Description Markus Keller 2004-08-26 13:35:51 EDT

I200408241200

public class Main {
	public static void main(String[] args) {
		new C<Double,Integer>().foo(new Integer(1)); //1
		new C<Double,Integer>().foo(new Double(2));  //2
		new C<Number,Number>().foo(new Integer(3));  //3
	}
}

class B <Tb> {
	void foo(Tb b) {
		System.out.println("B: "+b);
	} 
}

class C <Tb, Tc> extends B<Tb> {
	void foo(Tc c) {
		System.out.println("C: "+c);
	}
}

Running Main produces C: 1, C: 2.0, C: 3.
Hovering over foo(..) at //2 shows "void inherit.B<Tb>.foo(Tb b)".
The ASTView says that the method binding at line //2 is "B<Double>.foo(Double)".
Is this OK since the (erased) C#foo(..) overrides B#foo(..) at run time, but not
at compile time? I'm not really sure here - this would be very C++ish ;-(

However, I think //3 should raise an "ambiguous method invocation" error, since
none of the foo(..) methods is "most specific" in this case.


BTW: Sun's javac 1.5.0-beta3-b62 says:

reference to foo is ambiguous, both method foo(Tb) in
inherit.B<java.lang.Number> and method foo(Tc) in
inherit.C<java.lang.Number,java.lang.Number> match
		new C<Number,Number>().foo(new Integer(3));  //3
                ^

... and after removing the offending third call to foo:

name clash: foo(Tc) in inherit.C<Tb,Tc> and foo(Tb) in inherit.B<Tb> have the
same erasure, yet neither overrides the other
class C <Tb, Tc> extends B<Tb> {
^