首先AOP就是一个动态代理,主要运用在事务控制,日志记录,安全控制等方面
1.连接点(Joinpoint):一个连接点 总是 代表一个方法的执行.
2.切入点(Pointcut):匹配连接点的 表达式
3.通知(Advice):连接点执行的动作 包括 执行前 执行后 环绕
通知的类型分为五种: 前置通知 返回后通知 抛出异常后通知 后通知 环绕通知
4.切面(Aspect): 连接点+切入点+通知=切面
5.目标对象(Target Object):就是委托类对象
6.织入(Weaving):动态代理的过程
使用xml配置AOP 实现添加日志操作
XML配置:
applicationContext-action.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:p="http://www.springframework.org/schema/p"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.2.xsd" >
<bean id="userAction" class="com.cdsxt.action.UserAction" scope="prototype" >
<property name="userService" ref="userService" />
</bean>
</beans>
applicationContext-service.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:p="http://www.springframework.org/schema/p"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.2.xsd" >
<bean id="userService" class="com.cdsxt.service.impl.UserServiceImpl">
<property name="userDao" ref="userDao" />
</bean>
</beans>
applicationContext-dao.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:p="http://www.springframework.org/schema/p"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.2.xsd" >
<bean id="userDao" class="com.cdsxt.dao.impl.UserDaoImpl" parent="baseDao" ></bean>
</beans>
applicationContext-resource.xml:一般把base资源性配置和公共性配置(比如连接数据库)配置在这里面,AOP的配置也在这里面
<?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-3.2.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-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/context
http://www.springframework.org/schema/context/spring-context-3.2.xsd" >
<bean id="baseDao" class="com.base.impl.BaseDaoImpl" lazy-init="true" ></bean>
<!-- 用aop完成以下逻辑：
执行service 层 所有类 的 add 方法 后 添加日志操作
步骤如下：
1：写一个类 并 在applicationContext-resource.xml内配置
2: 写aop:config
配置切入点
配置切面 ref="自定义的通知类"
配置通知类型
-->
<bean id="logAdvice" class="com.cdsxt.advice.LogAdvice" />
<aop:config >
<aop:pointcut expression="execution(public * com.cdsxt.service.impl.*.add*(..))" id="logCut"/>
<aop:aspect ref="logAdvice">
<!-- <aop:after method="addLog" pointcut-ref="logCut" />
<aop:before method="addBefore" pointcut-ref="logCut"/>
<aop:around method="addAround" pointcut-ref="logCut"/> -->
<aop:after-returning method="addReturn" pointcut-ref="logCut"/>
</aop:aspect>
</aop:config>
</beans>
base:
public interface BaseDao<T> {}
public class BaseDaoImpl<T> implements BaseDao<T> {
private Class clazz;
public BaseDaoImpl() {
ParameterizedType type = (ParameterizedType) this.getClass().getGenericSuperclass();
clazz=(Class) type.getActualTypeArguments()[0];
}
public Class getClazz() {
return clazz;
}
public void setClazz(Class clazz) {
this.clazz = clazz;
}
}
action:
public class UserAction {
private UserService userService;
public void add(){
System.out.println("======UserAction=======");
userService.add();
}
public UserService getUserService() {
return userService;
}
public void setUserService(UserService userService) {
this.userService = userService;
}
public static void main(String[] args) {
String[] rs = new String[]{"applicationContext-action.xml",
"applicationContext-dao.xml","applicationContext-resource.xml","applicationContext-service.xml"};
ApplicationContext context = new ClassPathXmlApplicationContext(rs);
UserAction u1= (UserAction) context.getBean("userAction");
u1.add();
}
}
service:
public interface UserService {
public void add();
}
public class UserServiceImpl implements UserService{
private UserDao userDao;
@Override
public void add() {
System.out.println("===========UserServiceImpl==========");
userDao.add();
}
public UserDao getUserDao() {
return userDao;
}
public void setUserDao(UserDao userDao) {
this.userDao = userDao;
}
}
dao:
public interface UserDao extends BaseDao<User>{
public void add();
}
public class UserDaoImpl extends BaseDaoImpl<User> implements UserDao{
@Override
public void add() {
System.out.println("======UserDaoImpl========");
}
}
po:
public class User {}
advice:
public class LogAdvice {
public void addReturn(){
System.out.println("正常返回后通知!!!");
}
public void addLog(){
System.out.println("完成了日志操作!!!");
}
public void addBefore(JoinPoint jp){
System.out.println("权限判断!!!!");
System.out.println(jp.getTarget().getClass());
}
public void addAround(ProceedingJoinPoint pjp) {
try {
System.out.println("环绕执行前");
pjp.proceed();
System.out.println("环绕执行后");
} catch (Throwable e) {
e.printStackTrace();
}
}
}