Both two methods handle InvocationTargetException from Endpoint @OnMessage method like this:

        try {
            result = method.invoke(pojo, parameters);
        } catch (IllegalAccessException | InvocationTargetException e) {
            throw new IllegalArgumentException(e);
        }

I'd like to suggest to use

org.apache.tomcat.util.ExceptionUtils#unwrapInvocationTargetException() and RuntimeException

, which is like below:

        try {
            result = method.invoke(pojo, parameters);
        } catch (IllegalAccessException | InvocationTargetException e) {
            Throwable throwable = ExceptionUtils.unwrapInvocationTargetException(e);
            if (throwable instanceof RuntimeException) {
                throw (RuntimeException) throwable;
            } else {
                throw new RuntimeException(throwable);
            }
        }