Package search

Class AStarSearcher<State,Node extends SearchTreeNode<Node,State> & KnowsOwnCost>

java.lang.Object

search.GraphSearcher<State,Node,Frontier>

search.PriorityQueueSearcher<State,Node,Frontier>

search.AStarFrontierSearcher<State,Node,Frontiers.PriorityQueue<Node>>

search.AStarSearcher<State,Node>

Type Parameters:

State - Type representing elements of the search space.

Node - Type representing nodes in the search tree. Each node typically contains a reference to a State element.

Direct Known Subclasses:

AStarSearcher.PathNodes, AStarSearcher.SimpleNodes, MovesFinder

public class AStarSearcher<State,Node extends SearchTreeNode<Node,State> & KnowsOwnCost>
extends AStarFrontierSearcher<State,Node,Frontiers.PriorityQueue<Node>>

Extension of AStarFrontierSearcher to fix the frontier structure with a minimal priority queue implementation.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	AStarSearcher.PathNodes<State>	A specialization of AStarSearcher to use a minimal implementation of hierarchical search tree nodes (with a state, accumulated cost, and pointer to a parent tree node), with the frontier implementation still exposed as a type parameter.
static class	AStarSearcher.SimpleNodes<State>	A specialization of AStarSearcher to use a minimal implementation of unrelated search tree nodes (with a state and accumulated cost only), with the frontier implementation still exposed as a type parameter.

Constructor Summary

Constructors

Constructor	Description
AStarSearcher(Predicate<Node> goalTest, Function<Node,Double> heuristic, Function<Frontiers.PriorityQueue<Node>,ExploredSet<Node>> exploredSetFactory, Function<State,Node> initializer)	Primary constructor for this class; other constructor relay to this one.
AStarSearcher(Predicate<Node> goalTest, Function<Node,Double> heuristic, Function<State,Node> initializer)	Constructor for this class which does not maintain an explored set.

Method Summary

Methods inherited from class search.AStarFrontierSearcher

debugFrontierAddition, debugFrontierRemoval

Methods inherited from class search.GraphSearcher

debugExpansion, debugFrontier, debugFrontierExhausted, debugFrontierNonaddition, debugGoalFound, debugInitialNode, getDebug, getLastAddedToFrontier, getLastExpandedFromFrontier, getLastNotAddedToFrontier, getLastUnexpandedInFrontier, search, setDebug, solvable

Methods inherited from class java.lang.Object

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

Constructor Details

AStarSearcher

public AStarSearcher(Predicate<Node> goalTest, Function<Node,Double> heuristic, Function<State,Node> initializer)

Constructor for this class which does not maintain an explored set.

Parameters:

goalTest - A boolean-returning function checking whether a tree node contains a goal state.

heuristic - Heuristic function for this search application.

initializer - Creates an initial tree node from a search space element. Passed as-is to the primary constructor for this class, and thence to superclasses.

AStarSearcher

public AStarSearcher(Predicate<Node> goalTest, Function<Node,Double> heuristic, Function<Frontiers.PriorityQueue<Node>,ExploredSet<Node>> exploredSetFactory, Function<State,Node> initializer)

Primary constructor for this class; other constructor relay to this one. This constructor provides the basic priority queue implementation of the frontier to the superclass constructor.

Parameters:

goalTest - A boolean-returning function checking whether a tree node contains a goal state.

heuristic - Heuristic function for this search application.

exploredSetFactory - Structure used to manage adding elements to the frontier, in particular for avoiing duplication. Passed as-is to the primary constructor for this class, and thence to the parent constructor.

initializer - Creates an initial tree node from a search space element. Passed as-is to the primary constructor for this class, and thence to the parent constructor.