Comments on: Feedback regarding Java ‘yield’ http://chaoticjava.com/posts/feedback-regarding-java-yield/ The internet, design patterns, frameworks and Java Wed, 08 Sep 2010 10:18:29 -0700 hourly 1 http://wordpress.org/?v=3.0.1 By: Chaotic Java » Yielder: Eclipse bug revealed, newsgroup created http://chaoticjava.com/posts/feedback-regarding-java-yield/comment-page-1/#comment-7948 Chaotic Java » Yielder: Eclipse bug revealed, newsgroup created Sun, 19 Aug 2007 04:06:13 +0000 http://chaoticjava.com/posts/feedback-regarding-java-yield/#comment-7948 [...] For some people the Yielder test cases didn’t pass properly. Readers Hanson Char and Michael Barker found a bug, which is either caused by the different OS used or the different compiler used (Windows vs. Linux/Mac, or Eclipse vs. Sun/Apple compiler). [...] [...] For some people the Yielder test cases didn’t pass properly. Readers Hanson Char and Michael Barker found a bug, which is either caused by the different OS used or the different compiler used (Windows vs. Linux/Mac, or Eclipse vs. Sun/Apple compiler). [...]

]]> By: Avah http://chaoticjava.com/posts/feedback-regarding-java-yield/comment-page-1/#comment-7947 Avah Sun, 19 Aug 2007 03:38:18 +0000 http://chaoticjava.com/posts/feedback-regarding-java-yield/#comment-7947 Wow, thanks! Can you describe the bug in the issues section of the project? Wow, thanks! Can you describe the bug in the issues section of the project?

]]> By: Michael Barker http://chaoticjava.com/posts/feedback-regarding-java-yield/comment-page-1/#comment-7921 Michael Barker Sat, 18 Aug 2007 21:16:13 +0000 http://chaoticjava.com/posts/feedback-regarding-java-yield/#comment-7921 Okay, figured it out. It is caused by the eclipse compiler. It generates slightly different bytecode for the foreach loop to the sun compiler. I.e. with the eclipse compiler it does not trigger local variable declarations, therefore when searchMember is called on the LocalVariableMapper, it can't "see" the generated variables. I can work around this. As I figure out the code I will try to put together a patch. Mike Okay, figured it out. It is caused by the eclipse compiler. It generates slightly different bytecode for the foreach loop to the sun compiler. I.e. with the eclipse compiler it does not trigger local variable declarations, therefore when searchMember is called on the LocalVariableMapper, it can’t “see” the generated variables.

I can work around this. As I figure out the code I will try to put together a patch.

Mike

]]> By: Avah http://chaoticjava.com/posts/feedback-regarding-java-yield/comment-page-1/#comment-7918 Avah Sat, 18 Aug 2007 19:03:07 +0000 http://chaoticjava.com/posts/feedback-regarding-java-yield/#comment-7918 There was an issue with "foreach" style loops when nested. The problem was that the compiled iterators (i$, usually) had the same name in different scopes, something I did not anticipate. That bug was fixed, but there might be others. You might be interested in the previous one's details <a href="http://code.google.com/p/infomancers-collections/issues/detail?id=5&can=1" rel="nofollow">here</a>. If you're already debugging (and thank you very much for that!), try to verify it happens in normal, non-nested loops as well. It really narrows the problem down. There was an issue with “foreach” style loops when nested. The problem was that the compiled iterators (i$, usually) had the same name in different scopes, something I did not anticipate.

That bug was fixed, but there might be others. You might be interested in the previous one’s details here.

If you’re already debugging (and thank you very much for that!), try to verify it happens in normal, non-nested loops as well. It really narrows the problem down.

]]> By: Michael Barker http://chaoticjava.com/posts/feedback-regarding-java-yield/comment-page-1/#comment-7917 Michael Barker Sat, 18 Aug 2007 18:58:13 +0000 http://chaoticjava.com/posts/feedback-regarding-java-yield/#comment-7917 It seems to be related to foreach style for loop. I changed it too a started for loop using a index int and it worked. I'm going to continue debugging. It seems to be related to foreach style for loop. I changed it too a started for loop using a index int and it worked.

I’m going to continue debugging.

]]> By: Avah http://chaoticjava.com/posts/feedback-regarding-java-yield/comment-page-1/#comment-7914 Avah Sat, 18 Aug 2007 18:15:19 +0000 http://chaoticjava.com/posts/feedback-regarding-java-yield/#comment-7914 Since I didn't get the chance of debugging into it yet (apparently it's an OS issue of some sort), would you say that it's a matter of nested loops or any loops? The idea for a google group is a good one. I'll start one and post about it soon. Since I didn’t get the chance of debugging into it yet (apparently it’s an OS issue of some sort), would you say that it’s a matter of nested loops or any loops?

