Unsupported Java 8 syntax

Question

Unsupported Java 8 syntax

jejung opened this issue 8 years ago · comments

The following code fails with IllegalArgumentException:

public class Main { 

    public static <T> T[] producer(T... ts){
        return ts;
    }

    public static <T> void consumer(Supplier<? extends T> objs){
    }

    public static void main(String[] args) throws IOException {
        consumer(Main::producer);
        new Indexer().index(Main.class.getClassLoader().getResourceAsStream("com/test/Main.class"));
    }
}

The full stack trace is:

Exception in thread "main" java.lang.IllegalArgumentException: Expected character '^' at position 2
at org.jboss.jandex.GenericSignatureParser.expect(GenericSignatureParser.java:262)
at org.jboss.jandex.GenericSignatureParser.parseMethodSignature(GenericSignatureParser.java:298)
at org.jboss.jandex.Indexer.parseMethodSignature(Indexer.java:971)
at org.jboss.jandex.Indexer.applySignatures(Indexer.java:958)
at org.jboss.jandex.Indexer.index(Indexer.java:1449)
at com.test.Main.main(Main.java:29)

Here is a simple test project, hope this helps.

Jason T. Greene · Answer 1 · Thu Aug 25 2016 04:37:45 GMT+0800 (China Standard Time)

Interesting, what java compiler and version are you using?

Jason T. Greene · Answer 2 · Thu Aug 25 2016 05:05:47 GMT+0800 (China Standard Time)

The reason I ask is that your example seems to contain a class file that violates the VM spec. Your not supposed to be able to return a type argument, so it looks like a compiler bug. I'm trying to figure out if I need special handling if its a widespread issue, or if its only a specific compiler version with the problem.

private static ? extends java.lang.Object[] lambda$0();
descriptor: ()[Ljava/lang/Object;
flags: ACC_PRIVATE, ACC_STATIC, ACC_SYNTHETIC
Signature: #64 // ()+[Ljava/lang/Object;
Code:
stack=1, locals=0, args_size=0
0: iconst_0
1: anewarray #3 // class java/lang/Object
4: invokestatic #65 // Method producer:([Ljava/lang/Object;)[Ljava/lang/Object;
7: areturn
LocalVariableTable:
Start Length Slot Name Signature

Jean Jung · Answer 3 · Thu Aug 25 2016 20:05:57 GMT+0800 (China Standard Time)

I was compiling and running from eclipse, I tried to reproduce the problem out of eclipse but without success, so I think the problem may be with the eclipse compiler, can you confirm it?

Eclipse details:

Eclipse Java EE IDE for Web Developers.

Version: Neon Release (4.6.0)
Build id: 20160613-1800

Stanislav Spiridonov · Answer 4 · Mon Oct 18 2021 13:44:29 GMT+0800 (China Standard Time)

Hi, I have the same issue. Also inside the Eclipse

Caused by: java.lang.IllegalArgumentException: Expected character '^' at position 2
	at org.jboss.jandex.GenericSignatureParser.expect(GenericSignatureParser.java:262)
	at org.jboss.jandex.GenericSignatureParser.parseMethodSignature(GenericSignatureParser.java:298)
	at org.jboss.jandex.Indexer.parseMethodSignature(Indexer.java:1424)
	at org.jboss.jandex.Indexer.applySignatures(Indexer.java:1411)
	at org.jboss.jandex.Indexer.index(Indexer.java:1968)
	at io.quarkus.deployment.steps.ApplicationIndexBuildStep$1.visitFile(ApplicationIndexBuildStep.java:38)
	at io.quarkus.deployment.steps.ApplicationIndexBuildStep$1.visitFile(ApplicationIndexBuildStep.java:27)
	at java.base/java.nio.file.Files.walkFileTree(Files.java:2811)
	at java.base/java.nio.file.Files.walkFileTree(Files.java:2882)
	at io.quarkus.deployment.steps.ApplicationIndexBuildStep.build(ApplicationIndexBuildStep.java:27)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:568)
	at io.quarkus.deployment.ExtensionLoader$2.execute(ExtensionLoader.java:820)
	at io.quarkus.builder.BuildContext.run(BuildContext.java:277)
	at org.jboss.threads.ContextHandler$1.runWith(ContextHandler.java:18)
	at org.jboss.threads.EnhancedQueueExecutor$Task.run(EnhancedQueueExecutor.java:2449)
	at org.jboss.threads.EnhancedQueueExecutor$ThreadBody.run(EnhancedQueueExecutor.java:1478)
	at java.base/java.lang.Thread.run(Thread.java:833)
	at org.jboss.threads.JBossThread.run(JBossThread.java:501)

Is there some workaround for it?

Stanislav Spiridonov · Answer 5 · Mon Oct 18 2021 13:45:26 GMT+0800 (China Standard Time)

Signature is ()+Lone/util/streamex/StreamEx<Lme/snowdrop/istio/api/networking/v1beta1/Server;>;

Hélios GILLES · Answer 6 · Tue Feb 14 2023 21:50:24 GMT+0800 (China Standard Time)

Same problem for me.

Ladislav Thon · Answer 7 · Tue Feb 14 2023 22:09:45 GMT+0800 (China Standard Time)

Please provide actionable information. I take bytecode parsing issues very seriously, but I need an actual reproducer. A Java (or Kotlin, or Scala, or Groovy, or whatever) source code is enough, as is a JAR file on Maven Central or similar.

Hélios GILLES · Answer 8 · Wed Feb 15 2023 22:48:08 GMT+0800 (China Standard Time)

First it's in Eclipse, I don't have any problem when compiling the code with javac.
I identified the exact line on my code that produces the "bug". Now I'm trying to make a small sample snippet and I will open a bug in Eclipse JDT.

Ladislav Thon · Answer 9 · Wed Feb 15 2023 22:54:16 GMT+0800 (China Standard Time)

The entire Jandex test suite runs with JDT on each pull request (or it should, at least :-) ). If there's a way to reproduce the problem with a small piece of Java source code, even if javac works just fine, I'd love to add it to the Jandex test suite. Thanks for your work on the reproducer!

Hélios GILLES · Answer 10 · Thu Feb 16 2023 18:00:05 GMT+0800 (China Standard Time)

I did managed to reproduce it with Eclipse JDT, you can see a sample code in eclipse-jdt/eclipse.jdt.core#756

Ladislav Thon · Answer 11 · Thu Feb 16 2023 20:58:22 GMT+0800 (China Standard Time)

Thank you! I managed to simplify your reproducer a little bit more (see the JDT issue) and I can add a test to the Jandex test suite for this.