CGLIB Proxy, no default constructor

[Toxic]

Hi,

I'm trying to proxy a concrete class (com.company.Concrete) which only as a one-argument constructor.

ApplicationContext

        <aop:aspectj-autoproxy proxy-target-class="true" />
	<bean id="concrete" class="com.company.Concrete" scope="prototype" />

Initialization code (try 1):

        Object args = ... 
        // throws exception
        Concrete c = (Concrete) applicationContext.getBean("concrete", args);

Initialization code (try 2):

       Object args = ... 
       // Also throws exception
       Concrete concrete = (Concrete) applicationContext.getAutowireCapableBeanFactory().initializeBean(
             new Concrete(args), "concrete");

Exception

rg.springframework.aop.framework.AopConfigException: Could not generate CGLIB subclass of class [class com.company.Concrete]: Common causes of this problem include using a final class or a non-visible class; nested exception is java.lang.IllegalArgumentException: Superclass has no null constructors but no arguments were given
	at org.springframework.aop.framework.Cglib2AopProxy.getProxy(Cglib2AopProxy.java:212)
	at org.springframework.aop.framework.ProxyFactory.getProxy(ProxyFactory.java:112)
	at org.springframework.aop.framework.autoproxy.AbstractAutoProxyCreator.createProxy(AbstractAutoProxyCreator.java:476)
	at org.springframework.aop.framework.autoproxy.AbstractAutoProxyCreator.wrapIfNecessary(AbstractAutoProxyCreator.java:362)
	at org.springframework.aop.framework.autoproxy.AbstractAutoProxyCreator.postProcessAfterInitialization(AbstractAutoProxyCreator.java:322)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyBeanPostProcessorsAfterInitialization(AbstractAutowireCapableBeanFactory.java:407)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1418)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:519)
	... 10 more
Caused by: java.lang.IllegalArgumentException: Superclass has no null constructors but no arguments were given
	at net.sf.cglib.proxy.Enhancer.emitConstructors(Enhancer.java:721)
	at net.sf.cglib.proxy.Enhancer.generateClass(Enhancer.java:499)
	at net.sf.cglib.transform.TransformingClassGenerator.generateClass(TransformingClassGenerator.java:33)
	at net.sf.cglib.core.DefaultGeneratorStrategy.generate(DefaultGeneratorStrategy.java:25)
	at net.sf.cglib.core.AbstractClassGenerator.create(AbstractClassGenerator.java:216)
	at net.sf.cglib.proxy.Enhancer.createHelper(Enhancer.java:377)
	at net.sf.cglib.proxy.Enhancer.create(Enhancer.java:285)
	at org.springframework.aop.framework.Cglib2AopProxy.getProxy(Cglib2AopProxy.java:200)
	... 17 more

I don't see why this should be a problem.
I'm using GenericApplicationContext which invokes getBean() with the necessary constructor arguments. Shouldn't spring delegate to the appropriate CGLIB method (which does take constructor arguments) ?


Note, I've also tried using a private default constructor with no success.



Regards,
Johan