Monat: Dezember 2008

Kommentare gesperrt, weil dieses Posting Spambots magisch anzieht.

Mir ist aufgefallen, daß meine Klasse nicht abfängt wenn man zweimal dasselbe Objekt ins Set setzt. Deshalb ein kleines Update

Nils Langner von PHP hates me hat eine Aufgabe gestellt. Und hier meine spontane Lösung, vom Hirn ins Terminal 🙂

<?php
<div class="moz-text-plain" style="font-family: -moz-fixed; font-size: 13px;" lang="x-western">
<pre>class Foobar {
}

/**
 * @author Matthias Coy
 */
class Set {
    private $set = null;
    private $typ = null;
    private $className = null;

    /**
     * The method to add something to the set. The type of the set is defined by its first entry.
     * @param <type> $something
     * @public
     */
    function push($something) {
        if ($this->set == null) {
            $this->typ = gettype($something);
            $this->set = array();
            array_push($this->set, $something);
            if($this->typ == "object") {
                $class = new ReflectionClass($something);
                $this->className = $class->getName();
                echo "It's a class, with the name: '".$this->className."'\n";
            } else {
                echo "It's something else: '". $this->typ ."'";
            }
        } else {
            $myType = gettype($something);
            if($myType != $this->typ) {
                throw new Exception("Wrong Type, this set is a set of '".$this->typ."'");
            } else {
                if ($myType == "object") {
                    $class = new ReflectionClass($something);
                    if ($this->className != $class->getName()) {
                        throw new Exception("Right Type, but wrong class (is: '".$class->getName()."', should be: '".$this->className."')");
                    }
                    foreach($this->set as $entry) {
                        if ($something === $entry) {
                            throw new Exception('Right Type, but already in Set');
                        }
                    }
                }
                array_push($this->set, $something);
                echo "adding sth. (".$myType.")\n";
            }
        }
    }

    /**
     * Return the last inserted entry of the set.
     *
     * @return <type>
     * @public
     * @throws Exception if set is empty
     */
    function pop() {
        $returnValue = array_pop($this->set);
        if ($returnValue == null) {
            $this->set = null;
            $this->typ = null;
            $this->className = null;
            throw new Exception("Set is not yet defined, please add something first");
        }
        return $returnValue;
    }

    /**
     * Returns the amount of entries in the set
     *
     * @return <type> Entry of the set
     * @public
     */
    function count() {
        return count($this->set);
    }
}

$var1 = new Set();
$var2 = new Foobar();

$mySet = new Set();
$mySet->push($var1);
try {
    // Add something that is different to the types already in the set
    $mySet->push($var2); // throws execption
} catch (Exception $e) {
    print $e->getMessage()."\n";
}
try {
    // Add something which has the right type, but is already inside the set
    $mySet->push($var1); // throws execption
} catch (Exception $e) {
    print $e->getMessage()."\n";
}
while($mySet->count() > 0) {
    $mySet->pop();
}
$mySet->push($var2);
try {
    $mySet->push($var1);
} catch (Exception $e) {
    print $e->getMessage()."\n";
}
/* Output:
It's a class, with the name: 'Set'
Right Type, but wrong class (is: 'Foobar', should be: 'Set')
Right Type, but already in Set
It's a class, with the name: 'Foobar'
Right Type, but wrong class (is: 'Set', should be: 'Foobar')
 */