Inheriting concrete methods with equal signature due to generics

JastAddJ 7.1.1-284-gc3ca38b Java SE 7

Inheriting two concrete methods with the same signature, due to type argument substitution, should not be allowed.

It is a compile-time error if a class C inherits a concrete method whose signature is a subsignature of another concrete method inherited by C. This can happen if a superclass is generic, and it has two methods that were distinct in the generic declaration, but have the same signature in the particular invocation used.

Test case:

// It is an error if an concrete inherited method has same signature to another concrete inherited method (JLS SE7 8.4.8.4)
// .result=COMPILE_FAIL
class A<U> {
        void m(U u) { }
        void m(Number _) { }
}

class Test extends A<Number> {
}

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