code: public boolean deleteNode(String nodeId) throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
          boolean res = true;
          try {
              sendPubsubPacket(Type.set, new NodeExtension(PubSubElementType.DELETE, nodeId), PubSubElementType.DELETE.getNamespace());
          } catch (XMPPErrorException e) {
              if (e.getStanzaError().getCondition() == StanzaError.Condition.item_not_found) {
                  res = false;
              } else {
                  throw e;
              }
          }
          nodeMap.remove(nodeId);
          return res;
      }
docs: Delete the specified node.
  
  @param nodeId
  @throws XMPPErrorException
  @throws NoResponseException
  @throws NotConnectedException
  @throws InterruptedException
  @return <code>true</code> if this node existed and was deleted and <code>false</code> if this node did not exist.