cz.cuni.amis.pogamut.ut2004multi.communication.module

Class SharedKnowledgeDatabase

java.lang.Object

cz.cuni.amis.pogamut.ut2004multi.communication.module.SharedKnowledgeDatabase

public class SharedKnowledgeDatabase
extends Object

Manages shared knowledge for agent teams. The class is managed - meaning only one instance can exist for each team. Beware that this class can only be used when you are running all your agents from a single JVM. This means you have to used the new MultipleAgentRunner to run your team. Then each agent has to register with this database by calling addAgent(IAgentId, IVisionWorldView, int) with the specific parameters. After that, the database should be ready for use.

Author:

srlok, Jimmy

Field Summary

Fields

Modifier and Type	Field and Description
protected cz.cuni.amis.utils.concurrency.AtomicLongList	agentLockTimes agentLockTimes[agentNumber] == lock time the agent owns (or -1 for no-lock)
protected Map<IAgentId,IVisionWorldView>	agentWorldViews Maps the agentIds to their concrete worldViews - these are then used in getting the local object information and to attach the listeners
protected Map<IAgentId,TimeKey>	currentTimeKeys The current TimeKey handled by an agent
protected cz.cuni.amis.utils.maps.HashMapMap<WorldObjectId,PropertyId,ISharedProperty>	currSharedProperties The most recent versions of sharedProperties
protected HashMap<TimeKey,Set<IAgentId>>	heldKeys Currently 'locked' timeKeys (with agents locking the keys) - we need to keep objects for those
protected static Map<Integer,SharedKnowledgeDatabase>	instances Team number to instance.
protected Map<WorldObjectId,Long>	lastUpdateTime Holds the last time when an update event was recieved from any agent for each object
protected Map<IAgentId,Set<IWorldObjectEventListener>>	listeners Remembers all the listeners added for an agent, this is needed to properly remove them when a agent unregisters from the database
protected cz.cuni.amis.utils.maps.SyncHashMap<IAgentId,Integer>	registeredAgents Which agents are registered here mapped to their agent-numbers.
protected Set<Class>	registeredClasses Classes for which the database processes events
protected cz.cuni.amis.utils.maps.WeakHashTriMap<TimeKey,WorldObjectId,PropertyId,ISharedProperty>	sharedProperties Just holds the weakly referenced shared properties for the worldObjects
protected int	team Team number for which the shared knowledge database was constructed for.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	SharedKnowledgeDatabase(int team)

Method Summary

Methods

Modifier and Type	Method and Description
void	addAgent(IAgentId id, IVisionWorldView agentWorldView, int team) Registers an agent to the database - it will process it's relevant events from now on.
protected void	addClassListener(IVisionWorldView wv, Class c, IAgentId agentId) Helper method to add a single objectEventListener for Class c to a specific WorldView
void	addObjectClass(Class c) Registers the provided class as a class of interest.
protected void	addTimeLock(TimeKey timeKey, IAgentId id) Locks the specified time and all greater times with the agentId
static SharedKnowledgeDatabase	get(int team) Returns the only instance of SharedKnowledgeDatabase for the specified team.
IWorldObject	getObject(WorldObjectId id, IAgentId agentId) Returns the specified object with the team shared knowledge put in
protected void	processObjEvent(IWorldObjectEvent<IWorldObject> event, IAgentId agentId) Handles processing of an object event raised on any of the worldViews.
boolean	removeAgent(IAgentId id) Unregister the agent from the database -> the database will no longer process events from this agent.
boolean	removeObjectClass(Class c) Stops processing events for the specified class.
protected void	removeTimeLock(TimeKey timeKey, IAgentId id) Removes a single lock for this timeKey, if it is the last, the whole lock is removed

Methods inherited from class java.lang.Object

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

Field Detail

instances

protected static Map<Integer,SharedKnowledgeDatabase> instances

Team number to instance.

