整合思路
需要spring通过单利方式管理sqlSessionFactory
spring和mybatis整合生成代理对象，使用sqlSessionFactory创建sqlsession（自动完成）
持久层mapper需要有spring进行管理
创建新工程
jar包：
mybatis3.2.7
spring3.2.0
mybatis-spring-1.2.2（mybatis和spring的整合包）
工程结构
Spring配置文件：
在classpath下创建applicationContext.xml，定义数据库链接池、SqlSessionFactory
applicationContext.xml
<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 ">
<!-- 加载配置文件 -->
<context:property-placeholder location="classpath:db.properties" />
<!-- 数据源，使用dbcp
maxIdle，最大空闲数，数据库连接的最大空闲时间。超过空闲时间，数据库连
接将被标记为不可用，然后被释放。设为0表示无限制。
MaxActive，连接池的最大数据库连接数。设为0表示无限制。
maxWait ，最大建立连接等待时间。如果超过此时间将接到异常。设为-1表示
无限制
-->
<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>
<!-- sqlSessionFactory
在mybatis和spring的整合包中
-->
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<!-- 加载mybatis的配置文件 -->
<property name="configLocation" value="mybatis/SqlMapConfig.xml"/>
<!-- 数据源 -->
<property name="dataSource" ref="dataSource"/>
</bean>
<!-- 原始dao开发方法 -->
<bean id="userDao" class="cn.ztc.ssm.dao.UserDaoImpl">
<property name="sqlSessionFactory" ref="sqlSessionFactory"></property>
</bean>
</beans>```
Mybatis配置文件
在classpath下创建mybatis/SqlMapConfig.xml
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>
<settings>
<setting name="lazyLoadingEnabled" value="true"/>
<setting name="aggressiveLazyLoading" value="false"/>
<setting name="cacheEnabled" value="true"/>
</settings>
<typeAliases>
<!-- 批量别名的定义（常用）
name:指定包名，Mybatis会自动扫描包中的po类。自动定义别名，别名就是类名，首字母大写小写都可
-->
<package name="cn.ztc.ssm.po"/>
</typeAliases>
<!-- 加载映射文件 -->
<mappers>
<mapper resource="sqlmap/User.xml"/>
<!-- 批量加载
name:mapper接口的包名
-->
<package name="cn.ztc.ssm.mapper"/>
</mappers>
</configuration>
原始的Dao开发
Dao接口实现类继承SqlSessionDaoSupport
使用此种方法即原始dao开发方法，需要编写dao接口，dao接口实现类、映射文件
User.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="test">
<select id="findUserById" parameterType="int" resultType="cn.ztc.ssm.po.User">
select * from user where id = #{id}
</select>
</mapper>
UserDao.java
package cn.ztc.ssm.dao;
import cn.ztc.ssm.po.*;
public interface UserDao {
//根据id查用户信息
public User findUserById(int id) throws Exception;
}
UserDaoImpl.java
package cn.ztc.ssm.dao;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.support.SqlSessionDaoSupport;
import cn.ztc.ssm.po.*;
public class UserDaoImpl extends SqlSessionDaoSupport implements UserDao{
@Override
public User findUserById(int id) throws Exception {
//继承了SqlSessionDaoSupport，通过getSqlSession();方法得到sqlSession
SqlSession sqlSession = this.getSqlSession();
User user = sqlSession.selectOne("test.findUserById", id);
//方法结束，自动关闭sqlSession
//sqlSession.close();
return user;
}
}
测试类
package cn.ztc.ssm.dao;
import static org.junit.Assert.*;
import org.junit.Before;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import cn.ztc.ssm.po.User;
public class UserDaoImplTest {
private ApplicationContext applicationContext;
//在setUp方法中得到spring的容器
@Before
public void setUp() throws Exception{
applicationContext = new ClassPathXmlApplicationContext("classpath:spring/applicationContext.xml");
}
@Test
public void testFindUserById() throws Exception {
UserDao userDao = (UserDao) applicationContext.getBean("userDao");
User user = userDao.findUserById(1);
System.out.println(user);
}
}
mapper代理开发
UserMapper.java
package cn.ztc.ssm.mapper;
import java.util.List;
import cn.ztc.ssm.po.User;
import cn.ztc.ssm.po.UserCustom;
import cn.ztc.ssm.po.UserQueryVo;
public interface UserMapper {
//根据id查用户信息
public User findUserById(int id) throws Exception;
}
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.ztc.ssm.mapper.UserMapper">
<select id="findUserById" parameterType="int" resultType="cn.ztc.ssm.po.User">
select * from user where id = #{id}
</select>
</mapper>
applicationContext.xml添加
<bean id="userMapper" class="org.mybatis.spring.mapper.MapperFactoryBean">
<property name="mapperInterface" value="cn.ztc.ssm.mapper.UserMapper"></property>
<property name="sqlSessionFactory" ref="sqlSessionFactory"></property>
</bean>```
测试类
package cn.ztc.ssm.mapper;
import static org.junit.Assert.*;
import org.junit.Before;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import cn.ztc.ssm.po.User;
public class UserMapperTest {
private ApplicationContext applicationContext;
//在setUp方法中得到spring的容器
@Before
public void setUp() throws Exception{
applicationContext = new ClassPathXmlApplicationContext("classpath:spring/applicationContext.xml");
}
@Test
public void testFindUserById() throws Exception {
UserMapper usermapper = (UserMapper) applicationContext.getBean("userMapper");
User user = usermapper.findUserById(1);
System.out.println(user);
}
}
此方法问题：要针对每个mapper配置
解决方法：applicationContext.xml中添加
<!-- mapper批量扫描，从mapper包中扫描出mapper接口，自动创建代理对象并在spring容器中注册
自动扫描出来的mapper的bean的id为mapper类名，首字母小写
-->
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<!-- 指定扫描包名
如果扫描多个包，每个包中间使用半角逗号分隔
可删除sqlmapconfig.xml文件中的批量扫描配置
-->
<property name="basePackage" value="cn.ztc.ssm.mapper"/>
<property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
</bean>
```