org.geotools.graph.traverse
Interface GraphTraversal

All Known Implementing Classes:

BasicGraphTraversal

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

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

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

public static final int CONTINUE

Signals the traversal to continue

See Also:

Constant Field Values

SUSPEND

public static final int SUSPEND

Signals the traversal to suspend at some intermediate point

See Also:

Constant Field Values

KILL_BRANCH

public static final int KILL_BRANCH

Signals the traversal to kill the current branch

See Also:

Constant Field Values

STOP

public static final int STOP

Signals the traversal to stop

See Also:

Constant Field Values

Method Detail

setGraph

public void setGraph(Graph graph)

Sets the graph being traversed.

Parameters:

graph - The graph whose components are being traversed.

getGraph

public Graph getGraph()

Returns the graph being traversed.

Returns:

The graph whose components are being traversed.

See Also:

Graph

setIterator

public 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

public 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

public void setWalker(GraphWalker walker)

Sets the walker (visitor) traversing the graph.

Parameters:

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

getWalker

public GraphWalker getWalker()

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

Returns:

The walker being iterated over the components.

init

public void init()

Initializes the traversal.

traverse

public void traverse()

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

isVisited

public boolean isVisited(Graphable g)

setVisited

public void setVisited(Graphable g,
                       boolean visited)