assertTrue(exception instanceof RuntimeException);

        // Should be instance of Exception
        assertTrue(exception instanceof Exception);

        // Should be instance of Throwable
        assertTrue(exception instanceof Throwable);

        // Should not require try-catch (unchecked exception)
        throwUnchecked(); // This compiles without try-catch
    }

    private void throwUnchecked() {

      this.typeVariableImpl = typeVariableImpl;
    }

    @Override
    public @Nullable Object invoke(Object proxy, Method method, @Nullable Object @Nullable [] args)
        throws Throwable {
      String methodName = method.getName();
      Method typeVariableMethod = typeVariableMethods.get(methodName);
      if (typeVariableMethod == null) {
        throw new UnsupportedOperationException(methodName);

      this.typeVariableImpl = typeVariableImpl;
    }

    @Override
    public @Nullable Object invoke(Object proxy, Method method, @Nullable Object @Nullable [] args)
        throws Throwable {
      String methodName = method.getName();
      Method typeVariableMethod = typeVariableMethods.get(methodName);
      if (typeVariableMethod == null) {
        throw new UnsupportedOperationException(methodName);