net.walend.measured
Class AbstractShortestCEDistances

java.lang.Object
  |
  +--net.walend.measured.AbstractShortestCEDistances

All Implemented Interfaces:

HasState, java.io.Serializable, ShortestCEDistances

Direct Known Subclasses:

DijkstraShortestCEDistances, FloydWarshallShortestCEDistances

public abstract class AbstractShortestCEDistances

extends java.lang.Object

implements ShortestCEDistances, java.io.Serializable

AbstractShortestCEDistances contains a 2D array of distances between nodes in a directed graph. This class holds a lot of common workhorse methods used by other classes.

Author:

David Walend dfw1@cornell.edu

See Also:

Serialized Form

Field Summary

private IndexedCEDigraph	base
private int[][]	distances
private CEPathMeter	pathMeter

Constructor Summary

protected

AbstractShortestCEDistances(IndexedCEDigraph ceDigraph, CEPathMeter pathMeter)

Method Summary

protected void	bfTest()
IndexedCEDigraph	getBase()
int	getLength(int from, int to)
int	getLength(java.lang.Object fromNode, java.lang.Object toNode)
CEPathMeter	getPathMeter() Return the path meter used to evaluate these shortest paths.
java.lang.Class	getPrincipleInterface() Returns the class's principle interface for state comparisons.
protected void	initializeDistances()
abstract void	recalculate() Rediscover the shortest paths.
protected void	relax(int fromIndex, int throughIndex, int toIndex)
protected int	safeLength(int from, int to)
boolean	sameStateAs(HasState victim) If two HasStates have the same internal state, return true.
java.lang.String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

distances

private int[][] distances

pathMeter

private CEPathMeter pathMeter

base

private IndexedCEDigraph base

Constructor Detail

AbstractShortestCEDistances

protected AbstractShortestCEDistances(IndexedCEDigraph ceDigraph,
                                      CEPathMeter pathMeter)
                               throws CENegativeWeightCycleException

Method Detail

bfTest

protected void bfTest()
               throws CENegativeWeightCycleException

CENegativeWeightCycleException

getBase

public IndexedCEDigraph getBase()

Specified by:

getBase in interface ShortestCEDistances

initializeDistances

protected void initializeDistances()

relax

protected void relax(int fromIndex,
                     int throughIndex,
                     int toIndex)

recalculate

public abstract void recalculate()
                          throws CENegativeWeightCycleException

Rediscover the shortest paths.

Specified by:

recalculate in interface ShortestCEDistances

CENegativeWeightCycleException

getPathMeter

public CEPathMeter getPathMeter()

Return the path meter used to evaluate these shortest paths.

Specified by:

getPathMeter in interface ShortestCEDistances

getLength

public int getLength(int from,
                     int to)

Specified by:

getLength in interface ShortestCEDistances

safeLength

protected final int safeLength(int from,
                               int to)

getLength

public int getLength(java.lang.Object fromNode,
                     java.lang.Object toNode)
              throws NodeMissingException

Specified by:

getLength in interface ShortestCEDistances

NodeMissingException

getPrincipleInterface

public java.lang.Class getPrincipleInterface()

Description copied from interface: HasState

Returns the class's principle interface for state comparisons. If two objects have different principle interfaces, they never have the same state.

Specified by:

getPrincipleInterface in interface HasState

sameStateAs

public boolean sameStateAs(HasState victim)

Description copied from interface: HasState

If two HasStates have the same internal state, return true.

For objects with subobjects, Generally this method should only return true if the internal objects are equal. Implement a contentsHaveSameState() method to determine if the contents have the same state.

Specified by:

sameStateAs in interface HasState

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object