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Suppose we have a class like this: public class xx { public interface Foo<T> { T getValue(); void setValue(T value); } public void resetFoos(Iterable<Foo<?>> foos) { for (Foo<?> foo : foos) foo.setValue(foo.getValue()); } } It will fail to compile even though intuitively it seems like it "should": xx.java:10: setValue(capture#496 of ?) in xx.Foo<capture#496 of ?> cannot be applied to (java.lang.Object) foo.setValue(foo.getValue()); The reason is that foo does not have a bound generic type, so the compiler doesn't "know" that the output of foo.getValue() is compatible with the input of foo.setValue() . So to fix this you have to create a new method just for the purpose of binding the generic type parameter in the for() loop: public class xx { public interface Foo<T> { T getValue(); void setValue(T value); } public void resetFoos(Iterable<Foo<?>> foos) { for (Foo<?> foo : foos) this.resetFoo(foo); } // stupid extra method here just to bind <T> private <T> void resetFoo(Foo<T> foo) { foo.setValue(foo.getValue()); } } This has always annoyed me. Plus, it seems like there can be a simple solution. My question: Is there any "good" reason why the java language shouldn't be extended to allow generic type declarations on variable declarations? For example: public class xx { public interface Foo<T> { T getValue(); void setValue(T value); } public void resetFoos(Iterable<Foo<?>> foos) { for (Foo<?> foo : foos) { final <T> Foo<T> typedFoo = foo; foo.s

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