org.lsst.ccs.services

Class LocalAgentLockService

java.lang.Object

org.lsst.ccs.services.AbstractAgentLockServiceDelegate

org.lsst.ccs.services.LocalAgentLockService

All Implemented Interfaces:

AgentPresenceListener, AgentLockServiceDelegate

public class LocalAgentLockService
extends AbstractAgentLockServiceDelegate

Client side locking service, for a given agent. It is attached to an instance of Agent, which is any agent with type >= CONSOLE. It provides an API both for consoles that need to lock/unlock a WORKER subsystem, and for WORKER subsystem that need to check the validity of a lock attached with a command request. It encapsulates the communication protocol with the centralized LockManager subsystem.

Author:

LSST CCS Team

Field Summary

Fields inherited from class org.lsst.ccs.services.AbstractAgentLockServiceDelegate

agentLevelListeners, agentLevels, agentLockUpdateListeners, heldLocks, levelListenersSemaphore, lockLevelUpdate, lockListenersSemaphore, log, svc

Constructor Summary

Constructors

Constructor and Description
LocalAgentLockService(AgentLockService svc)

Method Summary

Modifier and Type	Method and Description
Map<String,AgentLock>	getLocks()
void	lockAgent(String agentName)
void	preStart()
void	setLevelForAgent(String agentName, int level) Set this agent's operational level for the given subsystem.
void	unlockAgent(String agentName)
boolean	validateLock(AgentLock lock)

Methods inherited from class org.lsst.ccs.services.AbstractAgentLockServiceDelegate

addAgentLevelListener, addAgentLockUpdateListener, connected, getAgent, getAgentStateService, getAllWorkerAgents, getHeldLocks, getLevelForAgent, getLockableAgents, getLockedAgents, getLockForAgent, notifyLevelListeners, notifyLockListeners, preInit, removeAgentLevelListener, removeAgentLockUpdateListener, setLevelInternal, setLockInternal

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.lsst.ccs.messaging.AgentPresenceListener

connecting, disconnecting

Constructor Detail

LocalAgentLockService

public LocalAgentLockService(AgentLockService svc)

Method Detail

setLevelForAgent

public void setLevelForAgent(String agentName,
                             int level)
                      throws UnauthorizedLevelException,
                             UnauthorizedLockException,
                             IOException

Set this agent's operational level for the given subsystem. If this agent does not hold a lock on the subsystem, this method will first attempt to acquire a lock on the subsystem. If successful, registered AgentLevelListener will be notified with the new level value

Parameters:

agentName - the subsystem for which to change the level

level - the level to set

Throws:

UnauthorizedLevelException - if the requested level cannot be set. This happens if this agent owns a lock on the given subsystem and that lock defines a maximum level that is lower than the requested level, or if this agent does not hold a lock on the given subsystem and this agent's default subsystem level is lower than the requested level.

UnauthorizedLockException - if the user is not allowed to acquire a lock on the specified Agent

IOException - if there was a communication problem on the buses.

lockAgent

public void lockAgent(String agentName)
               throws UnauthorizedLockException,
                      IOException

Throws:

UnauthorizedLockException

IOException

unlockAgent

public void unlockAgent(String agentName)
                 throws IOException

Throws:

IOException

validateLock

public boolean validateLock(AgentLock lock)

getLocks

public Map<String,AgentLock> getLocks()

preStart

public void preStart()