registeredAgents

protected cz.cuni.amis.utils.maps.SyncHashMap<IAgentId,Integer> registeredAgents

Which agents are registered here mapped to their agent-numbers.

team

protected int team

Team number for which the shared knowledge database was constructed for.

agentLockTimes

protected cz.cuni.amis.utils.concurrency.AtomicLongList agentLockTimes

agentLockTimes[agentNumber] == lock time the agent owns (or -1 for no-lock)

agentWorldViews

protected Map<IAgentId,IVisionWorldView> agentWorldViews

Maps the agentIds to their concrete worldViews - these are then used in getting the local object information and to attach the listeners

listeners

protected Map<IAgentId,Set<IWorldObjectEventListener>> listeners

Remembers all the listeners added for an agent, this is needed to properly remove them when a agent unregisters from the database

sharedProperties

protected cz.cuni.amis.utils.maps.WeakHashTriMap<TimeKey,WorldObjectId,PropertyId,ISharedProperty> sharedProperties

Just holds the weakly referenced shared properties for the worldObjects

currSharedProperties

protected cz.cuni.amis.utils.maps.HashMapMap<WorldObjectId,PropertyId,ISharedProperty> currSharedProperties

The most recent versions of sharedProperties

lastUpdateTime

protected Map<WorldObjectId,Long> lastUpdateTime

Holds the last time when an update event was recieved from any agent for each object

heldKeys

protected HashMap<TimeKey,Set<IAgentId>> heldKeys

Currently 'locked' timeKeys (with agents locking the keys) - we need to keep objects for those

currentTimeKeys

protected Map<IAgentId,TimeKey> currentTimeKeys

The current TimeKey handled by an agent

registeredClasses

protected Set<Class> registeredClasses

Classes for which the database processes events

Constructor Detail

SharedKnowledgeDatabase

protected SharedKnowledgeDatabase(int team)

Method Detail

get

public static SharedKnowledgeDatabase get(int team)

Returns the only instance of SharedKnowledgeDatabase for the specified team.

Parameters:

team -

Returns:

addTimeLock

protected void addTimeLock(TimeKey timeKey,
               IAgentId id)

Locks the specified time and all greater times with the agentId

removeTimeLock

protected void removeTimeLock(TimeKey timeKey,
                  IAgentId id)

Removes a single lock for this timeKey, if it is the last, the whole lock is removed

Parameters:

timeKey -

id -

addAgent

public void addAgent(IAgentId id,
            IVisionWorldView agentWorldView,
            int team)

Registers an agent to the database - it will process it's relevant events from now on.

Parameters:

id -

agentWorldView -

team -

addObjectClass

public void addObjectClass(Class c)

Registers the provided class as a class of interest. The knowledge database will register listeners on all agent worldViews and will start processing events from the worldViews to collect shared information.

Parameters:

c -

removeObjectClass

public boolean removeObjectClass(Class c)

Stops processing events for the specified class. If the class is not registered, no change is made.

Parameters:

c - class to process events for

Returns:

false if the class was not registered

removeAgent

public boolean removeAgent(IAgentId id)

Unregister the agent from the database -> the database will no longer process events from this agent. The method also removes all listeners created by the database on the agent's worldview.

Parameters:

id -

team -

Returns:

getObject

public IWorldObject getObject(WorldObjectId id,
                     IAgentId agentId)

Returns the specified object with the team shared knowledge put in

Parameters:

id -

agentId -

Returns:

addClassListener

protected void addClassListener(IVisionWorldView wv,
                    Class c,
                    IAgentId agentId)

Helper method to add a single objectEventListener for Class c to a specific WorldView

Parameters:

wv -

c -

agentId -

processObjEvent

protected void processObjEvent(IWorldObjectEvent<IWorldObject> event,
                   IAgentId agentId)

Handles processing of an object event raised on any of the worldViews. This method will update all the shared properties correctly and also uses the event information to adjust the heldTimeKeys

Parameters:

event -