code: public static Double validateNumber(final String context,
  			final String input, final long minValue, final long maxValue,
  			final boolean allowNull) throws ValidationException {
  		return validator.getValidNumber(context, input, minValue, maxValue,
  				allowNull);
  	}
docs: Number Validation
  
  @param context
  @param input
  @param minValue
  @param maxValue
  @param allowNull
  @return