Package search

Class Frontiers.PriorityQueue<Node>

java.lang.Object

search.Frontiers.DebuggingFrontier<Node>

search.Frontiers.PriorityQueue<Node>

All Implemented Interfaces:

FrontierStructure<Node>

Direct Known Subclasses:

Frontiers.StateKeyedPriorityQueue

Enclosing class:

Frontiers

public static class Frontiers.PriorityQueue<Node>
extends Frontiers.DebuggingFrontier<Node>

A frontier as a priority queue, for e.g. A*.

Constructor Summary

Constructors

Constructor	Description
PriorityQueue(Comparator<Node> prioritizer)

Method Summary

Modifier and Type	Method	Description
void	add(Node n)	Adds a (usually newly-generated) tree node to the frontier.
int	countOpen()	Returns the number of open nodes sitting unexpanded in the frontier.
void	debugDisplayFrontier()	Print debugging information about the frontier.
boolean	isEmpty()	Checks whether any tree nodes remain in the frontier
Node	pop()	Removes one tree node from the frontier, and returns it.

Methods inherited from class java.lang.Object

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

Constructor Details

PriorityQueue

public PriorityQueue(Comparator<Node> prioritizer)

Method Details

add

public void add(Node n)

Description copied from interface: FrontierStructure

Adds a (usually newly-generated) tree node to the frontier.

Parameters:

n - The new node

isEmpty

public boolean isEmpty()

Description copied from interface: FrontierStructure

Checks whether any tree nodes remain in the frontier

Returns:

false when the frontier is empty, which generally indicates that the search has failed.

pop

public Node pop()

Description copied from interface: FrontierStructure

Removes one tree node from the frontier, and returns it.

Returns:

The dequeued tree node

countOpen

public int countOpen()

Description copied from interface: FrontierStructure

Returns the number of open nodes sitting unexpanded in the frontier.

Returns:

The number of open nodes

debugDisplayFrontier

public void debugDisplayFrontier()

Description copied from interface: FrontierStructure

Print debugging information about the frontier. By default, does nothing.

Specified by:

debugDisplayFrontier in interface FrontierStructure<Node>

Overrides:

debugDisplayFrontier in class Frontiers.DebuggingFrontier<Node>