Package com.tailf.navu.traversal

Utility package for traversing the NAVU tree (or a subset thereof) using the NAVU API.

See: Description

Interface Summary

Interface	Description
NavuTraversalMean
TraversalFilter

Class Summary

Class	Description
NavuTraversalBfsMean	This implements the NavuTraversalMean for BFS (Breath-first traversal).
NavuTraversalDfsMean	This implements the NavuTraversalMean for DFS (Depth-first traversal).
NavuTreeTraversal	Starting point for both Active and Passive mode traversal

Package com.tailf.navu.traversal Description

Utility package for traversing the NAVU tree (or a subset thereof) using the NAVU API.

Using this package it is possible to retrieve all the NavuNodes that exist in CDB as well as those available through external data providers.

There are two ways that one could use the Traversal API:

• Passive traversal: The user implements the method TraversalFilter.currentNode(com.tailf.navu.NavuNode) and registers it in NavuTreeTraversal.addFilter( com.tailf.navu.traversal.TraversalFilter). When all filters have been registered, the traversal process can be started through NavuTreeTraversal.traverse(). The filters are invoked for each node the traversal process encounters.

• Active traversal: The user retrieves the nodes through an iterator and has full control over when the next NavuNode should be retrieved.

The following example shows a passive traversal (Breadth-first traversal)

  NavuContext ctx = new NavuContext(maapi, th);
  NavuTreeTraversal traversalProcess =
      NavuTreeTraversal.createInstance(ctx, new NavuTraversalBfsMean());
  traversalProcess.addFilter(new TraversalFilter() {
      public void currentNode(NavuNode node) throws NavuException {
          // process the current node
      }
  }
  traversalProcess.traverse();
 

The following example shows a passive traversal (Depth-first traversal)

  NavuContext ctx = new NavuContext(maapi, th);
  NavuTreeTraversal traversalProcess =
      NavuTreeTraversal.createInstance(ctx, new NavuTraversalDfsMean());
  traversalProcess.addFilter(new TraversalFilter() {
      public void currentNode(NavuNode node) throws NavuException {
          // process the current node
      }
  }
  traversalProcess.traverse();
 

The following example shows an active traversal

 
  NavuContext ctx = new NavuContext(maapi, th);
  Iterator<NavuNode> it = NavuTreeTraversal.iterator(ctx);
  while(it.hasNext()) {
      NavuNode currentNode = it.next();
      // Process the node
  }