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My Application class

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;
    }

}

Haha.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);
    }

}

My Aspect Class

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>

These are the files in my spring boot application. I want to log around all the public methods in my application using AOP. Bu when I run my application it gives the following error.

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
Manu
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2 Answers2

19

Your Pointcut is so generic:

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

That will advice all available public methods of every class on the classpath, every single of them! Unfortunately, Spring AOP can't make the required proxy for some present classes on the classpath (Since they're not implementing any interface and are final), hence the error:

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

If you restrict your pointcut to just advice your classes, you would be fine!

Ali Dehghani
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  • It worked. I will just rephrase my understanding, correct me if I'm wrong. Whenever we advice some method in a class, spring container creates a proxy class by extending the target class and implements the advice and the method using proxy class. Since I am advising all the public methods, it creates proxy class for final classes too. – Manu Apr 21 '16 at 16:54
  • Spring will use different mechanisms for creating that proxy. One of them is to create a subclass from the target class. I guess implementing the interface and AspectJ proxies are also options. – Ali Dehghani Apr 21 '16 at 16:57
  • http://docs.spring.io/spring/docs/current/spring-framework-reference/htmlsingle/#aop-introduction-proxies – Ali Dehghani Apr 21 '16 at 17:03
  • Suclassing ( By using CGLIB) is used by default if a business object does not implement an interface. Using `proxyTargetClass` attribute of the `EnableAspectJAutoProxy` you can determine the default approach for proxy-ing – Ali Dehghani Apr 21 '16 at 17:06
  • Thanks for answering my queries. what does @EnableAspectJAutoProxy this annotation do? – Manu Apr 21 '16 at 17:10
  • This is a recurring theme in Spring Framework to declaratively enable some feature. `EnableAspectJAutoProxy` will enable Spring support for configuring Spring AOP based on `@AspectJ` aspects, and autoproxying beans based on whether or not they are advised by those aspects – Ali Dehghani Apr 21 '16 at 17:14
  • Spring has a great documentation, for more information read the doc – Ali Dehghani Apr 21 '16 at 17:15
10

Your allPublicMethods pointcut is too broad. It's being applied to every public method of every class. One class that matches is org.springframework.boot.autoconfigure.AutoConfigurationPackages$BasePackages. It's declared as final which prevents the advice from being applied to it.

You should narrow the scope of your pointcut, for example by only applying it to code in your own com.example package:

@Pointcut("execution(public * com.example..*(..))")
Andy Wilkinson
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