The idea for a google group is a good one. I’ll start one and post about it soon.

]]> By: Michael Barker http://chaoticjava.com/posts/feedback-regarding-java-yield/comment-page-1/#comment-7910 Michael Barker Sat, 18 Aug 2007 17:08:50 +0000 http://chaoticjava.com/posts/feedback-regarding-java-yield/#comment-7910 Hi, I am really interested in using this tool. I am running into the error mentioned in the first blog post using the code from SVN. It seems to struggle with yields within loops. Would you consider creating a google group for discussions around Yielder? Mike. Hi,

I am really interested in using this tool. I am running into the error mentioned in the first blog post using the code from SVN. It seems to struggle with yields within loops.

Would you consider creating a google group for discussions around Yielder?

Mike.

]]> By: Hanson Char http://chaoticjava.com/posts/feedback-regarding-java-yield/comment-page-1/#comment-7670 Hanson Char Tue, 14 Aug 2007 17:37:16 +0000 http://chaoticjava.com/posts/feedback-regarding-java-yield/#comment-7670 >it worked when I ran it with the junit test I meant when I ran it with the junit test from within Eclipse 3.1.2. >it worked when I ran it with the junit test

I meant when I ran it with the junit test from within Eclipse 3.1.2.

]]> By: Hanson Char http://chaoticjava.com/posts/feedback-regarding-java-yield/comment-page-1/#comment-7669 Hanson Char Tue, 14 Aug 2007 17:35:58 +0000 http://chaoticjava.com/posts/feedback-regarding-java-yield/#comment-7669 The JUnit didn't work and that's what motivated me to put in a simple main method in the 1st place. I tried the javaagent:yielder-0.1.1.jar=debug, it didn't make a difference on the command line, but it worked when I ran it with the junit test. The complete output is pretty verbose. I can post it here, but probably less of a nuisance if I emailed to you, but I don't know your email address. So just post an fragment below. Hope that helps. // class version 49.0 (49) // access flags 48 // signature Lcom/infomancers/collections/yield/Yielder; // declaration: com/infomancers/tests/YielderTests$3 extends com.infomancers.collections.yield.Yielder final class com/infomancers/tests/YielderTests$3 extends com/infomancers/collections/yield/Yielder { // compiled from: YielderTests.java OUTERCLASS com/infomancers/tests/YielderTests someStrings ()V // access flags 18 private final INNERCLASS com/infomancers/tests/YielderTests$3 null null // access flags 4112 final Lcom/infomancers/tests/YielderTests; this$0 // access flags 0 (Lcom/infomancers/tests/YielderTests;)V L0 LINENUMBER 1 L0 ALOAD 0 ALOAD 1 PUTFIELD com/infomancers/tests/YielderTests$3.this$0 : Lcom/infomancers/tests/YielderTests; L1 LINENUMBER 71 L1 ALOAD 0 INVOKESPECIAL com/infomancers/collections/yield/Yielder. ()V RETURN L2 LOCALVARIABLE this Lcom/infomancers/tests/YielderTests$3; L0 L2 0 MAXSTACK = 2 MAXLOCALS = 2 // access flags 4 protected yieldNextCore()V L0 LINENUMBER 74 L0 ALOAD 0 LDC "This" INVOKEVIRTUAL com/infomancers/tests/YielderTests$3.yieldReturn (Ljava/lang/Object;)V L1 LINENUMBER 75 L1 ALOAD 0 LDC "Is" INVOKEVIRTUAL com/infomancers/tests/YielderTests$3.yieldReturn (Ljava/lang/Object;)V L2 LINENUMBER 76 L2 ALOAD 0 LDC "Great" INVOKEVIRTUAL com/infomancers/tests/YielderTests$3.yieldReturn (Ljava/lang/Object;)V L3 LINENUMBER 77 L3 RETURN L4 LOCALVARIABLE this Lcom/infomancers/tests/YielderTests$3; L0 L4 0 MAXSTACK = 2 MAXLOCALS = 1 } // class version 49.0 (49) // access flags 48 // signature Lcom/infomancers/collections/yield/Yielder; // declaration: com/infomancers/tests/YielderTests$3 extends com.infomancers.collections.yield.Yielder final class com/infomancers/tests/YielderTests$3 extends com/infomancers/collections/yield/Yielder { // compiled from: YielderTests.java OUTERCLASS com/infomancers/tests/YielderTests someStrings ()V // access flags 18 private final INNERCLASS com/infomancers/tests/YielderTests$3 null null // access flags 4112 final Lcom/infomancers/tests/YielderTests; this$0 // access flags 0 (Lcom/infomancers/tests/YielderTests;)V L0 LINENUMBER 1 L0 ALOAD 0 ALOAD 1 PUTFIELD com/infomancers/tests/YielderTests$3.this$0 : Lcom/infomancers/tests/YielderTests; L1 LINENUMBER 71 L1 ALOAD 0 INVOKESPECIAL com/infomancers/collections/yield/Yielder. ()V RETURN L2 LOCALVARIABLE this Lcom/infomancers/tests/YielderTests$3; L0 L2 0 MAXSTACK = 2 MAXLOCALS = 2 // access flags 4 protected yieldNextCore()V ALOAD 0 GETFIELD com/infomancers/tests/YielderTests$3.state : B TABLESWITCH 1: L0 2: L1 3: L2 default: L3 L3 L4 LINENUMBER 74 L4 ALOAD 0 LDC "This" INVOKEVIRTUAL com/infomancers/tests/YielderTests$3.yieldReturn (Ljava/lang/Object;)V ALOAD 0 BIPUSH 1 PUTFIELD com/infomancers/tests/YielderTests$3.state : B RETURN L0 L5 LINENUMBER 75 L5 ALOAD 0 LDC "Is" INVOKEVIRTUAL com/infomancers/tests/YielderTests$3.yieldReturn (Ljava/lang/Object;)V ALOAD 0 BIPUSH 2 PUTFIELD com/infomancers/tests/YielderTests$3.state : B RETURN L1 L6 LINENUMBER 76 L6 ALOAD 0 LDC "Great" INVOKEVIRTUAL com/infomancers/tests/YielderTests$3.yieldReturn (Ljava/lang/Object;)V ALOAD 0 BIPUSH 3 PUTFIELD com/infomancers/tests/YielderTests$3.state : B RETURN L2 L7 LINENUMBER 77 L7 RETURN L8 LOCALVARIABLE this Lcom/infomancers/tests/YielderTests$3; L4 L8 0 MAXSTACK = 2 MAXLOCALS = 1 // access flags 2 // signature Lcom/infomancers/tests/YielderTests$3; // declaration: com.infomancers.tests.YielderTests$3 private Lcom/infomancers/tests/YielderTests$3; this$promoted$0$4 // access flags 2 // signature B // declaration: byte private B state } java.util.NoSuchElementException at java.util.LinkedList.remove(LinkedList.java:788) at java.util.LinkedList.removeFirst(LinkedList.java:134) at java.util.LinkedList.remove(LinkedList.java:481) at com.infomancers.collections.yield.asm.LocalVariablePromoter$MyMethodAdapter.dealWithLoads(LocalVariablePromoter.java:125) at com.infomancers.collections.yield.asm.LocalVariablePromoter$MyMethodAdapter.visitLabel(LocalVariablePromoter.java:103) at org.objectweb.asm.ClassReader.accept(Unknown Source) at org.objectweb.asm.ClassReader.accept(Unknown Source) at com.infomancers.collections.yield.asm.YielderTransformer.enhanceClass(YielderTransformer.java:112) at com.infomancers.collections.yield.asm.YielderTransformer.transform(YielderTransformer.java:88) at sun.instrument.TransformerManager.transform(TransformerManager.java:169) at sun.instrument.InstrumentationImpl.transform(InstrumentationImpl.java:365) at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(ClassLoader.java:620) at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124) at java.net.URLClassLoader.defineClass(URLClassLoader.java:260) at java.net.URLClassLoader.access$000(URLClassLoader.java:56) at java.net.URLClassLoader$1.run(URLClassLoader.java:195) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:188) at java.lang.ClassLoader.loadClass(ClassLoader.java:306) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:276) at java.lang.ClassLoader.loadClass(ClassLoader.java:251) at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319) at com.infomancers.tests.YielderTests.someStrings(YielderTests.java:71) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at org.junit.internal.runners.TestMethodRunner.executeMethodBody(TestMethodRunner.java:99) at org.junit.internal.runners.TestMethodRunner.runUnprotected(TestMethodRunner.java:81) at org.junit.internal.runners.BeforeAndAfterRunner.runProtected(BeforeAndAfterRunner.java:34) at org.junit.internal.runners.TestMethodRunner.runMethod(TestMethodRunner.java:75) at org.junit.internal.runners.TestMethodRunner.run(TestMethodRunner.java:45) at org.junit.internal.runners.TestClassMethodsRunner.invokeTestMethod(TestClassMethodsRunner.java:71) at org.junit.internal.runners.TestClassMethodsRunner.run(TestClassMethodsRunner.java:35) at org.junit.internal.runners.TestClassRunner$1.runUnprotected(TestClassRunner.java:42)// class version 49.0 (49) The JUnit didn’t work and that’s what motivated me to put in a simple main method in the 1st place.

