声明式事务

配置文件中我们需要加一个tx命名空间，同时配置数据库链接、事务通知和AOP。
AOP的作用就是将事务通知加入到匹配的类与方法中，当调用匹配的类和方法的时候就会触发事务

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

		<context:component-scan base-package="jee.pk2"></context:component-scan>
    	<!-- 引入jdbc.properties -->
    	<context:property-placeholder location="jdbc.properties"/>
    	<!-- 配置dbcp数据库 -->
    	<bean id="dataSource"
			class="org.apache.commons.dbcp2.BasicDataSource"
			destroy-method="close">
			<property name="driverClassName" value="${driverClassName}" />
			<property name="url" value="${url}" />
			<property name="username" value="${uName}" />
			<property name="password" value="${password}" />
			<property name="initialSize" value="3" />
		</bean>
		
		<!-- 事务管理器 -->
		<bean id="txManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
			<property name="dataSource" ref="dataSource"></property>
		</bean>
		
		<!-- 配置一个事物通知 -->
		<tx:advice id="txAdvice" transaction-manager="txManager">
			<tx:attributes>
			<!-- 以get开头的所有方法都使用只读事务，只读事务可以提高查询效率 -->
			<tx:method name="get*" read-only="true" />
			<!-- 其他方法是普通事务 -->
			<tx:method name="*" />
		</tx:attributes>
		</tx:advice>
		
		<aop:config>
			<aop:pointcut id="userServiceOperation" expression="execution(* jee.pk2.UserService.*(..))" />
			<!-- 通知器，通知和切入点 -->
			<aop:advisor advice-ref="txAdvice"
				pointcut-ref="userServiceOperation"/>
		</aop:config>
		
</beans>

加入事务的类

package jee.pk2;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.TransactionStatus;
import org.springframework.transaction.support.TransactionCallbackWithoutResult;
import org.springframework.transaction.support.TransactionTemplate;

@Component("userService")
public class UserServiceImpl implements UserService {

	
	private UserDao userDao;
	
	@Autowired
   public void setUserDao(UserDao userDao) {
		this.userDao = userDao;
	}
	
	@Override
	public void remove() {
		
		userDao.delete(3);
		if(1==1)
		{
			throw new RuntimeException("某个错误");
		}
		userDao.delete(2);
		
		
	}

}

主方法：

package jee.pk2;

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

public class APP {

	public static void main(String[] args) {
		ApplicationContext ac=new ClassPathXmlApplicationContext("beans_pk2.xml");
		UserService userService=ac.getBean("userService", UserService.class);
		userService.remove();
	}
}