How to use org.jivesoftware.smackx.xdata

  private static DataForm createDefaultInitiationForm() {
    DataForm form = new DataForm(DataForm.Type.form);
    FormField field = new FormField(STREAM_DATA_FIELD_NAME);
    field.setType(FormField.Type.list_single);
    if (!IBB_ONLY) {
      field.addOption(new FormField.Option(Bytestream.NAMESPACE));
    }
    field.addOption(new FormField.Option(DataPacketExtension.NAMESPACE));
    form.addField(field);
    return form;
  }
}

/**
 * Create a decorator from an existing {@link Form} for node configuration.
 * Typically, this can be used to create a decorator for an answer form
 * by using the result of {@link #createAnswerForm()} as the input parameter.
 *
 * @param nodeConfigForm
 */
public ConfigureForm(Form nodeConfigForm) {
  super(nodeConfigForm.getDataFormToSend());
}

/**
 * Check if the room supports a members only configuration.
 *
 * @return <code>true</code> if supported, <code>false</code> if not.
 */
public boolean supportsMembersOnly() {
  return answerForm.hasField(MUC_ROOMCONFIG_MEMBERSONLY);
}

private static DataForm getNewMamForm() {
  FormField field = new FormField(FormField.FORM_TYPE);
  field.setType(FormField.Type.hidden);
  field.addValue(MamElements.NAMESPACE);
  DataForm form = new DataForm(DataForm.Type.submit);
  form.addField(field);
  return form;
}

private static FormField getWithFormField(Jid withJid) {
  FormField formField = new FormField(FORM_FIELD_WITH);
  formField.addValue(withJid.toString());
  return formField;
}

  public void deleteUser(Set<EntityBareJid> jidsToDelete)
          throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
    RemoteCommand command = deleteUser();
    command.execute();

    Form answerForm = command.getForm().createAnswerForm();

    FormField accountJids = answerForm.getField("accountjids");
    accountJids.addValues(JidUtil.toStringList(jidsToDelete));

    command.execute(answerForm);
    assert (command.isCompleted());
  }
}

/**
 * Adds the given Date as XEP-0082 formated string by invoking {@link #addValue(CharSequence)} after the date
 * instance was formated.
 *
 * @param date the date instance to add as XEP-0082 formated string.
 * @since 4.3.0
 */
public void addValue(Date date) {
  String dateString = XmppDateTime.formatXEP0082Date(date);
  addValue(dateString);
}

  @Override
  public int compare(FormField f1, FormField f2) {
    return f1.getVariable().compareTo(f2.getVariable());
  }
});

private static void validateThatFieldIsText(FormField field) {
  switch (field.getType()) {
  case text_multi:
  case text_private:
  case text_single:
    break;
  default:
    throw new IllegalArgumentException("This field is not of type text (multi, private or single).");
  }
}

@Override
public XmlStringBuilder toXML(String enclosingNamespace) {
  XmlStringBuilder xml = new XmlStringBuilder(this);
  // Add attribute
  xml.optAttribute("label", getLabel());
  xml.rightAngleBracket();
  // Add element
  xml.element("value", getValue());
  xml.closeElement(this);
  return xml;
}

@Override
public String toString() {
  return getLabel();
}

  @Override
  public void connectionCreated(XMPPConnection connection) {
    getInstanceFor(connection);
  }
});

@Override
public String toString() {
  switch (this) {
  case bool:
    return "boolean";
  default:
    return this.name().replace('_', '-');
  }
}

private static String getSingleValue(FormField formField) {
  List<String> values = formField.getValuesAsString();
  if (values.isEmpty()) {
    return "";
  } else {
    return values.get(0);
  }
}

@Override
public boolean equals(Object obj) {
  if (obj == null)
    return false;
  if (obj == this)
    return true;
  if (!(obj instanceof FormField))
    return false;
  FormField other = (FormField) obj;
  return toXML(null).equals(other.toXML(null));
}

public Builder limitResultsToJid(Jid withJid) {
  if (withJid == null) {
    return this;
  }
  FormField formField = getWithFormField(withJid);
  formFields.put(formField.getVariable(), formField);
  return this;
}

public SubscribeForm(Form subscribeOptionsForm) {
  super(subscribeOptionsForm.getDataFormToSend());
}

/**
 * Check if the room supports password protection.
 *
 * @return <code>true</code> if supported, <code>false</code> if not.
 */
public boolean supportsPasswordProtected() {
  return answerForm.hasField(MUC_ROOMCONFIG_PASSWORDPROTECTEDROOM);
}

/**
 * Sets the form of the current stage. This should be used when setting a
 * response. It could be a form to fill out the information needed to go to
 * the next stage or the result of an execution.
 *
 * @param form the form of the current stage to fill out or the result of the
 *      execution.
 */
protected void setForm(Form form) {
  data.setForm(form.getDataFormToSend());
}

private JoinQueuePacket(EntityBareJid workgroup, Form answerForm, Jid userID) {
  super("join-queue", "http://jabber.org/protocol/workgroup");
  this.userID = userID;
  setTo(workgroup);
  setType(IQ.Type.set);
  form = answerForm.getDataFormToSend();
  addExtension(form);
}