Source for file ChoiceValidatorRule.class.php

<?php
 
require_once(HARMONI."utilities/FieldSetValidator/rules/ValidatorRule.interface.php");
 
/**
 * a ChoiceValidatorRule checks a value against a certain given number of choices
 *
 * @package harmoni.utilities.fieldsetvalidator.rules
 * 
 * @copyright Copyright &copy; 2005, Middlebury College
 * @license http://www.gnu.org/copyleft/gpl.html GNU General Public License (GPL)
 *
 * @version $Id: ChoiceValidatorRule.class.php,v 1.7 2007/09/04 20:25:55 adamfranco Exp $
 */ 
class ChoiceValidatorRule 
    extends ValidatorRuleInterface
{
    /**
     * an array of choices to allow
     * 
     * @access private
     * @var array $_choices the array of choices
     */ 
    var $_choices;
    
    /**
     * the concstructor
     * 
     * @param mixed $choice1,$choice2,... a variable-length list of choices to allow
     *  if any of $choiceN are an array, all the values contained within are used
     * @access public
     * @return void 
     ***/
    function ChoiceValidatorRule() {
        $a = func_get_args();
        $choices = array();
        foreach ($a as $c) {
            if (is_array($c)) $choices = array_merge($choices,$c);
            else $choices[] = $c;
        }
        $this->_choices = array_unique($choices);
    }
    
    /**
     * checks a given value against the given choices
     * @param mixed $val the value to check against the rule
     * @access public
     * @return boolean true if the check succeeds, false if it (guess...) fails.
     ***/
    function check( $val ) {
        // go through the choices array and see if $val is in there somewhere
        foreach ($this->_choices as $choice) if ($val == $choice) return true;
        return false;
    }
    
    /**
     * This is a static method to return an already-created instance of a validator
     * rule. There are at most about a hundred unique rule objects in use durring
     * any given execution cycle, but rule objects are instantiated hundreds of
     * thousands of times.
     *
     * This method follows a modified Singleton pattern
     * 
     * @return object ValidatorRule 
     * @access public
     * @static
     * @since 3/28/05
     */
    function getRule () {
        // Because there is no way in PHP to get the class name of the descendent
        // class on which this method is called, this method must be implemented
        // in each descendent class.
        $a = func_get_args();
 
        if (!isset($GLOBALS['validator_rules']) || !is_array($GLOBALS['validator_rules']))
            $GLOBALS['validator_rules'] = array();
        
        $class = __CLASS__;
        if (is_array($a)) {
            ob_start();
            print $class."(";
            print_r($a);
            print ")";
            $ruleKey = ob_get_contents();
            ob_end_clean();
        } else
            $ruleKey = $class."(".implode(", ",$a).")";
 
        if (!isset($GLOBALS['validator_rules'][$ruleKey])) {
            $evalString = '$GLOBALS[\'validator_rules\'][$ruleKey] = new '.$class.'(';
            $i = 0;
            foreach (array_keys($a) as $key) {
                if ($i > 0)
                    $evalString .= ", ";
                $evalString .= '$a['.$key.']';
                $i++;
            }
            $evalString .= ');';
            eval($evalString);
        }
        
        return $GLOBALS['validator_rules'][$ruleKey];
    }
    
    /**
     * Return a key that can be used to identify this Rule for caching purposes.
     * If this rule takes no arguments, the class name should be sufficient.
     * otherwise, append the arguments.
     *
     * This method should only be called by ValidatorRules.
     * 
     * @return string 
     * @access protected
     * @since 3/29/05
     */
    function getRuleKey () {
        return get_class($this)."(".implode(", ",$this->_choices).")";
    }
}
 
?>