Hello Arrin, Thank you for your response. I found the method that fails and it's true that the bytecode resulting after compiling with the "-source 1.4" flag and the one that result when I compile with the "-source 1.5" are very different. Unfortunately for me, I don't have the skills required to judge what exactly triggers the exception I was talking about (I understand I try to pop from an empty stack but I haven't yet figured what exactly should be on that stack). I will post here the 2 bytecodes, hoping you or someone else would be able to detect the problem.
The bytecode that works (generated with "-source 1.4") is: public void _jistPostInit(); Code: 0: aload_0 1: getstatic #24; //Field jist/runtime/JistAPI.THIS:Ljist/runtime/JistAPI$Entity; 4: getstatic #25; //Field class$jist$swans$app$AppInterface$UdpApp:Ljava/lang/Class; 7: ifnonnull 22 10: ldc #26; //String jist.swans.app.AppInterface$UdpApp 12: invokestatic #27; //Method class$:(Ljava/lang/String;)Ljava/lang/Class; 15: dup 16: putstatic #25; //Field class$jist$swans$app$AppInterface$UdpApp:Ljava/lang/Class; 19: goto 25 22: getstatic #25; //Field class$jist$swans$app$AppInterface$UdpApp:Ljava/lang/Class; 25: invokestatic #28; //Method jist/runtime/JistAPI.proxy:(Ljava/lang/Object;Ljava/lang/Class;)Ljava/lang/Object; 28: checkcast #29; //class jist/swans/app/AppInterface$UdpApp 31: invokeinterface #30, 1; //InterfaceMethod jist/swans/app/AppInterface$UdpApp.getUdpEntity:()Ljist/swans/trans/TransInterface$TransUdpInterface; 36: putfield #31; //Field udpEntity:Ljist/swans/trans/TransInterface; 39: aload_0 40: new #6; //class java/net/InetSocketAddress 43: dup 44: aload_0 45: getfield #17; //Field laddr:Ljava/net/InetAddress; 48: aload_0 49: getfield #15; //Field lport:I 52: invokespecial #13; //Method java/net/InetSocketAddress."<init>":(Ljava/net/InetAddress;I)V 55: invokevirtual #32; //Method bind:(Ljava/net/SocketAddress;)V 58: return The one that fails, generated with "-source 1.5" is: public void _jistPostInit(); Code: 0: aload_0 1: getstatic #19; //Field jist/runtime/JistAPI.THIS:Ljist/runtime/JistAPI$Entity; 4: ldc_w #20; //class jist/swans/app/AppInterface$UdpApp 7: invokestatic #21; //Method jist/runtime/JistAPI.proxy:(Ljava/lang/Object;Ljava/lang/Class;)Ljava/lang/Object; 10: checkcast #20; //class jist/swans/app/AppInterface$UdpApp 13: invokeinterface #22, 1; //InterfaceMethod jist/swans/app/AppInterface$UdpApp.getUdpEntity:()Ljist/swans/trans/TransInterface$TransUdpInterface; 18: putfield #23; //Field udpEntity:Ljist/swans/trans/TransInterface; 21: aload_0 22: new #1; //class java/net/InetSocketAddress 25: dup 26: aload_0 27: getfield #12; //Field laddr:Ljava/net/InetAddress; 30: aload_0 31: getfield #10; //Field lport:I 34: invokespecial #8; //Method java/net/InetSocketAddress."<init>":(Ljava/net/InetAddress;I)V 37: invokevirtual #24; //Method bind:(Ljava/net/SocketAddress;)V 40: return The exception appears when the putfield operation is rewritten. Thank you once again for your answer, Razvan. Arrin Daley wrote: > > Hi > > My experience is that the error you are getting is it because some > method code has an invalid stack, in this case you are removing too many > items from the stack, the verifier is picking this up and reporting the > error. I'm not sure but perhaps some code doesn't call > MethodGen.setMaxStack() after transforming, although I doubt it, because > if the code were otherwise correct it should have complained of a stack > overflow. > > The problem has to be with the method it is verifying at the time so if > you can print out which method the verifier is working on and it's > bytecodes you could go through it and find the problem. The bytecode > pre-transformation by BCEL should be correct so the problem lies with > the transformations your code performs. > > I'm don't know why this should be a problem with 1.5 and not 1.4. > > Hope it helps > > Bye Arrin > > Razvanica wrote: >> Hello all, >> >> Here's my problem. I am trying to make some network simulations using a >> tool >> called JiST/SWANS. This simulator has been written for Java 1.4 and, for >> my >> simulations, I would like to use some 1.5 features, like genericity. >> >> So what I am trying to do is to compile the original code with the >> "source >> -1.5" tag instead of the "source -1.4" tag. The problem is that the >> simulator uses bcel to rewrite the bytecode so that JVM could be used for >> simulations. The bcel library in the release doesn't work with the >> "source >> -1.5" tag so I replace it with bcel-5.2. I made 2 minor modifications to >> the >> original code : >> - I have added an implementation of getClassPath in a class that >> implements >> org.apache.bcel.util.Repository. This class just returns null, just like >> in >> org.apache.bcel.util.ClassLoaderRepository >> - In a class using org.apache.bcel.Repository.lookupClass() I am now >> throwing java.lang.ClassNotFoundException >> >> These 2 modifications shouldn't change anything as far as I understand >> the >> application. And when I compile the new code with the "-source 1.4" tag, >> it >> doesn,t change anything. Everything compiles and works just fine. >> However, >> when I compile the new code with the "-source 1.5" tag the compilation >> goes >> smoothly, but, at runtime, the rewriter throws an >> ArrayIndexOutOfBoundsException. >> >> >> This happens every time org.apache.bcel.generic.PUTFIELD.accept is >> called: >> java.lang.ArrayIndexOutOfBoundsException: -1 >> at java.util.ArrayList.remove(ArrayList.java:390) >> at >> org.apache.bcel.verifier.structurals.OperandStack.pop(OperandStack.java:135) >> at >> org.apache.bcel.verifier.structurals.ExecutionVisitor.visitPUTFIELD(ExecutionVisitor.java:1048) >> at org.apache.bcel.generic.PUTFIELD.accept(PUTFIELD.java:78) >> >> Does anybody have any idea what happens and if there's something I could >> do >> to fix this? >> >> Thank you. >> > > --------------------------------------------------------------------- > To unsubscribe, e-mail: bcel-user-unsubscr...@jakarta.apache.org > For additional commands, e-mail: bcel-user-h...@jakarta.apache.org > > > -- View this message in context: http://www.nabble.com/ArrayIndexOutOfBoundsException-in-generic.PUTFIELD-tp23710707p23722920.html Sent from the BCEL - User mailing list archive at Nabble.com. --------------------------------------------------------------------- To unsubscribe, e-mail: bcel-user-unsubscr...@jakarta.apache.org For additional commands, e-mail: bcel-user-h...@jakarta.apache.org
