code: public boolean checkedOut() throws UnsupportedRepositoryOperationException, RepositoryException
     {
        // this will also check if item is valid
        NodeData vancestor = getVersionableAncestor();
        if (vancestor != null)
        {
           PropertyData isCheckedOut =
              (PropertyData)dataManager.getItemData(vancestor, new QPathEntry(Constants.JCR_ISCHECKEDOUT, 1),
                 ItemType.PROPERTY);
  
           return ValueDataUtil.getBoolean(isCheckedOut.getValues().get(0));
        }
  
        return true;
     }
docs: Tell if this node or its nearest versionable ancestor is checked-out.
  
  @return boolean
  @throws UnsupportedRepositoryOperationException
  if Versionable operations is not supported
  @throws RepositoryException
  if error occurs