ai.libs.jaicore.search.algorithms.standard.bestfirst

Class BestFirst<I extends GraphSearchWithSubpathEvaluationsInput<N,A,V>,N,A,V extends java.lang.Comparable<V>>

java.lang.Object

ai.libs.jaicore.basic.algorithm.AAlgorithm<I,O>

ai.libs.jaicore.basic.algorithm.ASolutionCandidateIterator<I,O>

ai.libs.jaicore.basic.algorithm.AOptimizer<I,EvaluatedSearchGraphPath<N,A,V>,V>

ai.libs.jaicore.search.core.interfaces.AOptimalPathInORGraphSearch<I,N,A,V>

ai.libs.jaicore.search.algorithms.standard.bestfirst.BestFirst<I,N,A,V>

Type Parameters:

I -

N -

A -

V -

All Implemented Interfaces:

ai.libs.jaicore.basic.algorithm.IAlgorithm<I,EvaluatedSearchGraphPath<N,A,V>>, ai.libs.jaicore.basic.algorithm.IOptimizationAlgorithm<I,EvaluatedSearchGraphPath<N,A,V>,V>, ai.libs.jaicore.basic.algorithm.ISolutionCandidateIterator<I,EvaluatedSearchGraphPath<N,A,V>>, ai.libs.jaicore.basic.Cancelable, ai.libs.jaicore.basic.ILoggingCustomizable, IGraphSearch<I,EvaluatedSearchGraphPath<N,A,V>,N,A>, IOptimalPathInORGraphSearch<I,N,A,V>, IPathInORGraphSearch<I,EvaluatedSearchGraphPath<N,A,V>,N,A>, java.lang.Iterable<ai.libs.jaicore.basic.algorithm.events.AlgorithmEvent>, java.util.concurrent.Callable<EvaluatedSearchGraphPath<N,A,V>>, java.util.Iterator<ai.libs.jaicore.basic.algorithm.events.AlgorithmEvent>

Direct Known Subclasses:

AStar, StandardBestFirst

public class BestFirst<I extends GraphSearchWithSubpathEvaluationsInput<N,A,V>,N,A,V extends java.lang.Comparable<V>>
extends AOptimalPathInORGraphSearch<I,N,A,V>

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	BestFirst.ParentDiscarding

Field Summary

Fields

Modifier and Type	Field and Description
protected java.util.concurrent.atomic.AtomicInteger	activeJobs
protected int	additionalThreadsForNodeAttachment
protected boolean	checkGoalPropertyOnEntirePath
protected java.util.Map<N,Node<N,V>>	ext2int
protected GraphGenerator<N,A>	graphGenerator
protected INodeEvaluator<N,V>	nodeEvaluator
protected NodeGoalTester<N>	nodeGoalTester
protected java.util.Queue<Node<N,V>>	open
protected PathGoalTester<N>	pathGoalTester
protected java.util.Queue<EvaluatedSearchSolutionCandidateFoundEvent<N,A,V>>	pendingSolutionFoundEvents
protected RootGenerator<N>	rootGenerator
protected java.util.Queue<EvaluatedSearchGraphPath<N,A,V>>	solutions
protected SuccessorGenerator<N,A>	successorGenerator

Constructor Summary

Constructors

Constructor and Description
BestFirst(I problem)
BestFirst(IBestFirstConfig config, I problem)

