NullPointerException when adding files from an Eclipse plugin

[orichalque]

Hello,

I'm trying to instrument classes from an Eclipse plug-in. I tried first from a simple Maven project and it worked well, but within the Eclipse plug-in environment I get the following stack trace:

Caused by: java.lang.NullPointerException
	at org.eclipse.jdt.internal.compiler.batch.FileSystem.<init>(FileSystem.java:141)
	at org.eclipse.jdt.internal.compiler.batch.Main.getLibraryAccess(Main.java:3086)
	at spoon.support.compiler.jdt.JDTBatchCompiler.getUnits(JDTBatchCompiler.java:107)
	at spoon.support.compiler.jdt.JDTBasedSpoonCompiler.buildUnits(JDTBasedSpoonCompiler.java:410)
	at spoon.support.compiler.jdt.JDTBasedSpoonCompiler.buildUnitsAndModel(JDTBasedSpoonCompiler.java:372)
	at spoon.support.compiler.jdt.JDTBasedSpoonCompiler.buildSources(JDTBasedSpoonCompiler.java:348)
	at spoon.support.compiler.jdt.JDTBasedSpoonCompiler.build(JDTBasedSpoonCompiler.java:119)
	at spoon.support.compiler.jdt.JDTBasedSpoonCompiler.build(JDTBasedSpoonCompiler.java:102)
	at spoon.Launcher.buildModel(Launcher.java:700)
	at spoon.Launcher.run(Launcher.java:651)
	at cl2t.instrumentation.instrumenters.SpoonInstrumenter.instrumentTarget(SpoonInstrumenter.java:51)
	at cl2t.Cl2tRunner.lambda$1(Cl2tRunner.java:69)
	at java.util.ArrayList.forEach(ArrayList.java:1249)
	at cl2t.Cl2tRunner.run(Cl2tRunner.java:69)
	at cl2t.handlers.DiscoveryHandler.execute(DiscoveryHandler.java:35)
	at cl2t.handlers.StatementHandler.execute(StatementHandler.java:22)
	at org.eclipse.ui.internal.handlers.HandlerProxy.execute(HandlerProxy.java:295)
	at org.eclipse.ui.internal.handlers.E4HandlerProxy.execute(E4HandlerProxy.java:90)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.eclipse.e4.core.internal.di.MethodRequestor.execute(MethodRequestor.java:55)
	... 37 more

What I'm doing is this:

                launcher = new Launcher();
		launcher.setArgs(new String[]{"--output-type", "nooutput"})
		String classFile = InstrumentationUtils.getSrcFile(target);
		File file = new File(classFile);
		System.out.println(file.exists()); //true
		FileSystemFile fsf = new FileSystemFile(file);
		launcher.addInputResource(fsf);
		launcher.addProcessor(new CompileProcessor());
		launcher.run();

When running on debug, I saw that the error comes from the following line in the FileSystem class:

protected FileSystem(Classpath[] paths, String[] initialFileNames, boolean annotationsFromClasspath) {
	final int length = paths.length; //paths = null
        ...

Should I add other command line options or is this the same bug as the 2 other issues #1191 and #1116 ?

Best Regards,

Thibault

[surli]

Hi,

is this the same bug as the 2 other issues #1191 and #1116

it really looks like the same bug: did you check by using the last SNAPSHOT version of Spoon?

[orichalque]

Hi,
I noticed that I was using the snapshot 1 of Spoon 5.6.0. I tried with the last one, 77, and I can confirm that it works well now.

Thank you very much