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Shadow extraction and advice inlining in around advice weaver generate repeated methods for occurrences of an identical shadow on a same class. This is an example: public class BugExample { public static void main(String[] args) { new BugExample().run(); } private void run() { int x = foo(-5); int y = foo(1); int z = foo(2); int w = foo(0); System.out.println("x=" + x + " y=" + y + " z=" + z + " w=" + w); } private int foo(int v) { return v; } public static aspect BugAspect { pointcut fooCalls(int v): call(* BugExample.foo(int)) && args(v); int around(int v): fooCalls(v) { if (v > 0) return proceed(v); else return 0; } } } The result of "javap -c -private BugExample" is at the end of this report (it's rather big). In it you may realize that there is no difference between the several proceed methods, and the only difference between the several advice inline methods is which proceed method invoked (and since those are equivalent, there is no semantic difference between the advice methods either). I have fixed this problem by applying an aspect to the AspectJ weaver, which caches shadow and advice methods and reuses them as possible. This is done by capturing calls to BcelShadow.extractShadow and avoiding such calls if a method with the same signature has already been created. The same is done for the creation of local advice methods. Of course, this only indicates a path to a (pure Java) final solution. D:\trabalho\mestrado\pesquisa\ajc-bugreport\bin>javap -c -private BugExample Compiled from "BugExample.java" public class BugExample extends java.lang.Object{ public BugExample(); Code: 0: aload_0 1: invokespecial #9; //Method java/lang/Object."<init>":()V 4: return public static void main(java.lang.String[]); Code: 0: new #2; //class BugExample 3: dup 4: invokespecial #17; //Method "<init>":()V 7: invokespecial #20; //Method run:()V 10: return private void run(); Code: 0: aload_0 1: bipush -5 3: istore 5 5: astore 6 7: aload_0 8: aload 6 10: iload 5 12: invokestatic #84; //Method BugExample$BugAspect.aspectOf:()LBugExample$BugAspect; 15: iload 5 17: aconst_null 18: invokestatic #88; //Method foo_aroundBody1$advice:(LBugExample;LBugExample;ILBugExample$BugAspect;ILorg/aspectj/runtime/internal/AroundClosure;)I 21: istore_1 22: aload_0 23: iconst_1 24: istore 7 26: astore 8 28: aload_0 29: aload 8 31: iload 7 33: invokestatic #84; //Method BugExample$BugAspect.aspectOf:()LBugExample$BugAspect; 36: iload 7 38: aconst_null 39: invokestatic #94; //Method foo_aroundBody3$advice:(LBugExample;LBugExample;ILBugExample$BugAspect;ILorg/aspectj/runtime/internal/AroundClosure;)I 42: istore_2 43: aload_0 44: iconst_2 45: istore 9 47: astore 10 49: aload_0 50: aload 10 52: iload 9 54: invokestatic #84; //Method BugExample$BugAspect.aspectOf:()LBugExample$BugAspect; 57: iload 9 59: aconst_null 60: invokestatic #100; //Method foo_aroundBody5$advice:(LBugExample;LBugExample;ILBugExample$BugAspect;ILorg/aspectj/runtime/internal/AroundClosure;)I 63: istore_3 64: aload_0 65: iconst_0 66: istore 11 68: astore 12 70: aload_0 71: aload 12 73: iload 11 75: invokestatic #84; //Method BugExample$BugAspect.aspectOf:()LBugExample$BugAspect; 78: iload 11 80: aconst_null 81: invokestatic #106; //Method foo_aroundBody7$advice:(LBugExample;LBugExample;ILBugExample$BugAspect;ILorg/aspectj/runtime/internal/AroundClosure;)I 84: istore 4 86: getstatic #32; //Field java/lang/System.out:Ljava/io/PrintStream; 89: new #34; //class java/lang/StringBuilder 92: dup 93: ldc #36; //String x= 95: invokespecial #39; //Method java/lang/StringBuilder."