Bug 417288

Description Sterling Greene 2013-09-15 16:36:51 EDT

Created attachment 235495 [details]
main.java source for the problem (same as github)

I've created a standalone project with just the parts that do not compile for me.  There seems to be some confusion between the two "method" methods, one takes only varargs (Object...) and the other takes a Class and varargs (Class, Object...)

https://github.com/big-guy/generic-method-bug/blob/master/src/main/java/main.java

The error is:
----------
1. ERROR in generic-method-bug/src/main/java/main.java (at line 18)
        list.addAll(method(type, thingThing));
             ^^^^^^
The method addAll(Collection<? extends T>) in the type List<T> is not applicable for the arguments (List<Object>)
----------
1 problem (1 error)

Eclipse suggests changing the return type of method(Class, Object...) to Collection<? extends T>, but that only changes the error's argument type from List<Object> to (List<capture#3-of ? extends Object>).  Ctrl+clicking the method  name on line 18 takes me to the correct method, but the mouseover shows the signature <Object> List<Object> method(Class<Object>, Object...)

I can workaround the issue by using a local variable or casting the first argument to Class.  Casting to Class<T> causes the problem to return.  Oddly enough, if I change the name of method(Object...), the problem also goes away.

I've reproduced this problem with the batch compiler in 3.7.2, 4.3, 4.3.1rc3 and 4.4-m1.   My variations compile with Sun JDK 1.5.0_22 and OpenJDK 1.7.0_25.

The actual class is (flattenToList methods):
https://github.com/gradle/gradle/blob/master/subprojects/base-services/src/main/java/org/gradle/util/CollectionUtils.java

I'm not sure if this is the same issue:
https://bugs.eclipse.org/bugs/show_bug.cgi?id=415734