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Using AspectJ 1.1.0 on Windows, if I create an aspect that contains a declaration of an empty interface "I" and then supply a default implementation of the clone() method for the interface then an internal compiler error occurs at build time. Here is the simplest test case I can make :- public aspect MyAspectA { protected interface I {} public Object I.clone() throws CloneNotSupportedException { return super.clone(); } } When I run ajc against the above class I get the following output .. java.lang.NullPointerException at org.eclipse.jdt.internal.compiler.ast.MessageSend.analyseCode(MessageSend. java:40) at org.eclipse.jdt.internal.compiler.ast.ReturnStatement. analyseCode(ReturnStatement.java:37) at org.eclipse.jdt.internal.compiler.ast.MethodDeclaration. analyseCode(MethodDeclaration.java:70) at org.aspectj.ajdt.internal.compiler.ast.InterTypeMethodDeclaration. analyseCode(InterTypeMethodDeclaration.java:58) at org.eclipse.jdt.internal.compiler.ast.TypeDeclaration. internalAnalyseCode(TypeDeclaration.java:639) at org.eclipse.jdt.internal.compiler.ast.TypeDeclaration. analyseCode(TypeDeclaration.java:196) at org.eclipse.jdt.internal.compiler.ast.CompilationUnitDeclaration. analyseCode(CompilationUnitDeclaration.java:78) at org.eclipse.jdt.internal.compiler.Compiler.process(Compiler.java:541) at org.aspectj.ajdt.internal.compiler.AjCompiler.process(AjCompiler.java:65) at org.eclipse.jdt.internal.compiler.Compiler.compile(Compiler.java:338) at org.aspectj.ajdt.internal.core.builder.AjBuildManager. performCompilation(AjBuildManager.java:372) at org.aspectj.ajdt.internal.core.builder.AjBuildManager.doBuild(AjBuildManager. java:133) at org.aspectj.ajdt.internal.core.builder.AjBuildManager. batchBuild(AjBuildManager.java:78) at org.aspectj.ajdt.ajc.AjdtCommand.doCommand(AjdtCommand.java:106) at org.aspectj.ajdt.ajc.AjdtCommand.runCommand(AjdtCommand.java:60) at org.aspectj.tools.ajc.Main.run(Main.java:217) at org.aspectj.tools.ajc.Main.runMain(Main.java:155) at org.aspectj.tools.ajc.Main.main(Main.java:72) Please note that I have run the same aspect through the 1.0.6 AspectJ compiler without any problems.
Forgot to mention in my original report that if the single line of code inside the clone() method (return super.clone()) is replaced with the line "return null" then the aspect will compile OK on 1.1.0.
General form of the bug is whenever Object methods are called from methods introduced on an interface. *** This bug has been marked as a duplicate of 39993 ***
Here are two related patches that add a test for this problem to the AspectJ testing harness. I've had to split the patch into two because with all of the . ajesym files that were created in my workspace from running the tests my first pass at a patch was too big to paste into this note. Patch 1 of 2 ----------------- Index: georgeTests.xml =================================================================== RCS file: georgeTests.xml diff -N georgeTests.xml --- /dev/null 1 Jan 1970 00:00:00 -0000 +++ georgeTests.xml 23 Jul 2003 10:25:54 -0000 @@ -0,0 +1,9 @@ +<!DOCTYPE suite SYSTEM "../tests/ajcTestSuite.dtd"> +<suite> + <ajc-test dir="bugs" pr="40589" + title="Default method impl for interface causes internal exception."> + <compile files="CloneMethod.java"/> + <run class="CloneMethod"/> + </ajc-test> + +</suite> \ No newline at end of file Patch 2 of 2 ----------------- Index: CloneMethod.java =================================================================== RCS file: CloneMethod.java diff -N CloneMethod.java --- /dev/null 1 Jan 1970 00:00:00 -0000 +++ CloneMethod.java 23 Jul 2003 10:26:38 -0000 @@ -0,0 +1,58 @@ +aspect AspectA { + protected interface I { + } + + declare parents : MyString implements I; + + protected Object createCloneFor(I object) { + if (object instanceof MyString) { + return new MyString(((MyString) object).toString()); + } else { + return null; + } + } + + public Object I.clone() throws CloneNotSupportedException { + return super.clone(); +// return null; + } + + public Object cloneObject(I object) { + try { + return object.clone(); + } catch (CloneNotSupportedException ex) { + return createCloneFor(object); + } + } +} + +class MyString implements Cloneable { + + protected String text; + + public MyString(String init) { + text = init; + } + + public void setText(String newText) { + text = newText; + } + + public String toString() { + return "MyString: " + text; + } +} + +public class CloneMethod { + + public static void main(String[] args) { + MyString orig1; + MyString copy1; + + orig1 = new MyString(" This is I 1"); + copy1 = (MyString) AspectA.aspectOf().cloneObject(orig1); + orig1.setText(" This is I 2"); + copy1.setText(" This is Clone 1"); + System.out.println("... done."); + } +}
Great. This test has been added to the tree, and it also passes with the existing fix. This patch was extremely easy to apply. Only one comment. For patches that you submit, you should put the test case in either ajcTests.xml or ajcTestsFailing.xml depending on the status rather than creating a new file. jimTests.xml is a convenience file that I use locally for playing around with things. I'm going to remove it from the tree so that it won't confuse others in the future.
