Spring基于@AspectJ AOP例子
1.使用前准备
Spring在修理@Aspect注解表达式时,需要将Spring的asm模块加到类路径中。asm是轻量级的字节码处理框架,因为java的反射机制无法获取入参名,Spring就利用asm处理@AspectJ中所描述的方法入参名。
此外还需要加入aspectj.weaver和aspectj.tools类包。
2.配置使用@AspectJ切面
自动代理的配置
<aop:aspectj-autoproxy proxy-target-class="true"/> 或<aop:aspectj-autoproxy/>
<?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" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd"> <aop:aspectj-autoproxy proxy-target-class="true"/> </beans>
3.通过注解对类的进行设置
@Before
@After
@AfterReturning
@Around
@AfterThrowing
package com.baobaotao.aspectj.advanced; import org.aspectj.lang.annotation.AfterThrowing; import org.aspectj.lang.annotation.Aspect; @Aspect public class TestAspect { //-------------复合运算---------- // @Before("!target(com.baobaotao.NaiveWaiter) "+ // "&& execution(* serveTo(..)))") // public void notServeInNaiveWaiter() { // System.out.println("--notServeInNaiveWaiter() executed!--"); // } // @After("within(com.baobaotao.*) " // + " && execution(* greetTo(..)))") // public void greeToFun() { // System.out.println("--greeToFun() executed!--"); // } // // @AfterReturning("target(com.baobaotao.Waiter) || "+ // " target(com.baobaotao.Seller)") // public void waiterOrSeller(){ // System.out.println("--waiterOrSeller() executed!--"); // } // //------------引用命名切点----------// // @Before("TestNamePointcut.inPkgGreetTo()") // public void pkgGreetTo(){ // System.out.println("--pkgGreetTo() executed!--"); // } // // @Before("!target(com.baobaotao.NaiveWaiter) && " // +"TestNamePointcut.inPkgGreetTo()") // public void pkgGreetToNotNaiveWaiter(){ // System.out.println("--pkgGreetToNotNaiveWaiter() executed!--"); // } // //------------访问连接点对象----------// // @Around("execution(* greetTo(..)) && target(com.baobaotao.NaiveWaiter)") // public void joinPointAccess(ProceedingJoinPoint pjp) throws Throwable{ // System.out.println("------joinPointAccess-------"); // System.out.println("args[0]:"+pjp.getArgs()[0]); // System.out.println("signature:"+pjp.getTarget().getClass()); // pjp.proceed(); // System.out.println("-------joinPointAccess-------"); // } //------------绑定连接点参数----------// // @Before("target(com.baobaotao.NaiveWaiter) && args(name,num,..)") // public void bindJoinPointParams(int num,String name){ // System.out.println("----bindJoinPointParams()----"); // System.out.println("name:"+name); // System.out.println("num:"+num); // System.out.println("----bindJoinPointParams()----"); // } //------------绑定代理对象----------// // @Before("execution(* greetTo(..)) && this(waiter)") // @Before("this(waiter)") // public void bindProxyObj(Waiter waiter){ // System.out.println("----bindProxyObj()----"); // System.out.println(waiter.getClass().getName()); // System.out.println("----bindProxyObj()----"); // } //------------绑定类标注对象----------// // @Before("@within(m)") // public void bindTypeAnnoObject(Monitorable m){ // System.out.println("----bindTypeAnnoObject()----"); // System.out.println(m.getClass().getName()); // System.out.println("----bindTypeAnnoObject()----"); // } //------------绑定抛出的异常----------// // @AfterReturning(value="target(com.baobaotao.SmartSeller)",returning="retVal") // public void bingReturnValue(int retVal){ // System.out.println("----bingReturnValue()----"); // System.out.println("returnValue:"+retVal); // System.out.println("----bingReturnValue()----"); // } // //------------绑定抛出的异常----------// @AfterThrowing(value="target(com.baobaotao.SmartSeller)",throwing="iae") public void bindException(IllegalArgumentException iae){ System.out.println("----bindException()----"); System.out.println("exception:"+iae.getMessage()); System.out.println("----bindException()----"); } }
其中相关的类
public interface Waiter { @NeedTest public void greetTo(String clientName); public void serveTo(String clientName); } @Retention(RetentionPolicy.RUNTIME) @Target(ElementType.TYPE) public @interface Monitorable { } @Monitorable public class NaiveWaiter implements Waiter { @NeedTest public void greetTo(String clientName) { System.out.println("NaiveWaiter:greet to "+clientName+"..."); } @NeedTest public void serveTo(String clientName){ System.out.println("NaiveWaiter:serving "+clientName+"..."); } public void smile(String clientName,int times){ System.out.println("NaiveWaiter:smile to "+clientName+ times+"times..."); } } public class NaughtyWaiter implements Waiter { public void greetTo(String clientName) { System.out.println("NaughtyWaiter:greet to "+clientName+"..."); } public void serveTo(String clientName){ System.out.println("NaughtyWaiter:serving "+clientName+"..."); } public void joke(String clientName,int times){ System.out.println("NaughtyWaiter:play "+times+" jokes to "+clientName+"..."); } } public interface Seller { int sell(String goods,String clientName); } public class SmartSeller implements Seller { public int sell(String goods,String clientName) { System.out.println("SmartSeller: sell "+goods +" to "+clientName+"..."); return 100; } public void checkBill(int billId){ if(billId == 1) throw new IllegalArgumentException("iae Exception"); else throw new RuntimeException("re Exception"); } } public class TestNamePointcut { @Pointcut("within(com.baobaotao.*)") private void inPackage(){} @Pointcut("execution(* greetTo(..)))") protected void greetTo(){} @Pointcut("inPackage() and greetTo()") public void inPkgGreetTo(){} }
3.测试例子
package com.baobaotao.aspectj.advanced; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; import com.baobaotao.SmartSeller; import com.baobaotao.Waiter; public class AdvancedTest { public static void main(String[] args) { String configPath = "com/baobaotao/aspectj/advanced/beans.xml"; ApplicationContext ctx = new ClassPathXmlApplicationContext(configPath); Waiter naiveWaiter = (Waiter) ctx.getBean("naiveWaiter"); //NaiveWaiter naiveWaiter1 = (NaiveWaiter) ctx.getBean("naiveWaiter"); Waiter naughtyWaiter = (Waiter) ctx.getBean("naughtyWaiter"); // naiveWaiter.greetTo("John"); // naiveWaiter.serveTo("John"); // naughtyWaiter.greetTo("Tom"); // naughtyWaiter.serveTo("Tom"); //--通过joinPoint接口访问连接点上下文信息 // naiveWaiter.greetTo("John"); //--绑定连接点参数 //((NaiveWaiter)naiveWaiter).smile("John",2); //naiveWaiter1.smile("John",2); //--绑定代理对象 // naiveWaiter.greetTo("John"); //--绑定类注解 // ((NaiveWaiter)naiveWaiter).greetTo("John"); //绑定返回值 // SmartSeller seller = (SmartSeller) ctx.getBean("seller"); // seller.sell("Beer","John"); //绑定异常 SmartSeller seller = (SmartSeller) ctx.getBean("seller"); seller.checkBill(2); //seller.checkBill(1); } }