private Map<String, byte[]> getSerializedAttributes() {
    // Iterate the values and serialize them if necessary before sending them to the server. This
    // makes the application classes unnecessary on the server.
    Map<String, byte[]> serializedAttributes = new ConcurrentHashMap<>();
    for (Map.Entry<String, Object> entry : getAttributes().entrySet()) {
      Object value = entry.getValue();
      byte[] serializedValue = value instanceof byte[] ? (byte[]) value : serialize(value);
      serializedAttributes.put(entry.getKey(), serializedValue);
    }
    return serializedAttributes;
  }
Return the <code>HttpSession</code> for which this object is the facade.
extensions/geode-modules/src/main/java/org/apache/geode/modules/session/catalina/DeltaSession.java