org.geotools.graph.traverse

Interface GraphTraversal

All Known Implementing Classes:

BasicGraphTraversal, StagedGraphTraversal

public interface GraphTraversal

Iterates a GraphWalker over the components of a Graph. The order in which components are iterated over is determined by the GraphIterator class. The GraphTraversal is the mediator between the GraphWalker and the GraphIterator.

Upon each visitation, the GraphWalker communicates to the GraphTraversal through a series of return codes, each specifying a different action to perform at that point of the travesal. The following summarizes the meaning of the codes.

Code	Action Taken
CONTINUE	The traversal continues as normal.
SUSPEND	Suspends the traversal at some intermediate stage. This code should be returned if the traversal is intended to be resumed.
KILL_BRANCH	Kills the current branch of the traversal. Depending on the iteration algorithm, returning this code may end the traversal.
STOP	Stops the traversal.

GraphTraversals are started with a call to traverse(). If the traversal is suspended at some intermediate point, an additional call to traverse() will resume the traversal.

Author:

Justin Deoliveira, Refractions Research Inc, jdeolive@refractions.net

See Also:

GraphWalker, GraphIterator, Graph

Field Summary

Fields

Modifier and Type	Field and Description
static int	CONTINUE Signals the traversal to continue
static int	KILL_BRANCH Signals the traversal to kill the current branch
static int	STOP Signals the traversal to stop
static int	SUSPEND Signals the traversal to suspend at some intermediate point

Method Summary

Methods

Modifier and Type	Method and Description
Graph	getGraph() Returns the graph being traversed.
GraphIterator	getIterator() Returns the iterator that specifies the order in which to visit graph components.
GraphWalker	getWalker() Returns the walker (visitor) traversing the graph of the graph.
void	init() Initializes the traversal.
boolean	isVisited(Graphable g)
void	setGraph(Graph graph) Sets the graph being traversed.
void	setIterator(GraphIterator iterator) Sets the iterator that specifies the order in which visit graph components.
void	setVisited(Graphable g, boolean visited)
void	setWalker(GraphWalker walker) Sets the walker (visitor) traversing the graph.
void	traverse() Starts or resumes a traversal over the components of a graph.

Field Detail

CONTINUE

static final int CONTINUE

Signals the traversal to continue

See Also:

Constant Field Values

SUSPEND

static final int SUSPEND

Signals the traversal to suspend at some intermediate point

See Also:

Constant Field Values

KILL_BRANCH

static final int KILL_BRANCH

Signals the traversal to kill the current branch

See Also:

Constant Field Values

STOP

static final int STOP

Signals the traversal to stop

See Also:

Constant Field Values

Method Detail

setGraph

void setGraph(Graph graph)

Sets the graph being traversed.

Parameters:

graph - The graph whose components are being traversed.

getGraph

Graph getGraph()

Returns the graph being traversed.

Returns:

The graph whose components are being traversed.

See Also:

Graph

setIterator

void setIterator(GraphIterator iterator)

Sets the iterator that specifies the order in which visit graph components.

Parameters:

iterator - The iterator over the graph components.

getIterator

GraphIterator getIterator()

Returns the iterator that specifies the order in which to visit graph components.

Returns:

The iterator over the graph components.

See Also:

GraphIterator

setWalker

void setWalker(GraphWalker walker)

Sets the walker (visitor) traversing the graph.

Parameters:

walker - The walker being iterated over the components of the graph.

getWalker

GraphWalker getWalker()

Returns the walker (visitor) traversing the graph of the graph.

Returns:

The walker being iterated over the components.

init

void init()

Initializes the traversal.

traverse

void traverse()

Starts or resumes a traversal over the components of a graph.

isVisited

boolean isVisited(Graphable g)

setVisited

void setVisited(Graphable g,
              boolean visited)