Tapestry 5
  1. Tapestry 5
  2. TAP5-1601

Sometime a method that references a field with a conduit will not be instrumented, resulting in an NPE accessing the field itself

    Details

      Description

      From ProQuest, they have a component that has this code:

      public class Layout {

      @Inject
      private ComponentResources resources;

      @Cached
      public Component getPage()

      { return resources.getContainer(); }

      }

      The generated bytecode for the advised method looks ok:

      public getPage()Lorg/apache/tapestry5/runtime/Component;
      @Lorg/apache/tapestry5/annotations/Cached;()
      NEW com/proquest/apps/onesearch/components/PageLayoutBasic$Invocation_getPage_123876a5ccf1f215
      DUP
      ALOAD 0
      ALOAD 0
      GETFIELD com/proquest/apps/onesearch/components/PageLayoutBasic.instanceContext : Lorg/apache/tapestry5/plastic/InstanceContext;
      ALOAD 0
      GETFIELD com/proquest/apps/onesearch/components/PageLayoutBasic.methodinvocationbundle_getPage_123876a5ccf1f22d : Lorg/apache/tapestry5/internal/plastic/MethodInvocationBundle;
      INVOKESPECIAL com/proquest/apps/onesearch/components/PageLayoutBasic$Invocation_getPage_123876a5ccf1f215.<init> (Ljava/lang/Object;Lorg/apache/tapestry5/plastic/InstanceContext;Lorg/apache/tapestry5/internal/plastic/MethodInvocationBundle;)V
      L0
      DUP
      ASTORE 1
      INVOKEVIRTUAL org/apache/tapestry5/internal/plastic/AbstractMethodInvocation.proceed ()Lorg/apache/tapestry5/plastic/MethodInvocation;
      ALOAD 1
      GETFIELD com/proquest/apps/onesearch/components/PageLayoutBasic$Invocation_getPage_123876a5ccf1f215.returnValue : Lorg/apache/tapestry5/runtime/Component;
      ARETURN
      L1
      LOCALVARIABLE var0 Lcom/proquest/apps/onesearch/components/PageLayoutBasic$Invocation_getPage_123876a5ccf1f215; L0 L1 1
      MAXSTACK = 1
      MAXLOCALS = 1

      ... but the bytecode for the advised method is not instrumented:

      public advised$getPage_123876a5ccf1f216()Lorg/apache/tapestry5/runtime/Component;
      @Lorg/apache/tapestry5/annotations/Cached;()
      ALOAD 0
      GETFIELD com/proquest/apps/onesearch/components/PageLayoutBasic.resources : Lorg/apache/tapestry5/ComponentResources;
      INVOKEINTERFACE org/apache/tapestry5/ComponentResources.getContainer ()Lorg/apache/tapestry5/runtime/Component;
      ARETURN
      MAXSTACK = 1
      MAXLOCALS = 1

      ... even though the necessary field conduit support method is present:

      // access flags 0x1010
      final getfieldvalue_resources()Lorg/apache/tapestry5/ComponentResources;
      ALOAD 0
      GETFIELD com/proquest/apps/onesearch/components/PageLayoutBasic.resources_FieldConduit : Lorg/apache/tapestry5/plastic/FieldConduit;
      ALOAD 0
      ALOAD 0
      GETFIELD com/proquest/apps/onesearch/components/PageLayoutBasic.instanceContext : Lorg/apache/tapestry5/plastic/InstanceContext;
      INVOKEINTERFACE org/apache/tapestry5/plastic/FieldConduit.get (Ljava/lang/Object;Lorg/apache/tapestry5/plastic/InstanceContext;)Ljava/lang/Object;
      CHECKCAST org/apache/tapestry5/ComponentResources
      DUP
      ALOAD 0
      SWAP
      PUTFIELD com/proquest/apps/onesearch/components/PageLayoutBasic.resources : Lorg/apache/tapestry5/ComponentResources;
      ARETURN
      MAXSTACK = 0
      MAXLOCALS = 0

      ... also, looking at the real class, from the client, as transformed, many other methods containing references to the field are being transformed.

        Issue Links

          Activity

            People

            • Assignee:
              Howard M. Lewis Ship
              Reporter:
              Howard M. Lewis Ship
            • Votes:
              2 Vote for this issue
              Watchers:
              2 Start watching this issue

              Dates

              • Created:
                Updated:
                Resolved:

                Development