Method Summary

Modifier and Type	Method and Description
protected void	afterExpansion(Node<N,V> node)
protected void	afterInitialization() BLOCK C: Hooks
protected void	afterSelection(Node<N,V> node)
protected void	beforeExpansion(Node<N,V> node)
protected boolean	beforeSelection()
void	bootstrap(java.util.Collection<Node<N,V>> initialNodes) This method can be used to create an initial graph different from just root nodes.
protected ai.libs.jaicore.basic.algorithm.events.AlgorithmEvent	expandNextNode() This method conducts the expansion of the next node.
int	getAdditionalThreadsForExpansion()
IBestFirstConfig	getConfig()
int	getCreatedCounter()
java.util.List<N>	getCurrentPathToNode(N node) BLOCK D: Getters and Setters
int	getExpandedCounter() Check how many times a node was expanded.
V	getFValue(N node)
V	getFValue(Node<N,V> node)
Node<N,V>	getInternalRepresentationOf(N node)
protected Node<N,V>	getLocalVersionOfNode(Node<N,V> node) This is relevant if we work with several copies of a node (usually if we need to copy the search space somewhere).
java.lang.String	getLoggerName()
java.lang.Object	getNodeAnnotation(N node, java.lang.String annotation)
java.util.Map<java.lang.String,java.lang.Object>	getNodeAnnotations(N node)
INodeEvaluator<N,V>	getNodeEvaluator()
java.util.List<Node<N,V>>	getOpen()
java.util.Queue<EvaluatedSearchGraphPath<N,A,V>>	getSolutionQueue()
int	getTimeoutForComputationOfF()
protected void	initGraph() This method setups the graph by inserting the root nodes.
protected void	insertNodeIntoLocalGraph(Node<N,V> node)
protected void	labelNode(Node<N,V> node)
protected Node<N,V>	newNode(Node<N,V> parent, N t2)
protected Node<N,V>	newNode(Node<N,V> parent, N t2, V evaluation)
NodeExpansionJobSubmittedEvent<N,A,V>	nextNodeExpansion()
EvaluatedSearchGraphPath<N,A,V>	nextSolutionThatDominatesOpen()
ai.libs.jaicore.basic.algorithm.events.AlgorithmEvent	nextWithException()
void	onFValueReceivedEvent(FValueEvent<V> event)
void	receiveNodeAnnotationEvent(NodeAnnotationEvent<N> event)
void	receiveRolloutEvent(RolloutEvent<N,V> event)
void	receiveSolutionCandidateAnnotationEvent(SolutionAnnotationEvent<N,A,V> event)
void	receiveSolutionCandidateEvent(EvaluatedSearchSolutionCandidateFoundEvent<N,A,V> solutionEvent)
protected EvaluatedSearchSolutionCandidateFoundEvent<N,A,V>	registerSolution(EvaluatedSearchGraphPath<N,A,V> solutionPath)
void	selectNodeForNextExpansion(N node)
protected void	selectNodeForNextExpansion(Node<N,V> node)
void	setLoggerName(java.lang.String name)
void	setOpen(java.util.Queue<Node<N,V>> collection)
void	setTimeoutForComputationOfF(int timeoutInMS, INodeEvaluator<N,V> timeoutEvaluator)
protected void	shutdown()
java.lang.String	toString()

Methods inherited from class ai.libs.jaicore.search.core.interfaces.AOptimalPathInORGraphSearch

getGraphGenerator, nextSolutionCandidateEvent

Methods inherited from class ai.libs.jaicore.basic.algorithm.AOptimizer

call, getBestSeenSolution, nextSolutionCandidate, setBestSeenSolution, updateBestSeenSolution

Methods inherited from class ai.libs.jaicore.basic.algorithm.ASolutionCandidateIterator

collectAllSolutions

Methods inherited from class ai.libs.jaicore.basic.algorithm.AAlgorithm

activate, announceTimeoutDetected, avoidReinterruptionOnShutdownOnCurrentThread, cancel, checkAndConductTermination, checkTermination, computeTimeoutAware, getActivationTime, getId, getInput, getNumCPUs, getRemainingTimeToDeadline, getState, getTimeout, getTimeoutPrecautionOffset, hasNext, hasThreadBeenInterruptedDuringShutdown, interruptThreadAsPartOfShutdown, isCanceled, isShutdownInitialized, isStopCriterionSatisfied, isTimeouted, iterator, next, post, registerActiveThread, registerListener, resolveShutdownInterruptOnCurrentThread, setConfig, setMaxNumThreads, setNumCPUs, setState, setTimeout, setTimeout, setTimeoutPrecautionOffset, terminate, unregisterActiveThread, unregisterThreadAndShutdown

