TraversalDescription
and
Traversal
and the new traversal framework's equivalent
Predicate
.public interface ReturnableEvaluator
When a traverser is created the client parameterizes it with an instance of a
ReturnableEvaluator. The traverser then invokes the isReturnableNode()
operation just before returning a specific node, allowing
the client to either approve or disapprove of returning that node.
When implementing a ReturnableEvaluator, the client investigates the
information encapsulated in a TraversalPosition
to decide whether a
node is returnable. For example, here's a snippet detailing a
ReturnableEvaluator that will return all leaf nodes:
ReturnableEvaluator returnEvaluator = new ReturnableEvaluator()
{
public boolean isReturnableNode
( TraversalPosition
position )
{
// Return nodes that don't have any outgoing relationships,
// only incoming relationships, i.e. leaf nodes.
return !position.currentNode
().hasRelationship
(
Direction.OUTGOING
);
}
};
Modifier and Type | Field and Description |
---|---|
static ReturnableEvaluator |
ALL
Deprecated.
A returnable evaluator that returns all nodes encountered.
|
static ReturnableEvaluator |
ALL_BUT_START_NODE
Deprecated.
A returnable evaluator that returns all nodes except the start node.
|
Modifier and Type | Method and Description |
---|---|
boolean |
isReturnableNode(TraversalPosition currentPos)
Deprecated.
Method invoked by traverser to see if the current position is a
returnable node.
|
static final ReturnableEvaluator ALL
static final ReturnableEvaluator ALL_BUT_START_NODE
boolean isReturnableNode(TraversalPosition currentPos)
currentPos
- the traversal positionCopyright © 2002–2014 The Neo4j Graph Database Project. All rights reserved.