code: @Override
      public synchronized void clear() {
          File[] files = mRootDirectory.listFiles();
          if (files != null) {
              for (File file : files) {
                  file.delete();
              }
          }
          mEntries.clear();
          mTotalSize = 0;
          //todo add queue markers
          //JusLog.d("Cache cleared.");
      }
docs: Clears the cache. Deletes all cached files from disk.