Package io.milton.resource

Interface DeletableCollectionResource

  • All Superinterfaces:
    CollectionResource, DeletableResource, Resource
    public interface DeletableCollectionResource
extends DeletableResource, CollectionResource
    An extension to DeletableResource and CollectionResource, this interface adds a method to support efficient detection of child locks.

    This interface ONLY needs to be implemented by those who need to improve performance of deleting collections

    In the case of deleting a collection resource it might be inefficient to check for locks by recursively walking through the collection. By implementing this interface you have the ability to use a more efficient approach See HandlerHelper.isLockedOut for an example of checking for locks: 

     
     public boolean isLockedOut( Request inRequest, Resource inResource ) {
       if( inResource == null || !( inResource instanceof LockableResource ) ) {
           return false;
       }
       LockableResource lr = (LockableResource) inResource;
       LockToken token = lr.getCurrentLock();
       if( token != null ) {
           Auth auth = inRequest.getAuthorization();
           String lockedByUser = token.info.lockedByUser;
           if( lockedByUser == null ) {
               log.warn( "Resource is locked with a null user. Ignoring the lock" );
               return false;
           } else if( !lockedByUser.equals( auth.getUser() ) ) {
               log.info( "fail: lock owned by: " + lockedByUser + " not by " + auth.getUser() );
               String value = inRequest.getIfHeader();
               if( value != null ) {
                   if( value.contains( "opaquelocktoken:" + token.tokenId + ">" ) ) {
                       log.info( "Contained valid token. so is unlocked" );
                       return false;
                   }
               }
               return true;
           }
       }
       return false;
   }

    • Method Detail

      • isLockedOutRecursive

        boolean isLockedOutRecursive​(Request request)
        Check to see if this resource or any child resource are locked by someone other then the current user (as per the Authorisation property of the request)
        Parameters:
        request -
        Returns:
        - true indicates that the DELETE request must not proceed because this resource or at least one child resource is locked by someone other then the current user