Java 8 Bug

Alan alan at
Fri Nov 8 07:58:31 PST 2013

Sorry if this isn't the correct list ! If not, please tell me where I 
should post this bug.

The following code works in jdk1.7.0_21 but not in jdk1.8.0

private static <E extends Enum<?>> Map<String, Enum<?>> 
parseEnumConstants(Class<E> clazz) {} = ...

Class<?> type = ...


Map<String, Enum<?>> universe = (Map<String, Enum<?>>) 
   required: Class<E>
   found: Class<CAP#1>
   reason: cannot infer type-variable(s) E,U
     (argument mismatch; Class<CAP#2> cannot be converted to Class<CAP#3>)
   where E,U are type-variables:
     E extends Enum<?> declared in method <E>parseEnumConstants(Class<E>)
     U extends Object declared in method <U>asSubclass(Class<U>)
   where CAP#1,CAP#2,CAP#3 are fresh type-variables:
     CAP#1 extends Enum from capture of ? extends Enum
     CAP#2 extends Enum from capture of ? extends Enum
     CAP#3 extends Enum from capture of ? extends Enum

What is really unusual is that I can't see how this error can be 
occuring - none of the method signatures have changed!

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