InvocationContextImp cleans target field if occurs an exception

[thiago soares]

Hi all,

I'm doing some tests using ApacheOpenWebBeans 1.1.7 as the CDI implementation.
I am using a Framework (frameworkdemoiselle.gov.br) that offers an
interceptor that handles exceptions thrown by the target bean.

A summary of this interceptor is written bellow:

=========================
@AroundInvoke
public Object manage(final InvocationContext ic) throws Exception {
        Object result = null;

        try {
                result = ic.proceed();

        } catch (Exception cause) {
                // Handle Exception here
                target = ic.getTarget();
                ...

        }
        return result;
}
=========================

The "Handle Exception" logic uses the target bean. The problem is that
the "ic.getTarget()" method returns null and i get a
NullPointerException.
I've done the same test using WELD and ic.getTarget() does not returns null.

Analyzing the source code of the class
"org.apache.webbeans.intercept.InvocationContextImpl" I see that it
destroys the target instance when it catches an exception.

=========================
public Object proceed() throws Exception
{
        try
        {
            if (type.equals(InterceptionType.AROUND_INVOKE))
            {
                return proceedAroundInvokes(interceptorDatas);
            }
            else if (type.equals(InterceptionType.AROUND_TIMEOUT))
            {
                return proceedAroundTimeouts(interceptorDatas);
            }
            return proceedCommonAnnots(interceptorDatas, type);

        }
        catch (InvocationTargetException ite)
        {
            target = null; // destroy target instance    <<=================

            // Try to provide the original exception to the interceptor stack,
            // not the InvocationTargetException from Method.invoke
            Throwable t = ite.getCause();
            if (t instanceof Exception)
            {
                throw (Exception) t;
            }
            throw ite;
        }
        catch (Exception e)
        {
            target = null; // destroy target instance <<=================

            throw e;
        }
}
=========================

My question is: Why we need to destroy the target instance when occurs
an Exception? Doing it so, the interceptor cannot get the target after
invoking proceed() method.

Thanks,

Thiago