I tried the javaagent:yielder-0.1.1.jar=debug, it didn’t make a difference on the command line, but it worked when I ran it with the junit test.

The complete output is pretty verbose. I can post it here, but probably less of a nuisance if I emailed to you, but I don’t know your email address. So just post an fragment below. Hope that helps.

// class version 49.0 (49)
// access flags 48
// signature Lcom/infomancers/collections/yield/Yielder;
// declaration: com/infomancers/tests/YielderTests$3 extends com.infomancers.collections.yield.Yielder
final class com/infomancers/tests/YielderTests$3 extends com/infomancers/collections/yield/Yielder {

// compiled from: YielderTests.java
OUTERCLASS com/infomancers/tests/YielderTests someStrings ()V
// access flags 18
private final INNERCLASS com/infomancers/tests/YielderTests$3 null null

// access flags 4112
final Lcom/infomancers/tests/YielderTests; this$0

// access flags 0
(Lcom/infomancers/tests/YielderTests;)V
L0
LINENUMBER 1 L0
ALOAD 0
ALOAD 1
PUTFIELD com/infomancers/tests/YielderTests$3.this$0 : Lcom/infomancers/tests/YielderTests;
L1
LINENUMBER 71 L1
ALOAD 0
INVOKESPECIAL com/infomancers/collections/yield/Yielder. ()V
RETURN
L2
LOCALVARIABLE this Lcom/infomancers/tests/YielderTests$3; L0 L2 0
MAXSTACK = 2
MAXLOCALS = 2

// access flags 4
protected yieldNextCore()V
L0
LINENUMBER 74 L0
ALOAD 0
LDC “This”
INVOKEVIRTUAL com/infomancers/tests/YielderTests$3.yieldReturn (Ljava/lang/Object;)V
L1
LINENUMBER 75 L1
ALOAD 0
LDC “Is”
INVOKEVIRTUAL com/infomancers/tests/YielderTests$3.yieldReturn (Ljava/lang/Object;)V
L2
LINENUMBER 76 L2
ALOAD 0
LDC “Great”
INVOKEVIRTUAL com/infomancers/tests/YielderTests$3.yieldReturn (Ljava/lang/Object;)V
L3
LINENUMBER 77 L3
RETURN
L4
LOCALVARIABLE this Lcom/infomancers/tests/YielderTests$3; L0 L4 0
MAXSTACK = 2
MAXLOCALS = 1
}
// class version 49.0 (49)
// access flags 48
// signature Lcom/infomancers/collections/yield/Yielder;
// declaration: com/infomancers/tests/YielderTests$3 extends com.infomancers.collections.yield.Yielder
final class com/infomancers/tests/YielderTests$3 extends com/infomancers/collections/yield/Yielder {

// compiled from: YielderTests.java
OUTERCLASS com/infomancers/tests/YielderTests someStrings ()V
// access flags 18
private final INNERCLASS com/infomancers/tests/YielderTests$3 null null

// access flags 4112
final Lcom/infomancers/tests/YielderTests; this$0

// access flags 0
(Lcom/infomancers/tests/YielderTests;)V
L0
LINENUMBER 1 L0
ALOAD 0
ALOAD 1
PUTFIELD com/infomancers/tests/YielderTests$3.this$0 : Lcom/infomancers/tests/YielderTests;
L1
LINENUMBER 71 L1
ALOAD 0
INVOKESPECIAL com/infomancers/collections/yield/Yielder. ()V
RETURN
L2
LOCALVARIABLE this Lcom/infomancers/tests/YielderTests$3; L0 L2 0
MAXSTACK = 2
MAXLOCALS = 2

