Add remove method to cache interface

Author: iherwig

src/wcmf/lib/io/Cache.php

@@ -53,6 +53,13 @@ public function get($section, $key);
    */
   public function put($section, $key, $value, $lifetime=null);
 
+  /**
+   * Remove the specified cache entry.
+   * @param $section The cache section
+   * @param $key The key
+   */
+  public function remove($section, $key);
+
   /**
    * Clear the given cache section. The wildcard char '*'
    * may be added to the section name in order to

src/wcmf/lib/io/impl/FileCache.php

@@ -90,6 +90,14 @@ public function put($section, $key, $value, $lifetime=null) {
     $cache->save($item);
   }
 
+  /**
+   * @see Cache::remove()
+   */
+  public function remove($section, $key) {
+    $cache = $this->getCache($section);
+    $cache->deleteItem($this->sanitizeKey($key));
+  }
+
   /**
    * @see Cache::clear()
    */

src/wcmf/lib/model/mapper/SelectStatement.php

@@ -55,6 +55,7 @@ public static function get(RDBMapper $mapper, $id=self::NO_CACHE) {
     else {
       $selectStmt = $cache->get($cacheSection, $cacheId);
       if (!$selectStmt) {
+        $cache->remove($cacheSection, $cacheId);
         $selectStmt = new SelectStatement($mapper, $id);
       }
       $selectStmt->adapter = $mapper->getAdapter();