org.glassfish.api.admin

Class AdminCommandLock

java.lang.Object

org.glassfish.api.admin.AdminCommandLock

@Service
@Singleton
public class AdminCommandLock
extends Object

The implementation of the admin command lock.

Author:

Bill Shannon, Chris Kasso

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	AdminCommandLock.SuspendStatus The status of a suspend command attempt.

Constructor Summary

Constructors

Constructor and Description
AdminCommandLock()

Method Summary

Methods

Modifier and Type	Method and Description
void	dumpState(Logger logger, Level level)
Lock	getLock(AdminCommand command) Return the appropriate Lock object for the specified command.
Lock	getLock(AdminCommand command, String owner) Return the appropriate Lock object for the specified command.
Lock	getLock(CommandLock.LockType type) Return the appropriate Lock object for the specified LockType.
String	getLockMessage() Get the message to be returned if the lock could not be acquired.
String	getLockOwner() Get the admin user id for the user who acquired the exclusive lock.
Date	getLockTimeOfAcquisition() Get the time the exclusive lock was acquired.
boolean	isSuspended() Indicates if commands are currently suspended.
Thread	resumeCommands() Release the lock allowing the DAS to accept commands.
static void	runWithSuspendedLock(Runnable r) Use this method to temporarily suspend the command lock during which other operations may be performed.
AdminCommandLock.SuspendStatus	suspendCommands(long timeout, String lockOwner) Lock the DAS from accepting any commands annotated with a SHARED or EXCLUSIVE CommandLock.
AdminCommandLock.SuspendStatus	suspendCommands(long timeout, String lockOwner, String message) Lock the DAS from accepting any commands annotated with a SHARED or EXCLUSIVE CommandLock.

Methods inherited from class java.lang.Object

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

Constructor Detail

AdminCommandLock

public AdminCommandLock()

Method Detail

getLock

public Lock getLock(CommandLock.LockType type)

Return the appropriate Lock object for the specified LockType. The returned lock has not been locked. If the LockType is not SHARED or EXCLUSIVE null is returned.

Parameters:

type - the LockType

Returns:

the Lock object to use, or null

dumpState

public void dumpState(Logger logger,
             Level level)

getLock

public Lock getLock(AdminCommand command)

Return the appropriate Lock object for the specified command. The returned lock has not been locked. If this command needs no lock, null is returned.

Parameters:

command - the AdminCommand object

Returns:

the Lock object to use, or null if no lock needed

getLock

public Lock getLock(AdminCommand command,
           String owner)
             throws AdminCommandLockTimeoutException,
                    AdminCommandLockException

Return the appropriate Lock object for the specified command. The returned lock has been locked. If this command needs no lock, null is returned.

Parameters:

command - the AdminCommand object

owner - the authority who requested the lock

Returns:

the Lock object to use, or null if no lock needed

Throws:

AdminCommandLockTimeoutException

AdminCommandLockException

getLockOwner

public String getLockOwner()

Get the admin user id for the user who acquired the exclusive lock. This does not imply the lock is still held.

Returns:

the admin user who acquired the lock

getLockMessage

public String getLockMessage()

Get the message to be returned if the lock could not be acquired.

Returns:

the message indicating why the domain is locked.

getLockTimeOfAcquisition

public Date getLockTimeOfAcquisition()

Get the time the exclusive lock was acquired. This does not imply the lock is still held.

Returns:

the time the lock was acquired

isSuspended

public boolean isSuspended()

Indicates if commands are currently suspended.

suspendCommands

public AdminCommandLock.SuspendStatus suspendCommands(long timeout,
                                             String lockOwner)

Lock the DAS from accepting any commands annotated with a SHARED or EXCLUSIVE CommandLock. This method will result in the acquisition of an EXCLUSIVE lock. This method will not return until the lock is acquired, it times out or an error occurs.

Parameters:

timeout - lock timeout in seconds

lockOwner - the user who acquired the lock

Returns:

status regarding acquisition of the lock

suspendCommands

public AdminCommandLock.SuspendStatus suspendCommands(long timeout,
                                             String lockOwner,
                                             String message)

Lock the DAS from accepting any commands annotated with a SHARED or EXCLUSIVE CommandLock. This method will result in the acquisition of an EXCLUSIVE lock. This method will not return until the lock is acquired, it times out or an error occurs.

Parameters:

timeout - lock timeout in seconds

lockOwner - the user who acquired the lock

message - message to return when a command is blocked

Returns:

status regarding acquisition of the lock

resumeCommands

public Thread resumeCommands()

Release the lock allowing the DAS to accept commands. This method may return before the lock is released. When the thread exits the lock will have been released.

Returns:

the thread maintaining the lock, null if the DAS is not in a suspended state. The caller may join() the thread to determine when the lock is released.

runWithSuspendedLock

public static void runWithSuspendedLock(Runnable r)

Use this method to temporarily suspend the command lock during which other operations may be performed. When the method returns the lock will be reestablished. This method must be invoked from the same thread which acquired the original lock.

Parameters:

r - A Runnable which will be invoked by the method after the lock is suspended