NPE in spoon.support.compiler.jdt.ReferenceBuilder.tryRecoverTypeArguments(ReferenceBuilder.java:611)

[Strum355]

In a code sample similar to the following:

Code sample

private GrpcToReactorMethodBinding findReactorMethod(MethodDescriptor<?, ?> methodDescriptor) {
        // ...

        // Check method arguments
        if (reactorMethod.getParameterCount() == 0) {
            // ...
            return new GrpcToReactorMethodBinding<>(methodDescriptor, reactorMethod, -1, isMono, returnTypeParameter);
        }
	// ...
}

a NPE is thrown on ReferenceBuilder.java:611 as ParameterizedTypeBinding.typeArguments is a null array, with alloc.sourceStart pointing to the start of the new keyword.

Excerpt of GrpcToReactorMethodBinding is as follows:

GrpcToReactorMethodBinding code

class GrpcToReactorMethodBinding<REQ, RESP> {

    // ...

    GrpcToReactorMethodBinding(MethodDescriptor<REQ, RESP> methodDescriptor,
                               Method reactorMethod,
                               int callMetadataPos,
                               boolean isMono,
                               Class returnTypeParameter) {
		// ...
    }
	// ...
}

Stacktrace

Exception in thread "main" java.lang.NullPointerException: Cannot read the array length because "<local5>" is null
	at spoon.support.compiler.jdt.ReferenceBuilder.tryRecoverTypeArguments(ReferenceBuilder.java:611)
	at spoon.support.compiler.jdt.ReferenceBuilder.insertGenericTypesInNoClasspathFromJDTInSpoon(ReferenceBuilder.java:575)
	at spoon.support.compiler.jdt.ReferenceBuilder.getTypeReference(ReferenceBuilder.java:517)
	at spoon.support.compiler.jdt.ReferenceBuilder.buildTypeReference(ReferenceBuilder.java:136)
	at spoon.support.compiler.jdt.ReferenceBuilder.buildTypeReference(ReferenceBuilder.java:130)
	at spoon.support.compiler.jdt.JDTTreeBuilder.createParameterizedType(JDTTreeBuilder.java:1450)
	at spoon.support.compiler.jdt.JDTTreeBuilder.visit(JDTTreeBuilder.java:1438)
	at org.eclipse.jdt.internal.compiler.ast.ParameterizedSingleTypeReference.traverse(ParameterizedSingleTypeReference.java:405)
	at org.eclipse.jdt.internal.compiler.ast.AllocationExpression.traverse(AllocationExpression.java:713)
	at org.eclipse.jdt.internal.compiler.ast.ReturnStatement.traverse(ReturnStatement.java:379)
	at org.eclipse.jdt.internal.compiler.ast.Block.traverse(Block.java:148)
	at org.eclipse.jdt.internal.compiler.ast.IfStatement.traverse(IfStatement.java:293)
	at org.eclipse.jdt.internal.compiler.ast.MethodDeclaration.traverse(MethodDeclaration.java:365)
	at org.eclipse.jdt.internal.compiler.ast.TypeDeclaration.traverse(TypeDeclaration.java:1479)
	at org.eclipse.jdt.internal.compiler.ast.CompilationUnitDeclaration.traverse(CompilationUnitDeclaration.java:826)
	at org.eclipse.jdt.internal.compiler.ast.CompilationUnitDeclaration.traverse(CompilationUnitDeclaration.java:787)
	at spoon.support.compiler.jdt.JDTBasedSpoonCompiler.lambda$buildModel$0(JDTBasedSpoonCompiler.java:437)
	at spoon.support.compiler.jdt.JDTBasedSpoonCompiler.forEachCompilationUnit(JDTBasedSpoonCompiler.java:466)
	at spoon.support.compiler.jdt.JDTBasedSpoonCompiler.buildModel(JDTBasedSpoonCompiler.java:435)
	at spoon.support.compiler.jdt.JDTBasedSpoonCompiler.buildUnitsAndModel(JDTBasedSpoonCompiler.java:372)
	at spoon.support.compiler.jdt.JDTBasedSpoonCompiler.buildSources(JDTBasedSpoonCompiler.java:337)
	at spoon.support.compiler.jdt.JDTBasedSpoonCompiler.build(JDTBasedSpoonCompiler.java:114)
	at spoon.support.compiler.jdt.JDTBasedSpoonCompiler.build(JDTBasedSpoonCompiler.java:97)
	at spoon.Launcher.buildModel(Launcher.java:755)
	at lsifjava.ProjectIndexer.index(ProjectIndexer.java:125)
	at lsifjava.Main.main(Main.java:18)

[monperrus]

Thanks @Strum355, are you trying to fix it?