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<?php
/**
* @version      $Id: callback.php 10707 2008-08-21 09:52:47Z eddieajau $
* @package      Joomla.Framework
* @subpackage   Cache
* @copyright    Copyright (C) 2005 - 2008 Open Source Matters. All rights reserved.
* @license      GNU/GPL, see LICENSE.php
* Joomla! is free software. This version may have been modified pursuant
* to the GNU General Public License, and as distributed it includes or
* is derivative of works licensed under the GNU General Public License or
* other free or open source software licenses.
* See COPYRIGHT.php for copyright notices and details.
*/
 
// Check to ensure this file is within the rest of the framework
defined('JPATH_BASE') or die();
 
/**
 * Joomla! Cache callback type object
 *
 * @package     Joomla.Framework
 * @subpackage  Cache
 * @since       1.5
 */
class JCacheCallback extends JCache
{
    /**
     * Executes a cacheable callback if not found in cache else returns cached output and result
     *
     * Since arguments to this function are read with func_get_args you can pass any number of arguments to this method
     * as long as the first argument passed is the callback definition.
     *
     * The callback definition can be in several forms:
     *  - Standard PHP Callback array <http://php.net/callback> [recommended]
     *  - Function name as a string eg. 'foo' for function foo()
     *  - Static method name as a string eg. 'MyClass::myMethod' for method myMethod() of class MyClass
     *
     * @access  public
     * @return  mixed   Result of the callback
     * @since   1.5
     */
    function call()
    {
        // Get callback and arguments
        $args       = func_get_args();
        $callback   = array_shift($args);
 
        return $this->get( $callback, $args );
    }
 
    /**
     * Executes a cacheable callback if not found in cache else returns cached output and result
     *
     * @access  public
     * @param   mixed   Callback or string shorthand for a callback
     * @param   array   Callback arguments
     * @return  mixed   Result of the callback
     * @since   1.5
     */
    function get( $callback, $args, $id=false )
    {
        // Normalize callback
        if (is_array( $callback )) {
            // We have a standard php callback array -- do nothing
        } elseif (strstr( $callback, '::' )) {
            // This is shorthand for a static method callback classname::methodname
            list( $class, $method ) = explode( '::', $callback );
            $callback = array( trim($class), trim($method) );
        } elseif (strstr( $callback, '->' )) {
            /*
             * This is a really not so smart way of doing this... we provide this for backward compatability but this
             * WILL!!! disappear in a future version.  If you are using this syntax change your code to use the standard
             * PHP callback array syntax: <http://php.net/callback>
             *
             * We have to use some silly global notation to pull it off and this is very unreliable
             */
            list( $object_123456789, $method ) = explode('->', $callback);
            global $$object_123456789;
            $callback = array( $$object_123456789, $method );
        } else {
            // We have just a standard function -- do nothing
        }
 
        if (!$id) {
            // Generate an ID
            $id = $this->_makeId($callback, $args);
        }
 
        // Get the storage handler and get callback cache data by id and group
        $data = parent::get($id);
        if ($data !== false) {
            $cached = unserialize( $data );
            $output = $cached['output'];
            $result = $cached['result'];
        } else {
            ob_start();
            ob_implicit_flush( false );
 
            $result = call_user_func_array($callback, $args);
            $output = ob_get_contents();
 
            ob_end_clean();
 
            $cached = array();
            $cached['output'] = $output;
            $cached['result'] = $result;
            // Store the cache data
            $this->store(serialize($cached), $id);
        }
 
        echo $output;
        return $result;
    }
 
    /**
     * Generate a callback cache id
     *
     * @access  private
     * @param   callback    $callback   Callback to cache
     * @param   array       $args   Arguments to the callback method to cache
     * @return  string  MD5 Hash : function cache id
     * @since   1.5
     */
    function _makeId($callback, $args)
    {
        if(is_array($callback) && is_object($callback[0])) {
            $vars = get_object_vars($callback[0]);
            $vars[] = strtolower(get_class($callback[0]));
            $callback[0] = $vars;
        }
        return md5(serialize(array($callback, $args)));
    }
} "
 
 
output.php:
 
"<?php
/**
* @version      $Id: output.php 10707 2008-08-21 09:52:47Z eddieajau $
* @package      Joomla.Framework
* @subpackage   Cache
* @copyright    Copyright (C) 2005 - 2008 Open Source Matters. All rights reserved.
* @license      GNU/GPL, see LICENSE.php
* Joomla! is free software. This version may have been modified pursuant
* to the GNU General Public License, and as distributed it includes or
* is derivative of works licensed under the GNU General Public License or
* other free or open source software licenses.
* See COPYRIGHT.php for copyright notices and details.
*/
 
// Check to ensure this file is within the rest of the framework
defined('JPATH_BASE') or die();
 
/**
 * Joomla! Cache output type object
 *
 * @package     Joomla.Framework
 * @subpackage  Cache
 * @since       1.5
 */
class JCacheOutput extends JCache
{
    /**
     * Start the cache
     *
     * @access  public
     * @param   string  $id     The cache data id
     * @param   string  $group  The cache data group
     * @return  boolean True if the cache is hit (false else)
     * @since   1.5
     */
    function start( $id, $group=null)
    {
        // If we have data in cache use that...
        $data = $this->get($id, $group);
        if ($data !== false) {
            echo $data;
            return true;
        } else {
            // Nothing in cache... lets start the output buffer and start collecting data for next time.
            ob_start();
            ob_implicit_flush( false );
            // Set id and group placeholders
            $this->_id      = $id;
            $this->_group   = $group;
            return false;
        }
    }
 
    /**
     * Stop the cache buffer and store the cached data
     *
     * @access  public
     * @return  boolean True if cache stored
     * @since   1.5
     */
    function end()
    {
        // Get data from output buffer and echo it
        $data = ob_get_contents();
        ob_end_clean();
        echo $data;
 
        // Get id and group and reset them placeholders
        $id     = $this->_id;
        $group  = $this->_group;
        $this->_id      = null;
        $this->_group   = null;
 
        // Get the storage handler and store the cached data
        $this->store($data, $id, $group);
    }
}