add Minify::getCache() and Minify_Cache_Abstract that all cache classes must implement

min/lib/Minify.php

@@ -86,6 +86,16 @@ class Minify {
         }
     }
 
+    /**
+     * Get Minify cache
+     *
+     * @return Minify_Cache_Abstract|null
+     */
+    public static function getCache()
+    {
+        return self::$_cache;
+    }
+    
     /**
      * Serve a request for a minified file. 
      * 
@@ -396,7 +406,7 @@ class Minify {
     /**
      * Any Minify_Cache_* object or null (i.e. no server cache is used)
      *
-     * @var Minify_Cache_File
+     * @var Minify_Cache_Abstract
      */
     private static $_cache = null;
     

min/lib/Minify/Cache/APC.php

@@ -14,7 +14,7 @@
  * @package Minify
  * @author Chris Edwards
  **/
-class Minify_Cache_APC {
+class Minify_Cache_APC extends Minify_Cache_Abstract {
 
     /**
      * Create a Minify_Cache_APC object, to be passed to

min/lib/Minify/Cache/Abstract.php

@@ -0,0 +1,63 @@
+<?php
+
+/**
+ * Class Minify_Cache_Abstract
+ *
+ * @package Minify
+ */
+abstract class Minify_Cache_Abstract {
+    /**
+     * Write data to cache.
+     *
+     * @param string $id cache id (e.g. a filename)
+     * @param string $data
+     *
+     * @return bool success
+     */
+    public function store($id, $data)
+    {
+    }
+
+    /**
+     * Get the size of a cache entry
+     *
+     * @param string $id cache id (e.g. a filename)
+     *
+     * @return int size in bytes
+     */
+    public function getSize($id)
+    {
+    }
+
+    /**
+     * Does a valid cache entry exist?
+     *
+     * @param string $id       cache id (e.g. a filename)
+     * @param int    $srcMtime mtime of the original source file(s)
+     *
+     * @return bool exists
+     */
+    public function isValid($id, $srcMtime)
+    {
+    }
+
+    /**
+     * Send the cached content to output
+     *
+     * @param string $id cache id (e.g. a filename)
+     */
+    public function display($id)
+    {
+    }
+
+    /**
+     * Fetch the cached content
+     *
+     * @param string $id cache id (e.g. a filename)
+     *
+     * @return string
+     */
+    public function fetch($id)
+    {
+    }
+}

min/lib/Minify/Cache/File.php

@@ -4,7 +4,7 @@
  * @package Minify
  */
 
-class Minify_Cache_File {
+class Minify_Cache_File extends Minify_Cache_Abstract {
     
     public function __construct($path = '', $fileLocking = false)
     {

min/lib/Minify/Cache/Memcache.php

@@ -17,7 +17,7 @@
  * }
  * </code>
  **/
-class Minify_Cache_Memcache {
+class Minify_Cache_Memcache extends Minify_Cache_Abstract {
     
     /**
      * Create a Minify_Cache_Memcache object, to be passed to 

min/lib/Minify/Cache/WinCache.php

@@ -14,8 +14,7 @@
  * @package Minify
  * @author Matthias Fax
  **/
-class Minify_Cache_WinCache
-{
+class Minify_Cache_WinCache extends Minify_Cache_Abstract {
     
     /**
      * Create a Minify_Cache_Wincache object, to be passed to

min/lib/Minify/Cache/XCache.php

@@ -17,7 +17,7 @@
  * @package Minify
  * @author Elan Ruusamäe <glen@delfi.ee>
  **/
-class Minify_Cache_XCache {
+class Minify_Cache_XCache extends Minify_Cache_Abstract {
 
     /**
      * Create a Minify_Cache_XCache object, to be passed to

min/lib/Minify/Cache/ZendPlatform.php

@@ -17,7 +17,7 @@
  * @package Minify
  * @author Patrick van Dissel
  */
-class Minify_Cache_ZendPlatform {
+class Minify_Cache_ZendPlatform extends Minify_Cache_Abstract {
 
 
     /**