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Build Identifier: I20100603-1500 Running an annotation processor, I'm getting the following stack trace while calling TypeMirror.toString(): java.lang.NullPointerException at org.eclipse.jdt.internal.compiler.lookup.ParameterizedTypeBinding.readableName(ParameterizedTypeBinding.java:828) at org.eclipse.jdt.internal.compiler.lookup.ParameterizedTypeBinding.readableName(ParameterizedTypeBinding.java:836) at org.eclipse.jdt.internal.compiler.apt.model.DeclaredTypeImpl.toString(DeclaredTypeImpl.java:123) at org.bindgen.processor.util.BoundProperty.<init>(BoundProperty.java:51) at org.bindgen.processor.generators.MethodPropertyGenerator.<init>(MethodPropertyGenerator.java:41) at org.bindgen.processor.generators.MethodPropertyGenerator$Factory.newGenerator(MethodPropertyGenerator.java:260) at org.bindgen.processor.generators.MethodPropertyGenerator$Factory.newGenerator(MethodPropertyGenerator.java:229) at org.bindgen.processor.generators.BindingClassGenerator.getPropertyGenerators(BindingClassGenerator.java:184) at org.bindgen.processor.generators.BindingClassGenerator.addProperties(BindingClassGenerator.java:119) at org.bindgen.processor.generators.BindingClassGenerator.generate(BindingClassGenerator.java:62) at org.bindgen.processor.GenerationQueue.processQueue(GenerationQueue.java:65) at org.bindgen.processor.Processor.process(Processor.java:67) at org.eclipse.jdt.internal.compiler.apt.dispatch.RoundDispatcher.handleProcessor(RoundDispatcher.java:139) at org.eclipse.jdt.internal.compiler.apt.dispatch.RoundDispatcher.round(RoundDispatcher.java:121) at org.eclipse.jdt.internal.compiler.apt.dispatch.BaseAnnotationProcessorManager.processAnnotations(BaseAnnotationProcessorManager.java:159) at org.eclipse.jdt.internal.apt.pluggable.core.dispatch.IdeAnnotationProcessorManager.processAnnotations(IdeAnnotationProcessorManager.java:134) at org.eclipse.jdt.internal.compiler.Compiler.processAnnotations(Compiler.java:809) at org.eclipse.jdt.internal.compiler.Compiler.compile(Compiler.java:428) at org.eclipse.jdt.internal.core.builder.AbstractImageBuilder.compile(AbstractImageBuilder.java:364) at org.eclipse.jdt.internal.core.builder.BatchImageBuilder.compile(BatchImageBuilder.java:178) at org.eclipse.jdt.internal.core.builder.AbstractImageBuilder.compile(AbstractImageBuilder.java:301) at org.eclipse.jdt.internal.core.builder.BatchImageBuilder.build(BatchImageBuilder.java:60) at org.eclipse.jdt.internal.core.builder.JavaBuilder.buildAll(JavaBuilder.java:254) at org.eclipse.jdt.internal.core.builder.JavaBuilder.build(JavaBuilder.java:173) at org.eclipse.core.internal.events.BuildManager$2.run(BuildManager.java:629) at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42) at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:172) at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:203) at org.eclipse.core.internal.events.BuildManager$1.run(BuildManager.java:255) at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42) at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:258) at org.eclipse.core.internal.events.BuildManager.basicBuildLoop(BuildManager.java:311) at org.eclipse.core.internal.events.BuildManager.build(BuildManager.java:343) at org.eclipse.core.internal.events.AutoBuildJob.doBuild(AutoBuildJob.java:144) at org.eclipse.core.internal.events.AutoBuildJob.run(AutoBuildJob.java:242) at org.eclipse.core.internal.jobs.Worker.run(Worker.java:54) The line that is failing is enclosingType().readableName(): public char[] readableName() { StringBuffer nameBuffer = new StringBuffer(10); if (isMemberType()) { nameBuffer.append(CharOperation.concat(enclosingType().readableName(), this.sourceName, '.')); } else { nameBuffer.append(CharOperation.concatWith(this.type.compoundName, '.')); } isMemberType() is true but the enclosingType field is null. The error is happening with: * TypeElement te = java.util.Map * ExecutableElement ee = te.getEnclosed() if kind==name and name==entrySet * TypeMirror tm = ee.getReturnType * tm.toString() --> NPE Note that tm is the