java - spring boot中Aop的问题

Question

我的应用类

import com.example.haha.Haha;
import com.example.hehe.Hehe;
import com.example.logging.Logging;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.EnableAspectJAutoProxy;

@SpringBootApplication
@EnableAspectJAutoProxy
public class DemoApplication {

    public static void main(String[] args) throws InterruptedException {
        ApplicationContext ctx = SpringApplication.run(DemoApplication.class, args);
        for(String name:ctx.getBeanDefinitionNames()){
            System.out.println(name);
        }
        Haha haha = (Haha)ctx.getBean("hh");
        haha.haha1();
        haha.haha2();
        return;
    }

}

哈哈.java

package com.example.haha;

import org.springframework.stereotype.Component;

/**
 * Created by vamsi on 4/21/16.
 */
@Component("hh")
public class Haha {

    public Haha(){
    }


    public void haha1() throws InterruptedException {
        System.out.println("In method haha1");
        Thread.sleep(1000);
    }

    public void haha2() throws InterruptedException {
        System.out.println("In method haha2");
        Thread.sleep(2000);
    }

}

我的方面类

package com.example.logging;

import org.apache.commons.logging.Log;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.springframework.context.annotation.Bean;
import org.springframework.stereotype.Component;

/**
 * Created by vamsi on 4/21/16.
 */
@Aspect
@Component
public class Logging {
    public Logging() {
    }

    @Pointcut("execution(public * *(..))")
    private void allPublicMethods(){}

    @Around("allPublicMethods()")
    public Object profile(ProceedingJoinPoint pjp) throws Throwable {
        long start = System.currentTimeMillis();
        System.out.println(pjp.getSignature() +"begins");
        Object output = pjp.proceed();
        System.out.println(pjp.getSignature()+"completed.");
        long elapsedTime = System.currentTimeMillis() - start;
        System.out.println("Method execution time: " + elapsedTime + " milliseconds.");
        return output;
    }
}

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.example</groupId>
    <artifactId>demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>demo</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.3.3.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <java.version>1.7</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-aop</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>


</project>

这些是我的 spring boot 应用程序中的文件。我想使用 AOP 记录我的应用程序中的所有公共(public)方法。但是，当我运行我的应用程序时，出现以下错误。

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.boot.autoconfigure.AutoConfigurationPackages': Initialization of bean failed; nested exception is org.springframework.aop.framework.AopConfigException: Could not generate CGLIB subclass of class [class org.springframework.boot.autoconfigure.AutoConfigurationPackages$BasePackages]: Common causes of this problem include using a final class or a non-visible class; nested exception is java.lang.IllegalArgumentException: Cannot subclass final class org.springframework.boot.autoconfigure.AutoConfigurationPackages$BasePackages
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:553) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:772) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:839) ~[spring-context-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:538) ~[spring-context-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:766) [spring-boot-1.3.3.RELEASE.jar:1.3.3.RELEASE]
    at org.springframework.boot.SpringApplication.createAndRefreshContext(SpringApplication.java:361) [spring-boot-1.3.3.RELEASE.jar:1.3.3.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:307) [spring-boot-1.3.3.RELEASE.jar:1.3.3.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1191) [spring-boot-1.3.3.RELEASE.jar:1.3.3.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1180) [spring-boot-1.3.3.RELEASE.jar:1.3.3.RELEASE]
    at com.example.DemoApplication.main(DemoApplication.java:18) [classes/:na]
Caused by: org.springframework.aop.framework.AopConfigException: Could not generate CGLIB subclass of class [class org.springframework.boot.autoconfigure.AutoConfigurationPackages$BasePackages]: Common causes of this problem include using a final class or a non-visible class; nested exception is java.lang.IllegalArgumentException: Cannot subclass final class org.springframework.boot.autoconfigure.AutoConfigurationPackages$BasePackages
    at org.springframework.aop.framework.CglibAopProxy.getProxy(CglibAopProxy.java:213) ~[spring-aop-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.aop.framework.ProxyFactory.getProxy(ProxyFactory.java:109) ~[spring-aop-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.aop.framework.autoproxy.AbstractAutoProxyCreator.createProxy(AbstractAutoProxyCreator.java:468) ~[spring-aop-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.aop.framework.autoproxy.AbstractAutoProxyCreator.wrapIfNecessary(AbstractAutoProxyCreator.java:349) ~[spring-aop-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.aop.framework.autoproxy.AbstractAutoProxyCreator.postProcessAfterInitialization(AbstractAutoProxyCreator.java:298) ~[spring-aop-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyBeanPostProcessorsAfterInitialization(AbstractAutowireCapableBeanFactory.java:422) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1583) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:545) ~[spring-beans-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    ... 14 common frames omitted
Caused by: java.lang.IllegalArgumentException: Cannot subclass final class org.springframework.boot.autoconfigure.AutoConfigurationPackages$BasePackages
    at org.springframework.cglib.proxy.Enhancer.generateClass(Enhancer.java:457) ~[spring-core-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.cglib.transform.TransformingClassGenerator.generateClass(TransformingClassGenerator.java:33) ~[spring-core-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.cglib.core.DefaultGeneratorStrategy.generate(DefaultGeneratorStrategy.java:25) ~[spring-core-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.aop.framework.CglibAopProxy$ClassLoaderAwareUndeclaredThrowableStrategy.generate(CglibAopProxy.java:990) ~[spring-aop-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.cglib.core.AbstractClassGenerator.create(AbstractClassGenerator.java:231) ~[spring-core-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.cglib.proxy.Enhancer.createHelper(Enhancer.java:378) ~[spring-core-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.cglib.proxy.Enhancer.createClass(Enhancer.java:318) ~[spring-core-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.aop.framework.ObjenesisCglibAopProxy.createProxyClassAndInstance(ObjenesisCglibAopProxy.java:55) ~[spring-aop-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    at org.springframework.aop.framework.CglibAopProxy.getProxy(CglibAopProxy.java:203) ~[spring-aop-4.2.5.RELEASE.jar:4.2.5.RELEASE]
    ... 21 common frames omitted

Answer 1

您的切入点非常通用:

@Pointcut("execution(public * *(..))")

这将建议类路径上每个类的所有可用公共(public)方法，每一个!不幸的是，Spring AOP 无法为类路径上的某些现有类创建所需的代理(因为它们没有实现任何接口(interface)并且是 final)，因此出现错误:

Cannot subclass final class org.springframework.boot.autoconfigure.AutoConfigurationPackages$BasePackages

如果你限制你的切入点只是建议你的类，你会没事的!