Catch `NoClassDefFoundError` when loading methods

[freya022]

Those happen if the method returns an unknown type, I also added documentation for the IllegalArgumentException thrown when loading parameter classes

[lukehutch]

Great contribution, thanks. I'll check if FieldInfo and ClassInfo need the same treatment.

[lukehutch]

@freya022 OK, so I handled this a different way, by moving the try...catch in the loadClass method instead -- please check the latest git version and let me know if this resolves the issue you were seeing, without the extra catch phrases that you added.

[freya022]

@freya022 OK, so I handled this a different way, by moving the try...catch in the loadClass method instead -- please check the latest git version and let me know if this resolves the issue you were seeing, without the extra catch phrases that you added.

The extra catch was necessary because the exception is thrown when loading the method, the return type of the method is never loaded by ClassGraph, and so it must be loaded by the VM when getting the method, here's the stack trace I get, with my changes it would have been wrapped in an IllegalArgumentException, but with your changes, it isn't:

Exception in thread "main" java.lang.NoClassDefFoundError: org/springframework/boot/context/event/ApplicationReadyEvent
    at java.base/java.lang.Class.getDeclaredMethods0(Native Method)
    at java.base/java.lang.Class.privateGetDeclaredMethods(Class.java:3578)
    at java.base/java.lang.Class.getMethodsRecursive(Class.java:3719)
    at java.base/java.lang.Class.getMethod0(Class.java:3705)
    at java.base/java.lang.Class.getMethod(Class.java:2393)
    at io.github.classgraph.MethodInfo.loadClassAndGetMethod(MethodInfo.java:668)
    at com.freya02.bot.Main.main(Main.kt:34)
Caused by: java.lang.ClassNotFoundException: org.springframework.boot.context.event.ApplicationReadyEvent
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:641)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:188)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:526)
    ... 7 more

The method loaded is public ApplicationReadyEvent test(), and is in an external library where the dependency for this class is optional

[lukehutch]

Ah, of course, your original change even said that in the comments. Thanks, I'll add the catch back again.

[freya022]

Ah, of course, your original change even said that in the comments. Thanks, I'll add the catch back again.

I don't think adding it for the constructor is necessary, it returns itself, which is already loaded at this point, and the superclasses would be checked by the VM

[lukehutch]

@freya022 Good catch, thanks.

[lukehutch]

Released in 4.8.175. Thank you!