org.corpus_tools.salt.core

Interface GraphTraverseHandler

All Known Implementing Classes:

SCorpusGraphDOTWriter, SDocumentGraphDOTWriter

public interface GraphTraverseHandler

The interface of a callback handler for traversing a Graph object. When invoking the method Graph#traverse(org.eclipse.emf.common.util.EList, GRAPH_TRAVERSE_TYPE, String, GraphTraverseHandler) an object implementing this interface must be passed. This interface contains three methods #checkConstraint(GRAPH_TRAVERSE_TYPE, String, Relation, Node, long), #nodeReached(GRAPH_TRAVERSE_TYPE, String, Node, Relation, Node, long) and #nodeLeft(GRAPH_TRAVERSE_TYPE, String, Node, Relation, Node, long). If the traversal reaches a new Node object being contained in the Graph object, the method #checkConstraint(GRAPH_TRAVERSE_TYPE, String, Relation, Node, long) will be invoked. If this method returns true, it means that this node and eventually its sub-graph will also be traversed. When true is returned, the method #nodeReached(GRAPH_TRAVERSE_TYPE, String, Node, Relation, Node, long) will be invoked, when reaching the node and #nodeLeft(GRAPH_TRAVERSE_TYPE, String, Node, Relation, Node, long) when leaving the node.

Author:

Florian Zipser

Method Summary

Methods

Modifier and Type	Method and Description
boolean	checkConstraint(SGraph.GRAPH_TRAVERSE_TYPE traversalType, String traversalId, SRelation<SNode,SNode> relation, SNode currNode, long order) This method is called during a traversal to check if the current node and eventually its sub-graph shall be traversed or not.
void	nodeLeft(SGraph.GRAPH_TRAVERSE_TYPE traversalType, String traversalId, SNode currNode, SRelation<SNode,SNode> relation, SNode fromNode, long order) This method will be invoked, when a node is left, after the method #checkConstraint(GRAPH_TRAVERSE_TYPE, String, SRelation, SNode, long) has returned true and the method #nodeReached(GRAPH_TRAVERSE_TYPE, String, SNode, SRelation, SNode, long) has been invoked.
void	nodeReached(SGraph.GRAPH_TRAVERSE_TYPE traversalType, String traversalId, SNode currNode, SRelation<SNode,SNode> relation, SNode fromNode, long order) This method will be invoked, when a node is reached, after the method #checkConstraint(GRAPH_TRAVERSE_TYPE, String, SRelation, SNode, long) has returned true and before the method #nodeLeft(GRAPH_TRAVERSE_TYPE, String, SNode, SRelation, SNode, long) is invoked.

Method Detail

nodeReached

void nodeReached(SGraph.GRAPH_TRAVERSE_TYPE traversalType,
               String traversalId,
               SNode currNode,
               SRelation<SNode,SNode> relation,
               SNode fromNode,
               long order)

This method will be invoked, when a node is reached, after the method #checkConstraint(GRAPH_TRAVERSE_TYPE, String, SRelation, SNode, long) has returned true and before the method #nodeLeft(GRAPH_TRAVERSE_TYPE, String, SNode, SRelation, SNode, long) is invoked.

Parameters:

traversalType - the type of current traversal

traversalId - the id of current traversal, given by the invoking object

currNode - the current node

relation - the relation via which the current node was reached

fromNode - the parent node

order - the number of the relation in the parent node

nodeLeft

void nodeLeft(SGraph.GRAPH_TRAVERSE_TYPE traversalType,
            String traversalId,
            SNode currNode,
            SRelation<SNode,SNode> relation,
            SNode fromNode,
            long order)

This method will be invoked, when a node is left, after the method #checkConstraint(GRAPH_TRAVERSE_TYPE, String, SRelation, SNode, long) has returned true and the method #nodeReached(GRAPH_TRAVERSE_TYPE, String, SNode, SRelation, SNode, long) has been invoked.

Parameters:

traversalType - the type of current traversal

traversalId - the id of current traversal, given by the invoking object

currNode - the current node

relation - the relation via which the current node was reached

fromNode - the parent node

order - the number of the relation in the parent node

checkConstraint

boolean checkConstraint(SGraph.GRAPH_TRAVERSE_TYPE traversalType,
                      String traversalId,
                      SRelation<SNode,SNode> relation,
                      SNode currNode,
                      long order)

This method is called during a traversal to check if the current node and eventually its sub-graph shall be traversed or not. If the return value is false, the traversal for the current path, will stop at the current node and the methods #nodeReached(GRAPH_TRAVERSE_TYPE, String, SNode, SRelation, SNode, long) and #nodeLeft(GRAPH_TRAVERSE_TYPE, String, SNode, SRelation, SNode, long) as well will not be invoked. Otherwise the method #nodeReached(GRAPH_TRAVERSE_TYPE, String, SNode, SRelation, SNode, long) will be invoked, when a new node is reached and #nodeLeft(GRAPH_TRAVERSE_TYPE, String, SNode, SRelation, SNode, long) will be invoked, when this node is left.

Parameters:

traversalType - the type of current traversal

traversalId - the id of current traversal, given by the invoking object

relation - the relation via which the current node was reached

currNode - the current node

order - the number of the relation in the parent node