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My plugin crashed from an NPE when I called binding.getDeclaredMethods() on an anonymous type binding. The binding originates from a compilation unit with the following error: "This compilation unit indirectly references the missing type org.eclipse.swt.events.SelectionEvent (typically some required class file is referencing a type outside the classpath)" The NPE occurs at line 467 of MethodBinding because "scope" is null: AbstractMethodDeclaration[] methods = sourceType.scope.referenceContext.methods; Stack trace: java.lang.NullPointerException at org.eclipse.jdt.internal.compiler.lookup.MethodBinding.sourceMethod (MethodBinding.java:467) at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.resolveTypesFor (SourceTypeBinding.java:793) at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.methods (SourceTypeBinding.java:687) at org.eclipse.jdt.core.dom.TypeBinding.getDeclaredMethods(TypeBinding.java:324) at ca.ubc.jquery.engine.context.TypeContext.exitContext(TypeContext.java:117) at ca.ubc.jquery.engine.FactsGenerator.endVisit(FactsGenerator.java:50) at org.eclipse.jdt.core.dom.TypeDeclaration.accept0(TypeDeclaration.java:163) at org.eclipse.jdt.core.dom.ASTNode.accept(ASTNode.java:1353) at ca.ubc.jquery.engine.FactsGenerator.visit(FactsGenerator.java:42) at org.eclipse.jdt.core.dom.TypeDeclaration.accept0(TypeDeclaration.java:154) at org.eclipse.jdt.core.dom.ASTNode.accept(ASTNode.java:1353) at org.eclipse.jdt.core.dom.ASTNode.acceptChildren(ASTNode.java:1423) at org.eclipse.jdt.core.dom.CompilationUnit.accept0(CompilationUnit.java:159) at org.eclipse.jdt.core.dom.ASTNode.accept(ASTNode.java:1353) at ca.ubc.jquery.engine.FactsGenerator.generate(FactsGenerator.java:417) at ca.ubc.jquery.engine.CodeFactBucket.update(CodeFactBucket.java:543) at tyRuBa.engine.RuleBaseBucket.doUpdate(RuleBaseBucket.java:95) at tyRuBa.engine.FrontEnd.updateBuckets(FrontEnd.java:272) at tyRuBa.engine.FrontEnd.autoUpdateBuckets(FrontEnd.java:295) at tyRuBa.engine.QueryEngine.frameQuery(QueryEngine.java:89) at ca.ubc.jquery.gui.QueryControl.addAvailableTopQueries(QueryControl.java:333) at ca.ubc.jquery.gui.QueryControl.addTopQueryItems(QueryControl.java:500) at ca.ubc.jquery.gui.QueryControl.fillContextMenu(QueryControl.java:494) at ca.ubc.jquery.gui.QueryControl$9.menuAboutToShow(QueryControl.java:566) at org.eclipse.jface.action.MenuManager.fireAboutToShow(MenuManager.java:255) at org.eclipse.jface.action.MenuManager.handleAboutToShow(MenuManager.java:334) at org.eclipse.jface.action.MenuManager.access$0(MenuManager.java:331) at org.eclipse.jface.action.MenuManager$2.menuShown(MenuManager.java:343) at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:116) at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:81) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:840) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:865) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:845) at org.eclipse.swt.widgets.Control.WM_INITMENUPOPUP(Control.java:3141) at org.eclipse.swt.widgets.Control.windowProc(Control.java:2785) at org.eclipse.swt.widgets.Decorations.windowProc(Decorations.java:1229) at org.eclipse.swt.widgets.Display.windowProc(Display.java:2361) at org.eclipse.swt.internal.win32.OS.TrackPopupMenu(Native Method) at org.eclipse.swt.widgets.Menu._setVisible(Menu.java:218) at org.eclipse.swt.widgets.Display.runPopups(Display.java:1863) at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:1538) at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:1402) at org.eclipse.ui.internal.Workbench.run(Workbench.java:1385) at org.eclipse.core.internal.boot.InternalBootLoader.run (InternalBootLoader.java:845) at org.eclipse.core.boot.BootLoader.run(BootLoader.java:461) 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:324) at org.eclipse.core.launcher.Main.basicRun(Main.java:291) at org.eclipse.core.launcher.Main.run(Main.java:747) at org.eclipse.core.launcher.Main.main(Main.java:583)
Please provide a test case. I will investigate.
I tried the following test case: package test0489; public class A { Object foo () { return new Y() { public void bar() { } }; } } Where Y implements Zork and I remove the .class file for Zork. I get a similar error, but I can successfully get the declared methods. Could you please provide your test case for further investigation?
Could you please provide your test case or let me know where I can get your plugin? What build are you using?
I am using Eclipse: Version: 2.1.0, Build id: 200303272130 I zipped the problematic project and emailed it to you directly.
I reproduced it. Thanks for the test case. The problem is that an abortCompilation exception is thrown during the import resolution because of the missing library (swt.jar). Then the types are not resolved and the method declarations have no resolved bindings. Because the scope has been nullified during the compilation unit cleanup, it is not possible to resolve the bindings afterwards. So in this case, I think it is acceptable that no binding is returned for unresolved code. The classpath needs to be fixed in order to resolve properly all bindings. The specs say that if a binding cannot be resolved, null can be returned. In your case, the bug was that we didn't detect early enough that the bindings could not be resolved because of a failure during the import resolution. Is this ok for you?
Yes. I would definately prefer a null return value over a null pointer exception.
The fix will be to nullify all bindings that are not resolved. In this case you won't get a binding for the type declaration. Your test case is a case where there is a problem with the import declarations. Therefore all declarations underneath are not resolvable. According to the specs of the DOM/AST, it is acceptable in this case to return null for all bindings. I am testing my fix and I will release it shortly in HEAD.
Fixed and released in HEAD. Regression tests added.
Verified.
