MyBatis
整合Spring
实现
对于上述的原始方式整合SSM
框架,在业务层代码中存在一些弊端,常见的弊端有:
- 每次加载业务方法时都会加载一次
sqlMapConfig.xml
配置文件,也都会创建一次工厂,最终执行完毕,都会进行一次事务提交,我们可以根据Spring
的方式进行依赖的注入
业务层编写Service
接口实现类代码如下:
java
package com.jlc.service.impl;
import com.jlc.domain.Account;
import com.jlc.service.AccountService;
import java.util.List;
@Service("accountService")
public class AccountServiceImpl implements AccountService {
@Override
public void save(Account account) {
try {
InputStream resourceAsStream = Resources.getResourceAsStream("sqlMapConfig.xml");
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(resourceAsStream);
SqlSession sqlSession = sqlSessionFactory.openSession();
AccountMapper accountMapper = sqlSession.getMapper(AccountMapper.class);
accountMapper.save(account);
sqlSession.commit();
sqlSession.close();
} catch (IOException e) {
e.printStackTrace();
}
}
@Override
public List<Account> findAll() {
try {
InputStream resourceAsStream = Resources.getResourceAsStream("sqlMapConfig.xml");
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(resourceAsStream);
SqlSession sqlSession = sqlSessionFactory.openSession();
AccountMapper accountMapper = sqlSession.getMapper(AccountMapper.class);
List<Account> accountList = mapper.findAll();
sqlSession.close();
return accountList;
} catch (IOException e) {
e.printStackTrace();
}
}
}
整合思路:
将
SqlSessionFactory
配置到Spring
容器中(将SqlSessionFactory
工厂的创建权交给Spring
)配置事务控制(将事务控制权交给
Spring
容器进行声明式事务控制)将部分配置在
sqlMapConfig.xml
配置文件中的部分信息转移到Spring
的配置文件中,修改后的Spring
配置文件和sqlMapConfig.xml
文件如下:Spring
配置文件:applicationContext.xml
xml<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd"> <!-- 组件扫描 扫描service和mapper --> <context:component-scan base-package="com.jlc"> <!--排除对controller的扫描--> <context:exclude-filter type="annotation" expression="org.springframework.stereotype.Controller"> </context:component-scan> <!--加载jdbc.properties--> <context:property-placeholder location="classpath:jdbc.properties"/> <!--配置数据源--> <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"> <property name="driverClass" value="${jdbc.driver}"/> <property name="jdbcUrl" value="${jdbc.url}"/> <property name="user" value="${jdbc.username}"/> <property name="password" value="${jdbc.password}"/> </bean> <!--配置MyBatis的SqlSessionFactory--> <!--mybatis-spring包中提供了工厂实现类--> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <!--加载数据源信息和MyBatis配置信息--> <property name="dataSource" ref="dataSource"/> <property name="configLocation" value="classpath:sqlMapConfig.xml"/> </bean> <!--扫描mapper所在的包,为mapper创建实现类,等价于Mybatis配置中的加载映射--> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <property name="basePackage" value="com.jlc.mapper"></property> </bean> <!--声明式事务控制--> <!--配置平台事务管理器,适用于jdbc模板--> <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> <property name="dataSource" ref="dataSource"/> </bean> <!--配置事务的增强--> <tx:advice id="txAdvice" transaction-manager="transactionManager"> <!--设置事务的属性信息--> <tx:attributes> <tx:method name="*" /> </tx:attributes> </tx:advice> <!--配置事务控制的织入--> <aop:config> <aop:advisor advice-ref="txAdvice" pointcut="execution(* com.jlc.service.impl.*.*(..))"></aop:advisor> <!--任意方法都进行事务控制--> </aop:config> </beans>
MyBatis
核心文件:sqlMapConfig.xml
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> <!--定义别名--> <typeAliases> <!--方式一,一个一个的配置别名--> <typeAlias type="com.jlc.domain.Account" alias="account"></typeAlias> <!--方式二,通过扫包的方式进行别名的配置,包下所有的实体都使用实体类作为别名--> <package name="com.jlc.domain"></package> </typeAliases> </configuration>
修改业务层的逻辑代码:
java
package com.jlc.service.impl;
import com.jlc.domain.Account;
import com.jlc.service.AccountService;
import java.util.List;
@Service("accountService")
public class AccountServiceImpl implements AccountService {
@Autowired
private AccountMapper accountMapper;
@Override
public void save(Account account) {
accountMapper.save(account);
}
@Override
public List<Account> findAll() {
return accountMapper.findAll();
}
}