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1) Below is the small project I have where I do want logging with SpringAOP. Using spring-aop-4.1.6.RELEASE.jar and below is LoggingAspect.java with few point cuts. 

package com.myprj.aop.aspect;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.springframework.stereotype.Component;

@Aspect
@Component
public class LoggingAspect {
    private final Log log = LogFactory.getLog(getClass());

    @Before("logForAllMethods()") // after advice with name pointcut that declared as name logForAllMethods()
    public void beforeAdviceForAllMethods(JoinPoint jp) throws Throwable {
        Object clazz = jp.getTarget().getClass().getName();
        String methodName = jp.getSignature().getName();
        log.info("Before Entering to Class " + clazz + " With Method Name " + methodName);
        // getting method parameter name
        Object[] obj = jp.getArgs();
        for (Object o : obj) {
            if (o != null) {
                log.info("Parameter Name..." + o.toString());
            } else {
                log.info("");
            }
        }

    }

    @After("logForAllMethods()") // after advice with name pointcut that declared as name logForAllMethods()
    public void afterAdviceForAllMethods(JoinPoint jp) throws Throwable {
        Object clazz = jp.getTarget().getClass().getName();
        String methodName = jp.getSignature().getName();
        log.info("After Entring to Method " + methodName + " in Calss " + clazz);
    }

    @Pointcut("execution(public * *(..))")      // enable for all public methods
    public void logForAllMethods() {
    }
}

Also below is the sample Service and ServiceImpl classes I have 

package com.myprj.aop.service;

public interface TransferService {

    void transfer(String accountA, String accountB, Long amount);

    Double checkBalance(String account);

    Long withdrawal(String account, Long amount);

    void diposite(String account, Long amount);
}


package com.myprj.aop.service;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.stereotype.Service;

@Service
public class TransferServiceImpl implements TransferService {

    @Autowired
    @Qualifier("finalClass")
    FinalClass finalClass;

    @Override
    public void transfer(String accountA, String accountB, Long amount) {
        System.out.println(amount + " Amount has been tranfered from " + accountA + " to " + accountB);
    }

    @Override
    public Double checkBalance(String account) {
        System.out.println("Available balance: 50000");
        finalClass.toString();
        return new Double(50000);
    }

    @Override
    public Long withdrawal(String account, Long amount) {
        System.out.println("Withdrawal amount: " + amount);
        finalClass.toString();
        return amount;
    }

    @Override
    public void diposite(String account, Long amount) {
        System.out.println(amount + " Amount has been diposited to " + account);
        finalClass.toString();
    }

}

Also, I have a Singleton class where few methods need to be invoked like below.

package com.myprj.aop.service;

public class FinalClass {

    private String constructorParam;

    private FinalClass(String param) {
        constructorParam = param;
    }

    @Override
    public String toString() {
        System.out.println(constructorParam);
        return constructorParam;
    }
}

Below is applicationContext.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:util="http://www.springframework.org/schema/util"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:aop="http://www.springframework.org/schema/aop"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/util
        http://www.springframework.org/schema/util/spring-util.xsd
        http://www.springframework.org/schema/aop
        http://www.springframework.org/schema/aop/spring-aop-3.0.xsd">
    <context:component-scan base-package="com.myprj.aop.*" />       
    <bean id="finalClass" class="com.myprj.aop.service.FinalClass">
        <constructor-arg value="constructorArg"></constructor-arg>
    </bean>
    <aop:aspectj-autoproxy/>    
</beans>

Main class:

package com.myprj.aop.test;

import org.springframework.context.ApplicationContext;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.myprj.aop.config.AppConfig;
import com.myprj.aop.service.TransferService;


public class Main {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // ConfigurableApplicationContext applicationContext = new AnnotationConfigApplicationContext(AppConfig.class);
        ApplicationContext applicationContext = new ClassPathXmlApplicationContext("applicationContext.xml");
        TransferService transferService = applicationContext.getBean(TransferService.class);
        transferService.transfer("accountA", "accountB", 50000l);
        transferService.checkBalance("accountA");
        transferService.diposite("accountA", 50000l);
        transferService.withdrawal("accountB", 40000l);
        //applicationContext.close();
    }

