code: public static void isFalse(Boolean expression) {
  		if(!validation) return;
  		notNull(expression);
  		if(expression)
  			throw new ParameterException(ErrorCode.CONSTRAINT);
  	}
docs: Checks if the given boolean expression evaluates to <code>false</code>.
  @param expression The expression to evaluate.
  @throws ParameterException if the given expression does not evaluate to <code>false</code>.