2.给id（配置文件中，此时没有配置id，扫描Mapper会产生一堆mapper）
		 * ac.getBean("userMapper")*/
         UserMapper mapper = (UserMapper) ac.getBean(UserMapper.class);
         User u = mapper.selectUserById(16);
         System.out.println(u);
	}
}