Methods inherited from class java.lang.Object

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

Methods inherited from interface ai.libs.jaicore.basic.algorithm.ISolutionCandidateIterator

nextSolutionCandidate

Methods inherited from interface ai.libs.jaicore.basic.algorithm.IAlgorithm

call, getId, getInput, getNumCPUs, getTimeout, registerListener, setMaxNumThreads, setNumCPUs, setTimeout, setTimeout

Methods inherited from interface java.lang.Iterable

forEach, iterator, spliterator

Methods inherited from interface java.util.Iterator

forEachRemaining, hasNext, next, remove

Methods inherited from interface ai.libs.jaicore.basic.Cancelable

cancel

Field Detail

graphGenerator

protected final GraphGenerator<N,A> graphGenerator

rootGenerator

protected final RootGenerator<N> rootGenerator

successorGenerator

protected final SuccessorGenerator<N,A> successorGenerator

pathGoalTester

protected final PathGoalTester<N> pathGoalTester

nodeGoalTester

protected final NodeGoalTester<N> nodeGoalTester

nodeEvaluator

protected final INodeEvaluator<N,V extends java.lang.Comparable<V>> nodeEvaluator

checkGoalPropertyOnEntirePath

protected final boolean checkGoalPropertyOnEntirePath

solutions

protected final java.util.Queue<EvaluatedSearchGraphPath<N,A,V extends java.lang.Comparable<V>>> solutions

pendingSolutionFoundEvents

protected final java.util.Queue<EvaluatedSearchSolutionCandidateFoundEvent<N,A,V extends java.lang.Comparable<V>>> pendingSolutionFoundEvents

ext2int

protected final java.util.Map<N,Node<N,V extends java.lang.Comparable<V>>> ext2int

open

protected java.util.Queue<Node<N,V extends java.lang.Comparable<V>>> open

additionalThreadsForNodeAttachment

protected int additionalThreadsForNodeAttachment

activeJobs

protected final java.util.concurrent.atomic.AtomicInteger activeJobs

Constructor Detail

BestFirst

public BestFirst(I problem)

BestFirst

public BestFirst(IBestFirstConfig config,
                 I problem)

Method Detail

newNode

protected Node<N,V> newNode(Node<N,V> parent,
                            N t2)
                     throws java.lang.InterruptedException

Throws:

java.lang.InterruptedException

newNode

protected Node<N,V> newNode(Node<N,V> parent,
                            N t2,
                            V evaluation)
                     throws java.lang.InterruptedException

Throws:

java.lang.InterruptedException

labelNode

protected void labelNode(Node<N,V> node)
                  throws ai.libs.jaicore.basic.algorithm.exceptions.AlgorithmTimeoutedException,
                         ai.libs.jaicore.basic.algorithm.AlgorithmExecutionCanceledException,
                         java.lang.InterruptedException,
                         ai.libs.jaicore.basic.algorithm.exceptions.AlgorithmException

Throws:

ai.libs.jaicore.basic.algorithm.exceptions.AlgorithmTimeoutedException

ai.libs.jaicore.basic.algorithm.AlgorithmExecutionCanceledException

java.lang.InterruptedException

ai.libs.jaicore.basic.algorithm.exceptions.AlgorithmException

initGraph

protected void initGraph()
                  throws ai.libs.jaicore.basic.algorithm.exceptions.AlgorithmTimeoutedException,
                         ai.libs.jaicore.basic.algorithm.AlgorithmExecutionCanceledException,
                         java.lang.InterruptedException,
                         ai.libs.jaicore.basic.algorithm.exceptions.AlgorithmException

This method setups the graph by inserting the root nodes.