<init>":(Ljava/lang/String;)V 98: iload_1 99: invokevirtual #43; //Method java/lang/StringBuilder.append:(I)Ljava/lang/StringBuilder; 102: ldc #45; //String y= 104: invokevirtual #48; //Method java/lang/StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder; 107: iload_2 108: invokevirtual #43; //Method java/lang/StringBuilder.append:(I)Ljava/lang/StringBuilder; 111: ldc #50; //String z= 113: invokevirtual #48; //Method java/lang/StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder; 116: iload_3 117: invokevirtual #43; //Method java/lang/StringBuilder.append:(I)Ljava/lang/StringBuilder; 120: ldc #52; //String w= 122: invokevirtual #48; //Method java/lang/StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder; 125: iload 4 127: invokevirtual #43; //Method java/lang/StringBuilder.append:(I)Ljava/lang/StringBuilder; 130: invokevirtual #56; //Method java/lang/StringBuilder.toString:()Ljava/lang/String; 133: invokevirtual #61; //Method java/io/PrintStream.println:(Ljava/lang/String;)V 136: return private int foo(int); Code: 0: iload_1 1: ireturn private static final int foo_aroundBody0(BugExample, BugExample, int); Code: 0: aload_1 1: iload_2 2: invokespecial #26; //Method foo:(I)I 5: ireturn private static final int foo_aroundBody1$advice(BugExample, BugExample, int, BugExample$BugAspect, int, org.aspectj.runtime.internal.AroundClosure); Code: 0: iload 4 2: ifle 21 5: iload 4 7: aload 5 9: astore 6 11: istore 7 13: aload_0 14: aload_1 15: iload 7 17: invokestatic #90; //Method foo_aroundBody0:(LBugExample;LBugExample;I)I 20: ireturn 21: iconst_0 22: ireturn private static final int foo_aroundBody2(BugExample, BugExample, int); Code: 0: aload_1 1: iload_2 2: invokespecial #26; //Method foo:(I)I 5: ireturn private static final int foo_aroundBody3$advice(BugExample, BugExample, int, BugExample$BugAspect, int, org.aspectj.runtime.internal.AroundClosure); Code: 0: iload 4 2: ifle 21 5: iload 4 7: aload 5 9: astore 6 11: istore 7 13: aload_0 14: aload_1 15: iload 7 17: invokestatic #96; //Method foo_aroundBody2:(LBugExample;LBugExample;I)I 20: ireturn 21: iconst_0 22: ireturn private static final int foo_aroundBody4(BugExample, BugExample, int); Code: 0: aload_1 1: iload_2 2: invokespecial #26; //Method foo:(I)I 5: ireturn private static final int foo_aroundBody5$advice(BugExample, BugExample, int, BugExample$BugAspect, int, org.aspectj.runtime.internal.AroundClosure); Code: 0: iload 4 2: ifle 21 5: iload 4 7: aload 5 9: astore 6 11: istore 7 13: aload_0 14: aload_1 15: iload 7 17: invokestatic #102; //Method foo_aroundBody4:(LBugExample;LBugExample;I)I 20: ireturn 21: iconst_0 22: ireturn private static final int foo_aroundBody6(BugExample, BugExample, int); Code: 0: aload_1 1: iload_2 2: invokespecial #26; //Method foo:(I)I 5: ireturn private static final int foo_aroundBody7$advice(BugExample, BugExample, int, BugExample$BugAspect, int, org.aspectj.runtime.internal.AroundClosure); Code: 0: iload 4 2: ifle 21 5: iload 4 7: aload 5 9: astore 6 11: istore 7 13: aload_0 14: aload_1 15: iload 7 17: invokestatic #108; //Method foo_aroundBody6:(LBugExample;LBugExample;I)I 20: ireturn 21: iconst_0 22: ireturn }
I forgot to mention that the javap command was run after compiling the code with ajc1.5.2, provided with AJDT 1.4 for Eclipse 3.2.
worth a try getting this into 1.5.3
Decompiling the provided testcase with "javap -private -verbose BugExample" shows that the LineNumberTables are different.
(In reply to comment #3) Indeed, the LineNumberTables for shadow methods are different, since they refer to different shadows. So this affects debugging, since the same instruction can't refer to several source-code lines. Can the repeated methods still be applied if line number information is not generated? (or more specifically, if debug is disabled?)
unsetting the target field which is currently set for something already released
