org.multijava.util.jperf
Class Node

java.lang.Object
  org.multijava.util.jperf.Node

class Node

extends Object

Node is an object class representing nodes in GGPerf's intermediate graph.

Author:

Jiejun KONG

Field Summary
private  Hashtable	adjacency           Adjancency list of the node.
private  long	gValue           g-value of the node.
private  long	label           Label of the node.
private  boolean	visited           Flag indicating whether the node has been visited during the current cyclicity checking process.

 

Constructor Summary

Node(long l)           Creates a new node labelled as the argument in the intermediate graph.

 

Method Summary
void	addAdjacency(Node node, long edge)           Add an adjacent node with its edge to the adjacency list of this node.
void	assignGValue(long val, int max)           Recursively assigns g_value for all nodes that could be reached from this node.
long	getGValue()           Return the G value of the node.
long	getLabel()           Return the label of the node.
boolean	getVisited()           Return the current status of the node.
boolean	reaches(Node target)           Checks wheter there is a path from this node to the target node.
void	setVisited(boolean b)           During a cyclicity checking process, set the status to be the argument.

 

Methods inherited from class java.lang.Object

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

 

Field Detail

label

private final long label

Label of the node.

gValue

private long gValue

g-value of the node.

adjacency

private Hashtable adjacency

Adjancency list of the node. All adjacent nodes with correspondent edges are stored in this list. For any undirected graph, if A<->B, then A appears in B's adjacency list while B is in A's adjacency list.

visited

private boolean visited

Flag indicating whether the node has been visited during the current cyclicity checking process. Since there are indefinite number of passes to check cyclicity of a graph. I can't define a flag for each pass, therefore this flag needs to be cleared before every checking pass to decide reachability.

Node

public Node(long l)

Creates a new node labelled as the argument in the intermediate graph.

Parameters:

l - The label.

getLabel

public long getLabel()

Return the label of the node.

Returns:

The label as a long value.

getGValue

public long getGValue()

Return the G value of the node.

Returns:

The G value as a long value.

addAdjacency

public void addAdjacency(Node node,
                         long edge)

Add an adjacent node with its edge to the adjacency list of this node.

Parameters:

node - The adjacent node.

edge - The edge between this node and the adjacent node.

getVisited

public boolean getVisited()

Return the current status of the node.

Returns:

the status as a boolean value. True means having been visited.

setVisited

public void setVisited(boolean b)

During a cyclicity checking process, set the status to be the argument.

Parameters:

b - the status. True mean having been visited.

reaches

public boolean reaches(Node target)

Checks wheter there is a path from this node to the target node. Uses Depth First Search and marks visited nodes on the path

Parameters:

target - the target node

Returns:

true iff the target node is reachable

assignGValue

public void assignGValue(long val,
                         int max)

Recursively assigns g_value for all nodes that could be reached from this node.

Parameters:

val - the value to assign to this node

max - the maximum value (= # of keywords)