code: private void guessExceptions(){
  		List<Class<?>> tmpExceptionList = new ArrayList<>();
  		for (Class<?> c:supportedInterfaces){
  			Method[] methods = c.getDeclaredMethods();
  			for (Method m:methods){
  				for (Class<?> exc : m.getExceptionTypes()){
  					if (!tmpExceptionList.contains(exc))
  						tmpExceptionList.add(exc);
  				}
  			}
  		}
  		declaredExceptions = new Class[tmpExceptionList.size()];
  		tmpExceptionList.toArray(declaredExceptions);
  	}
docs: Looks up all possible exceptions.