Throws:

java.lang.InterruptedException

ai.libs.jaicore.basic.algorithm.AlgorithmExecutionCanceledException

java.util.concurrent.TimeoutException

ai.libs.jaicore.basic.algorithm.exceptions.AlgorithmException

ai.libs.jaicore.basic.algorithm.exceptions.AlgorithmTimeoutedException

selectNodeForNextExpansion

protected void selectNodeForNextExpansion(Node<N,V> node)
                                   throws java.lang.InterruptedException

Throws:

java.lang.InterruptedException

expandNextNode

protected ai.libs.jaicore.basic.algorithm.events.AlgorithmEvent expandNextNode()
                                                                        throws java.lang.InterruptedException,
                                                                               ai.libs.jaicore.basic.algorithm.AlgorithmExecutionCanceledException,
                                                                               ai.libs.jaicore.basic.algorithm.exceptions.AlgorithmTimeoutedException,
                                                                               ai.libs.jaicore.basic.algorithm.exceptions.AlgorithmException

This method conducts the expansion of the next node. Unless the next node has been selected from outside, it selects the first node on OPEN (if OPEN is empty but active jobs are running, it waits until those terminate)

Returns:

Throws:

java.lang.InterruptedException

ai.libs.jaicore.basic.algorithm.AlgorithmExecutionCanceledException

java.util.concurrent.TimeoutException

ai.libs.jaicore.basic.algorithm.exceptions.AlgorithmException

ai.libs.jaicore.basic.algorithm.exceptions.AlgorithmTimeoutedException

registerSolution

protected EvaluatedSearchSolutionCandidateFoundEvent<N,A,V> registerSolution(EvaluatedSearchGraphPath<N,A,V> solutionPath)

Overrides:

registerSolution in class AOptimalPathInORGraphSearch<I extends GraphSearchWithSubpathEvaluationsInput<N,A,V>,N,A,V extends java.lang.Comparable<V>>

shutdown

protected void shutdown()

Overrides:

shutdown in class ai.libs.jaicore.basic.algorithm.AAlgorithm<I extends GraphSearchWithSubpathEvaluationsInput<N,A,V>,EvaluatedSearchGraphPath<N,A,V extends java.lang.Comparable<V>>>

receiveSolutionCandidateEvent

public void receiveSolutionCandidateEvent(EvaluatedSearchSolutionCandidateFoundEvent<N,A,V> solutionEvent)

receiveRolloutEvent

public void receiveRolloutEvent(RolloutEvent<N,V> event)

receiveSolutionCandidateAnnotationEvent

public void receiveSolutionCandidateAnnotationEvent(SolutionAnnotationEvent<N,A,V> event)

receiveNodeAnnotationEvent

public void receiveNodeAnnotationEvent(NodeAnnotationEvent<N> event)

insertNodeIntoLocalGraph

protected void insertNodeIntoLocalGraph(Node<N,V> node)
                                 throws java.lang.InterruptedException

Throws:

java.lang.InterruptedException

getLocalVersionOfNode

protected Node<N,V> getLocalVersionOfNode(Node<N,V> node)

This is relevant if we work with several copies of a node (usually if we need to copy the search space somewhere).

Parameters:

node -

Returns:

bootstrap

public void bootstrap(java.util.Collection<Node<N,V>> initialNodes)
               throws java.lang.InterruptedException

This method can be used to create an initial graph different from just root nodes. This can be interesting if the search is distributed and we want to search only an excerpt of the original one.

Parameters:

initialNodes -

Throws:

java.lang.InterruptedException

nextWithException

public ai.libs.jaicore.basic.algorithm.events.AlgorithmEvent nextWithException()
                                                                        throws java.lang.InterruptedException,
                                                                               ai.libs.jaicore.basic.algorithm.AlgorithmExecutionCanceledException,
                                                                               ai.libs.jaicore.basic.algorithm.exceptions.AlgorithmTimeoutedException,
                                                                               ai.libs.jaicore.basic.algorithm.exceptions.AlgorithmException

Throws:

java.lang.InterruptedException

ai.libs.jaicore.basic.algorithm.AlgorithmExecutionCanceledException

ai.libs.jaicore.basic.algorithm.exceptions.AlgorithmTimeoutedException

ai.libs.jaicore.basic.algorithm.exceptions.AlgorithmException

selectNodeForNextExpansion

public void selectNodeForNextExpansion(N node)
                                throws java.lang.InterruptedException

