mybatis 之四:mybatis整合spring

前言

整合思路：
1、数据源信息交给spring管理
2、sqlsessionfactory交给spring进行单例管理
3、由spring来管理mapper代理的代理类

下面以根据用户id查询用户信息案例来搭建工程
步骤一：建立java工程

步骤二：添加整合包（这里需要的jar包过多）
Mysql的驱动包
Mybatis的核心包和依赖包
Mybatis和spring的整合包
Spring的包
dbcp数据库连接池包
等等

步骤三：在src目录下建立sqlmapconfig.xml配置文件，里面暂时只有一个dtd文件声明

<?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>

</configuration>

步骤四：在src目录下建立applicationcontext.xml配置文件
里面目前只配置一些重要连接数据库的信息，后面步骤将加入重要信息

<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:mvc="http://www.springframework.org/schema/mvc"
	xmlns:context="http://www.springframework.org/schema/context"
	xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"
	xsi:schemaLocation="http://www.springframework.org/schema/beans 
		http://www.springframework.org/schema/beans/spring-beans-3.2.xsd 
		http://www.springframework.org/schema/mvc 
		http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd 
		http://www.springframework.org/schema/context 
		http://www.springframework.org/schema/context/spring-context-3.2.xsd 
		http://www.springframework.org/schema/aop 
		http://www.springframework.org/schema/aop/spring-aop-3.2.xsd 
		http://www.springframework.org/schema/tx 
		http://www.springframework.org/schema/tx/spring-tx-3.2.xsd ">

	

	<!-- 创建数据源 -->
	<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource">
		<property name="driverClassName" value="com.mysql.jdbc.Driver" />
		<property name="url" value="jdbc:mysql://localhost:9806/sshe" />
		<property name="username" value="root" />
		<property name="password" value="root" />
		<property name="maxActive" value="10" />
		<property name="maxIdle" value="5" />
	</bean>

	<!-- SqlSessionFactory -->
	<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
		<!-- 指定mybatis的全局配置文件的路径 -->
		<property name="configLocation" value="SqlMapConfig.xml"></property>
		<!-- 数据源 -->
		<property name="dataSource" ref="dataSource"></property>
	</bean>
</beans>

步骤五：创建pojo类

public class User {
private int age;
private int id;
private String name;
此处省略set与get方法。。
}

步骤六：创建mapper代理
首先是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="com.zwl.mapper.UserMapper">
	<!-- 根据用户ID查询用户信息 -->
	<select id="findUserById" parameterType="int" resultType="com.zwl.pojo.User">
		SELECT
		* FROM user WHERE id =#{id}
	</select>
</mapper>

接下来是mapper接口

public interface UserMapper {
	public User findUserById(int id) throws Exception;
}

然后在sqlmapconfig.xml文件中声明代理文件

<configuration>
	<!-- 加载映射文件 -->
	<mappers>
		<mapper resource="com/zwl/mapper/UserMapper.xml" />
	</mappers>
</configuration>

步骤七：spring中注入

<bean id="UserMapper" class="org.mybatis.spring.mapper.MapperFactoryBean">
		<!-- 设置代理类的接口 -->
		<property name="mapperInterface" value="com.zwl.mapper.UserMapper"></property>
		<!-- 依赖注入SqlSessionFactory -->
		<property name="sqlSessionFactory" ref="sqlSessionFactory"></property>
	</bean>

步骤八：测试类

public class test {
	private ApplicationContext ctx;

//在测试之前自动加载
	@Before
	public void setUp() throws Exception {
		ctx = new ClassPathXmlApplicationContext(
				"applicationContext.xml");
	}
	
	@Test
	public void testFindUserById() throws Exception {
		
		UserMapper dao = (UserMapper) ctx.getBean("userMapper");
		
		User user = dao.findUserById(1);
		
		System.out.println(user.getName());
	}
}

测试结果：取出数据库中的helloworld
至此mybatis整合spring完成