DeclaredTypeImpl that is 3 lines into the NPE stack trace. While tm.toString() fails (it calls _binding.readableName()), if I debug and look at _binding, it toStrings() as: public interface Set<Entry<K,V>> extends NULL TYPENULL SUPERINTERFACESNULL FIELDSNULL METHODS Inside the _binding.readableName, nameBuffer had gotten to: java.util.Set< And it is calling into the 1st type parameters readableName. This binding can also toString: public static interface Entry<K,V> extends NULL TYPENULL SUPERINTERFACESNULL FIELDSNULL METHODS But it's readableName is what is blowing up. I've made a separate project to reproduce it, but unfortunately it works just fine. I get to the same binding, and in this new project it toStrings as: public static interface Entry<K,V> extends NULL TYPENULL SUPERINTERFACES enclosing type : Map#RAWNULL FIELDSNULL METHODS Note that enclosign type is no longer null. I have no idea why my more complex project would lead to the enclosing type being null. I can keep poking around, but suggestions are welcome. Also note that I'm seeing this behavior in both the latest 3.5 and 3.6.RC4. Reproducible: Always Steps to Reproduce: I cannot reproduce it outside of my current project yet.
I can't get this out into a sample project, but it's easily reproducible in my existing project. If you checkout bindgen from github, this commit introduces the error: http://github.com/stephenh/bindgen/commit/5f4d0feddf5789088c9c8f3618c1a7f0089018c0 Bindgen comes with two projects, the processor which you can import into Eclipse and then run the BindgenExamples launch target in debug mode and import the bindgen-examples project. If you set a debug point for NPE and then change/save the MapFailsExample class in the bindgen-examples, you should hit the error right away. Commenting/uncommenting the Map<String,String> line from the MapFailsExample class makes it go away/come back. I've tried to mimic the bindgen processor's call path as closely as possible in another project to recreate the error and have not had success yet.
Still no luck reproducing--I'd really like to set a conditional breakpoint in ParameterizedTypeBinding to see when it's constructed such that isMemberType==true but enclosingType==null. My eclipse setup isn't letting me do that though, I can set breakpoints but conditional ones cause a "missing Java project context" error.
Created attachment 172292 [details] reproduction of NPE Got it. Should have found it a lot sooner. The culprit is the Types method: DeclaredType getDeclaredType(TypeElement typeElem, TypeMirror... typeArgs); The bindgen processor does this dance where if we're in a type Foo<T> and a method return type is List<T>, but the user has declared their field as Foo<String> someStrings, I have this crazy look up routine where I figure out that the T in List<T> is the same type as Foo<T> and so then get the declared type of Foo with String, e.g. getDeclaredType(Foo, new TypeMirror[] { String }). It turns out when the type var is not resolved, as in the case of Map.Entry<K, V>, and I call getDeclaredType(Map.Entry, new TypeMirror{} { K, V }), the resulting DeclaredType has the faulty memberType==true but enclosing==null. (There are probably a few inaccuracies in my description, I'm rushing it, but nonetheless the attached file reproduces the error.) Now that I know what is going wrong, I could potentially avoid it--if I detect that no s/T/String replacement took place, I could skip the getDeclaredType(Foo, TypeMirror[]) and just use the original Foo TypeMirror.
Hi, is there any news on this? Correct me if I'm wrong, but it still seems to be present in 4.6M6. Thanks.
*** Bug 497522 has been marked as a duplicate of this bug. ***
New Gerrit change created: https://git.eclipse.org/r/76903
One of my coworkers suggested the following fix (attached).
Thanks everyone, patch released here: http://git.eclipse.org/c/jdt/eclipse.jdt.core.git/commit/?id=225d59ef8bf19c3509603a756a5a06ed9b38fadd And test here: http://git.eclipse.org/c/jdt/eclipse.jdt.core.git/commit/?id=8c20364cec20db9df028ee3c438a99040d64efe6
Awesome!
