code: private MtasSolrCollectionCacheItem decode(String s) throws IOException {
      byte[] bytes = Base64.base64ToByteArray(s);
      ObjectInputStream objectInputStream;
      objectInputStream = new ObjectInputStream(new ByteArrayInputStream(bytes));
      try {
        Object o = objectInputStream.readObject();
        if (o instanceof MtasSolrCollectionCacheItem) {
          return (MtasSolrCollectionCacheItem) o;
        } else {
          throw new IOException("unexpected " + o.getClass().getSimpleName());
        }
      } catch (ClassNotFoundException e) {
        throw new IOException(e);
      }
    }
docs: Decode.
  
  @param s the s
  @return the mtas solr collection cache item
  @throws IOException Signals that an I/O exception has occurred.