// access flags 4
protected yieldNextCore()V
ALOAD 0
GETFIELD com/infomancers/tests/YielderTests$3.state : B
TABLESWITCH
1: L0
2: L1
3: L2
default: L3
L3
L4
LINENUMBER 74 L4
ALOAD 0
LDC “This”
INVOKEVIRTUAL com/infomancers/tests/YielderTests$3.yieldReturn (Ljava/lang/Object;)V
ALOAD 0
BIPUSH 1
PUTFIELD com/infomancers/tests/YielderTests$3.state : B
RETURN
L0
L5
LINENUMBER 75 L5
ALOAD 0
LDC “Is”
INVOKEVIRTUAL com/infomancers/tests/YielderTests$3.yieldReturn (Ljava/lang/Object;)V
ALOAD 0
BIPUSH 2
PUTFIELD com/infomancers/tests/YielderTests$3.state : B
RETURN
L1
L6
LINENUMBER 76 L6
ALOAD 0
LDC “Great”
INVOKEVIRTUAL com/infomancers/tests/YielderTests$3.yieldReturn (Ljava/lang/Object;)V
ALOAD 0
BIPUSH 3
PUTFIELD com/infomancers/tests/YielderTests$3.state : B
RETURN
L2
L7
LINENUMBER 77 L7
RETURN
L8
LOCALVARIABLE this Lcom/infomancers/tests/YielderTests$3; L4 L8 0
MAXSTACK = 2
MAXLOCALS = 1

// access flags 2
// signature Lcom/infomancers/tests/YielderTests$3;
// declaration: com.infomancers.tests.YielderTests$3
private Lcom/infomancers/tests/YielderTests$3; this$promoted$0$4

// access flags 2
// signature B
// declaration: byte
private B state
}
java.util.NoSuchElementException
at java.util.LinkedList.remove(LinkedList.java:788)
at java.util.LinkedList.removeFirst(LinkedList.java:134)
at java.util.LinkedList.remove(LinkedList.java:481)
at com.infomancers.collections.yield.asm.LocalVariablePromoter$MyMethodAdapter.dealWithLoads(LocalVariablePromoter.java:125)
at com.infomancers.collections.yield.asm.LocalVariablePromoter$MyMethodAdapter.visitLabel(LocalVariablePromoter.java:103)
at org.objectweb.asm.ClassReader.accept(Unknown Source)
at org.objectweb.asm.ClassReader.accept(Unknown Source)
at com.infomancers.collections.yield.asm.YielderTransformer.enhanceClass(YielderTransformer.java:112)
at com.infomancers.collections.yield.asm.YielderTransformer.transform(YielderTransformer.java:88)
at sun.instrument.TransformerManager.transform(TransformerManager.java:169)
at sun.instrument.InstrumentationImpl.transform(InstrumentationImpl.java:365)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:260)
at java.net.URLClassLoader.access$000(URLClassLoader.java:56)
at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:276)
at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
at com.infomancers.tests.YielderTests.someStrings(YielderTests.java:71)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.junit.internal.runners.TestMethodRunner.executeMethodBody(TestMethodRunner.java:99)
at org.junit.internal.runners.TestMethodRunner.runUnprotected(TestMethodRunner.java:81)
at org.junit.internal.runners.BeforeAndAfterRunner.runProtected(BeforeAndAfterRunner.java:34)
at org.junit.internal.runners.TestMethodRunner.runMethod(TestMethodRunner.java:75)
at org.junit.internal.runners.TestMethodRunner.run(TestMethodRunner.java:45)
at org.junit.internal.runners.TestClassMethodsRunner.invokeTestMethod(TestClassMethodsRunner.java:71)
at org.junit.internal.runners.TestClassMethodsRunner.run(TestClassMethodsRunner.java:35)
at org.junit.internal.runners.TestClassRunner$1.runUnprotected(TestClassRunner.java:42)// class version 49.0 (49)

]]> By: Avah http://chaoticjava.com/posts/feedback-regarding-java-yield/comment-page-1/#comment-7649 Avah Tue, 14 Aug 2007 07:36:58 +0000 http://chaoticjava.com/posts/feedback-regarding-java-yield/#comment-7649 Whoa! Did the JUnit itself work (after configuring it to run with the agent?) Also, can you please try to run it using -javaagent:yielder-0.1.1.jar=debug? it will output the bytecode (before and after the manipulation) and it will make it easier to debug. Whoa!

Did the JUnit itself work (after configuring it to run with the agent?)

Also, can you please try to run it using -javaagent:yielder-0.1.1.jar=debug? it will output the bytecode (before and after the manipulation) and it will make it easier to debug.

]]>