Throws:

java.lang.InterruptedException

nextNodeExpansion

public NodeExpansionJobSubmittedEvent<N,A,V> nextNodeExpansion()

nextSolutionThatDominatesOpen

public EvaluatedSearchGraphPath<N,A,V> nextSolutionThatDominatesOpen()
                                                              throws java.lang.InterruptedException,
                                                                     ai.libs.jaicore.basic.algorithm.AlgorithmExecutionCanceledException,
                                                                     java.util.concurrent.TimeoutException,
                                                                     ai.libs.jaicore.basic.algorithm.exceptions.AlgorithmException

Throws:

java.lang.InterruptedException

ai.libs.jaicore.basic.algorithm.AlgorithmExecutionCanceledException

java.util.concurrent.TimeoutException

ai.libs.jaicore.basic.algorithm.exceptions.AlgorithmException

afterInitialization

protected void afterInitialization()

BLOCK C: Hooks

beforeSelection

protected boolean beforeSelection()

afterSelection

protected void afterSelection(Node<N,V> node)

beforeExpansion

protected void beforeExpansion(Node<N,V> node)

afterExpansion

protected void afterExpansion(Node<N,V> node)

getCurrentPathToNode

public java.util.List<N> getCurrentPathToNode(N node)

BLOCK D: Getters and Setters

getNodeEvaluator

public INodeEvaluator<N,V> getNodeEvaluator()

getAdditionalThreadsForExpansion

public int getAdditionalThreadsForExpansion()

getTimeoutForComputationOfF

public int getTimeoutForComputationOfF()

setTimeoutForComputationOfF

public void setTimeoutForComputationOfF(int timeoutInMS,
                                        INodeEvaluator<N,V> timeoutEvaluator)

getOpen

public java.util.List<Node<N,V>> getOpen()

Returns:

the openCollection

getInternalRepresentationOf

public Node<N,V> getInternalRepresentationOf(N node)

setOpen

public void setOpen(java.util.Queue<Node<N,V>> collection)

Parameters:

open - the openCollection to set

getLoggerName

public java.lang.String getLoggerName()

Specified by:

getLoggerName in interface ai.libs.jaicore.basic.ILoggingCustomizable

Overrides:

getLoggerName in class AOptimalPathInORGraphSearch<I extends GraphSearchWithSubpathEvaluationsInput<N,A,V>,N,A,V extends java.lang.Comparable<V>>

setLoggerName

public void setLoggerName(java.lang.String name)

Specified by:

setLoggerName in interface ai.libs.jaicore.basic.ILoggingCustomizable

Overrides:

setLoggerName in class AOptimalPathInORGraphSearch<I extends GraphSearchWithSubpathEvaluationsInput<N,A,V>,N,A,V extends java.lang.Comparable<V>>

getSolutionQueue

public java.util.Queue<EvaluatedSearchGraphPath<N,A,V>> getSolutionQueue()

getExpandedCounter

public int getExpandedCounter()

Check how many times a node was expanded.

Returns:

A counter of how many times a node was expanded.

getCreatedCounter

public int getCreatedCounter()

getFValue

public V getFValue(N node)

getFValue

public V getFValue(Node<N,V> node)

getNodeAnnotations

public java.util.Map<java.lang.String,java.lang.Object> getNodeAnnotations(N node)

getNodeAnnotation

public java.lang.Object getNodeAnnotation(N node,
                                          java.lang.String annotation)

onFValueReceivedEvent

public void onFValueReceivedEvent(FValueEvent<V> event)

getConfig

public IBestFirstConfig getConfig()

Specified by:

getConfig in interface ai.libs.jaicore.basic.algorithm.IAlgorithm<I extends GraphSearchWithSubpathEvaluationsInput<N,A,V>,EvaluatedSearchGraphPath<N,A,V extends java.lang.Comparable<V>>>

Overrides:

getConfig in class ai.libs.jaicore.basic.algorithm.AAlgorithm<I extends GraphSearchWithSubpathEvaluationsInput<N,A,V>,EvaluatedSearchGraphPath<N,A,V extends java.lang.Comparable<V>>>

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object