2 Replies Latest reply on Dec 21, 2007 6:08 PM by bornmw

    Can I create class using reflection?

    bornmw

      Hi!
      I assume my question is about design of JBossAOP since users couldn't help me.
      My question is simple.
      I have a class that is post processed by aopc.
      Does JBossAOP design let me I instantiate it using reflection?

      When I try doing it I get this:

      java -cp .:/projects/lib/jboss-aop_1.5.5.GA/lib-50/jboss-aop-jdk50.jar:/usr/local/pluto-1.1.4/shared
      /lib/portlet-api-1.0.jar:/usr/local/pluto-1.1.4/webapps/AOPPortlet/WEB-INF/lib/concurrent.jar:/usr/l
      ocal/pluto-1.1.4/webapps/AOPPortlet/WEB-INF/lib/javassist-snapshot.jar:/usr/local/pluto-1.1.4/webapp
      s/AOPPortlet/WEB-INF/lib/jboss-common.jar:/usr/local/pluto-1.1.4/webapps/AOPPortlet/WEB-INF/lib/trov
      e.jar ConstrTest
      constructor = public Test()
      Exception in thread "main" java.lang.VerifyError: (class: org/jboss/aop/advice/ViewAspect0, method: invoke signature: (Lorg/jb
      oss/aop/joinpoint/Invocation;)Ljava/lang/Object;) Unable to pop operand off an empty stack
       at java.lang.Class.getDeclaredConstructors0(Native Method)
       at java.lang.Class.privateGetDeclaredConstructors(Class.java:2389)
       at java.lang.Class.getConstructor0(Class.java:2699)
       at java.lang.Class.newInstance0(Class.java:326)
       at java.lang.Class.newInstance(Class.java:308)
       at org.jboss.aop.advice.PerVmAdvice.generateInterceptor(PerVmAdvice.java:132)
       at org.jboss.aop.advice.PerVmAdvice.generateOptimized(PerVmAdvice.java:56)
       at org.jboss.aop.advice.AdviceFactory.create(AdviceFactory.java:68)
       at org.jboss.aop.Advisor.createInterceptorChain(Advisor.java:618)
       at org.jboss.aop.Advisor.pointcutResolved(Advisor.java:888)
       at org.jboss.aop.Advisor.resolveMethodPointcut(Advisor.java:650)
       at org.jboss.aop.ClassAdvisor.createInterceptorChains(ClassAdvisor.java:607)
       at org.jboss.aop.ClassAdvisor.access$300(ClassAdvisor.java:82)
       at org.jboss.aop.ClassAdvisor$1.run(ClassAdvisor.java:299)
       at java.security.AccessController.doPrivileged(Native Method)
       at org.jboss.aop.ClassAdvisor.attachClass(ClassAdvisor.java:271)
       at org.jboss.aop.AspectManager.initialiseClassAdvisor(AspectManager.java:591)
       at org.jboss.aop.AspectManager.getAdvisor(AspectManager.java:579)
       at Test.<clinit>(Test.java)
       at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
       at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:
      39)
       at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorIm
      pl.java:27)
       at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
       at java.lang.Class.newInstance0(Class.java:355)
       at java.lang.Class.newInstance(Class.java:308)
       at ConstrTest.main(ConstrTest.java:16)
      





      My code is:
      ClassLoader loader = Thread.currentThread().getContextClassLoader();
      Class clazz = loader.loadClass("Test");
      for (int j = 0; j < clazz.getConstructors().length; j++) {
       Constructor constructor = clazz.getConstructors()[j];
       System.out.println("constructor = " + constructor);
      }
      Test t = (Test) clazz.newInstance();
      System.out.println("t = " + t);
      



      Test is a simple class with default constructor and one method that has aspect attached to it.
      What am I doing wrong? Or is it not possible to construct aspectized classes using reflection at all?

      Many thanks.

        • 1. Re: Can I create class using reflection?
          flavia.rainone

          Hi. This question is not a discussion about design of AOP, so it belongs to the user forum.

          You have posted your question there yesterday, give us developers some time to answer to you there.

          • 2. Re: Can I create class using reflection?
            bornmw

            Flavia,

            Thanks for your reply.
            I just started to wonder if I was trying to do something that was against JBossAOP design.
            I will wait in users forum.
            Just to give you a clue - I'm trying to add aspects to Pluto portlets, and Pluto instantiates portlets using reflection, so this is also a question about JBossAOP and Pluto compatibility.