code: public Binder cast(Class<?> returnType, Class<?>... argTypes) {
          return new Binder(this, new Cast(type()), MethodType.methodType(returnType, argTypes));
      }
docs: Cast the incoming arguments to the given MethodType. The casts
  applied are equivalent to those in MethodHandle.explicitCastArguments(MethodType).
  
  @param returnType the target return type
  @param argTypes   the target argument types
  @return a new Binder