}

Get below error

WARNING: Exception encountered during context initialization - cancelling refresh attempt
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'transferServiceImpl': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.myprj.aop.service.FinalClass com.myprj.aop.service.TransferServiceImpl.finalClass; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'finalClass' defined in class path resource [applicationContext.xml]: Initialization of bean failed; nested exception is org.springframework.aop.framework.AopConfigException: Could not generate CGLIB subclass of class [class com.myprj.aop.service.FinalClass]: Common causes of this problem include using a final class or a non-visible class; nested exception is java.lang.IllegalArgumentException: No visible constructors in class com.myprj.aop.service.FinalClass
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:334)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1210)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:755)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480)
    at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:139)
    at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:83)
    at com.myprj.aop.test.Main.main(Main.java:19)
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.myprj.aop.service.FinalClass com.myprj.aop.service.TransferServiceImpl.finalClass; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'finalClass' defined in class path resource [applicationContext.xml]: Initialization of bean failed; nested exception is org.springframework.aop.framework.AopConfigException: Could not generate CGLIB subclass of class [class com.myprj.aop.service.FinalClass]: Common causes of this problem include using a final class or a non-visible class; nested exception is java.lang.IllegalArgumentException: No visible constructors in class com.myprj.aop.service.FinalClass
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:561)
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:331)
    ... 13 more
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'finalClass' defined in class path resource [applicationContext.xml]: Initialization of bean failed; nested exception is org.springframework.aop.framework.AopConfigException: Could not generate CGLIB subclass of class [class com.myprj.aop.service.FinalClass]: Common causes of this problem include using a final class or a non-visible class; nested exception is java.lang.IllegalArgumentException: No visible constructors in class com.myprj.aop.service.FinalClass
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:547)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1120)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1044)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:942)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:533)
    ... 15 more
Caused by: org.springframework.aop.framework.AopConfigException: Could not generate CGLIB subclass of class [class com.myprj.aop.service.FinalClass]: Common causes of this problem include using a final class or a non-visible class; nested exception is java.lang.IllegalArgumentException: No visible constructors in class com.myprj.aop.service.FinalClass
    at org.springframework.aop.framework.CglibAopProxy.getProxy(CglibAopProxy.java:212)
    at org.springframework.aop.framework.ProxyFactory.getProxy(ProxyFactory.java:109)
    at org.springframework.aop.framework.autoproxy.AbstractAutoProxyCreator.createProxy(AbstractAutoProxyCreator.java:447)
    at org.springframework.aop.framework.autoproxy.AbstractAutoProxyCreator.wrapIfNecessary(AbstractAutoProxyCreator.java:333)
    at org.springframework.aop.framework.autoproxy.AbstractAutoProxyCreator.postProcessAfterInitialization(AbstractAutoProxyCreator.java:293)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyBeanPostProcessorsAfterInitialization(AbstractAutowireCapableBeanFactory.java:422)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1579)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:539)
    ... 24 more
Caused by: java.lang.IllegalArgumentException: No visible constructors in class com.myprj.aop.service.FinalClass
    at org.springframework.cglib.proxy.Enhancer.filterConstructors(Enhancer.java:531)
    at org.springframework.cglib.proxy.Enhancer.generateClass(Enhancer.java:448)
    at org.springframework.cglib.transform.TransformingClassGenerator.generateClass(TransformingClassGenerator.java:33)
    at org.springframework.cglib.core.DefaultGeneratorStrategy.generate(DefaultGeneratorStrategy.java:25)
    at org.springframework.cglib.core.AbstractClassGenerator.create(AbstractClassGenerator.java:216)
    at org.springframework.cglib.proxy.Enhancer.createHelper(Enhancer.java:377)
    at org.springframework.cglib.proxy.Enhancer.createClass(Enhancer.java:317)
    at org.springframework.aop.framework.ObjenesisCglibAopProxy.createProxyClassAndInstance(ObjenesisCglibAopProxy.java:57)
    at org.springframework.aop.framework.CglibAopProxy.getProxy(CglibAopProxy.java:202)
    ... 31 more

Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'transferServiceImpl': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.myprj.aop.service.FinalClass com.myprj.aop.service.TransferServiceImpl.finalClass; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'finalClass' defined in class path resource [applicationContext.xml]: Initialization of bean failed; nested exception is org.springframework.aop.framework.AopConfigException: Could not generate CGLIB subclass of class [class com.myprj.aop.service.FinalClass]: Common causes of this problem include using a final class or a non-visible class; nested exception is java.lang.IllegalArgumentException: No visible constructors in class com.myprj.aop.service.FinalClass
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:334)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1210)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:755)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480)
    at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:139)
    at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:83)
    at com.myprj.aop.test.Main.main(Main.java:19)
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: com.myprj.aop.service.FinalClass com.myprj.aop.service.TransferServiceImpl.finalClass; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'finalClass' defined in class path resource [applicationContext.xml]: Initialization of bean failed; nested exception is org.springframework.aop.framework.AopConfigException: Could not generate CGLIB subclass of class [class com.myprj.aop.service.FinalClass]: Common causes of this problem include using a final class or a non-visible class; nested exception is java.lang.IllegalArgumentException: No visible constructors in class com.myprj.aop.service.FinalClass
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:561)
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:331)
    ... 13 more
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'finalClass' defined in class path resource [applicationContext.xml]: Initialization of bean failed; nested exception is org.springframework.aop.framework.AopConfigException: Could not generate CGLIB subclass of class [class com.myprj.aop.service.FinalClass]: Common causes of this problem include using a final class or a non-visible class; nested exception is java.lang.IllegalArgumentException: No visible constructors in class com.myprj.aop.service.FinalClass
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:547)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1120)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1044)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:942)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:533)
    ... 15 more
Caused by: org.springframework.aop.framework.AopConfigException: Could not generate CGLIB subclass of class [class com.myprj.aop.service.FinalClass]: Common causes of this problem include using a final class or a non-visible class; nested exception is java.lang.IllegalArgumentException: No visible constructors in class com.myprj.aop.service.FinalClass
    at org.springframework.aop.framework.CglibAopProxy.getProxy(CglibAopProxy.java:212)
    at org.springframework.aop.framework.ProxyFactory.getProxy(ProxyFactory.java:109)
    at org.springframework.aop.framework.autoproxy.AbstractAutoProxyCreator.createProxy(AbstractAutoProxyCreator.java:447)
    at org.springframework.aop.framework.autoproxy.AbstractAutoProxyCreator.wrapIfNecessary(AbstractAutoProxyCreator.java:333)
    at org.springframework.aop.framework.autoproxy.AbstractAutoProxyCreator.postProcessAfterInitialization(AbstractAutoProxyCreator.java:293)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyBeanPostProcessorsAfterInitialization(AbstractAutowireCapableBeanFactory.java:422)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1579)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:539)
    ... 24 more
Caused by: java.lang.IllegalArgumentException: No visible constructors in class com.myprj.aop.service.FinalClass
    at org.springframework.cglib.proxy.Enhancer.filterConstructors(Enhancer.java:531)
    at org.springframework.cglib.proxy.Enhancer.generateClass(Enhancer.java:448)
    at org.springframework.cglib.transform.TransformingClassGenerator.generateClass(TransformingClassGenerator.java:33)
    at org.springframework.cglib.core.DefaultGeneratorStrategy.generate(DefaultGeneratorStrategy.java:25)
    at org.springframework.cglib.core.AbstractClassGenerator.create(AbstractClassGenerator.java:216)
    at org.springframework.cglib.proxy.Enhancer.createHelper(Enhancer.java:377)
    at org.springframework.cglib.proxy.Enhancer.createClass(Enhancer.java:317)
    at org.springframework.aop.framework.ObjenesisCglibAopProxy.createProxyClassAndInstance(ObjenesisCglibAopProxy.java:57)
    at org.springframework.aop.framework.CglibAopProxy.getProxy(CglibAopProxy.java:202)
    ... 31 more

The inject injection is failing. After googling, many have suggested setter based injection. But when singleton class is created more operations are done in actual code. Also as per below link, this has been fixed in Spring 4.0. What is wrong with my code?

halfer
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user1876040
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    I give you a hint: `IllegalArgumentException: No visible constructors in class com.myprj.aop.service.FinalClass` and `*private* FinalClass(String param) {` – zapl Oct 15 '18 at 07:50
  • Hi @zapl, Thanks, My requirement is the singleton FinalClass class will not have public constructor. So to inject it, creating the bean in the applicationContext.xml and need to use that qualified bean in all other places. If i add a public constructor then it will not meet the purpose of singleton. correct? – user1876040 Oct 15 '18 at 07:57
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    The constructor visibility is irrelevant when nobody else uses it. Spring will use it only once, thus provide a single instance throughout your application. You can also use a `protected` constructor because https://stackoverflow.com/questions/3952815/extends-of-the-class-with-private-constructor is what happens – zapl Oct 15 '18 at 08:22
  • Please read [Under what circumstances may I add “urgent” or other similar phrases to my question, in order to obtain faster answers?](//meta.stackoverflow.com/q/326569) - the summary is that this is not an ideal way to address volunteers, and is probably counterproductive to obtaining answers. Please refrain from adding this to your questions. – halfer Oct 15 '18 at 17:17
  • @zapl, I found another workaround to solve the issue, i used && !within(Singleton class) from being injected and weaved in my LoggingAspect.java. So i will do my explicit logging in that file. Thanks for the suggestions. – user1876040 Oct 17 '18 at 07:18
  • @halfer, Apologies for that. Will take an note on that. – user1876040 Oct 17 '18 at 07:20

3 Answers3

2

as your exception says itself 

No visible constructors in class com.myprj.aop.service.FinalClass

change your private constructor to public.

Michal
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1

It tells you what the problem is: No visible constructors in class com.myprj.aop.service.FinalClass.

There is no way for spring to "guess" which static getInstance() method to call to instantiate the singleton.
You must provide a public empty c'tor for it.

If you use spring accross your application, you can define FinalClass as a singleton using the @Scope property.

Yoav Gur
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I had the same issue with my service that was modularized. I solved the issue by adding the line

  requires spring.aop;

to module-info.java

stenix
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