(reflect) Concrete Type classes could define toString()

The Type instances that you get back from e.g. Method.getGenericReturnType() could define useful toString() methods. At the moment you get the default string, such as "sun.reflect.generics.reflectiveObjects.ParameterizedTypeImpl@1e0be38". Existing reflection classes do define useful toString() methods, e.g. Method.toString() which may return "public abstract java.util.Set T.stringSet()". Having a useful toString() makes it much easier to produce meaningful exception messages in code that uses reflection ("Could not map " + parameterizedType + " to a factory").

Incidentally Method.toString() could then use getGenericReturnType() and getGenericParameterTypes() instead of getReturnType() and getParameterTypes().