com.arjuna.ats.arjuna.recovery

Class RecoveryManager

java.lang.Object

com.arjuna.ats.arjuna.recovery.RecoveryManager

public class RecoveryManager
extends Object

The RecoveryManager daemon.

Field Summary

Fields

Modifier and Type	Field and Description
static int	DIRECT_MANAGEMENT In this mode the recovery manager does not run periodically and will only work if driven through messages or via the scan operation if it is embedded.
static int	INDIRECT_MANAGEMENT In this mode the recovery manager runs periodically but may also be driven through messages or via the scan operation if it is embedded.

Method Summary

Methods

Modifier and Type	Method and Description
void	addModule(RecoveryModule module) Add a recovery module to the system.
static void	delayRecoveryManagerThread() Delay the start of the recovery manager thread when creating an indirect recovery manager.
static Socket	getClientSocket() Obtain a client connection to the recovery manager
Vector<RecoveryModule>	getModules() Obtain a snapshot list of available recovery modules.
static InetAddress	getRecoveryManagerHost()
static int	getRecoveryManagerPort()
void	initialize() If the recovery manager has been shutdown previously then recreate it in the same mode as before.
static void	main(String[] args) Run the RecoveryManager.
static RecoveryManager	manager() Obtain a reference to the RecoveryManager singleton.
static RecoveryManager	manager(int mode) Obtain a reference to the RecoveryManager singleton.
int	mode() Indicates what mode (INDIRECT_MANAGEMENT or DIRECT_MANAGEMENT) the recovery manager is configured for.
void	removeAllModules(boolean waitOnScan) Remove all modules.
void	removeModule(RecoveryModule module, boolean waitOnScan) Remove a recovery module from the system.
void	resume()
void	scan() Force a recovery scan now.
void	scan(RecoveryScan callback) Force a recovery scan now.
void	startRecoveryManagerThread() Start the recovery manager thread.
void	suspend(boolean async) Suspend the recovery manager.
void	terminate() Terminate and cleanup the recovery manager.
void	terminate(boolean async) Terminate and cleanup the recovery manager.
void	waitForTermination() wait for the recovery thread to be shutdown.

Methods inherited from class java.lang.Object

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

Field Detail

INDIRECT_MANAGEMENT

public static final int INDIRECT_MANAGEMENT

In this mode the recovery manager runs periodically but may also be driven through messages or via the scan operation if it is embedded.

See Also:

Constant Field Values

DIRECT_MANAGEMENT

public static final int DIRECT_MANAGEMENT

In this mode the recovery manager does not run periodically and will only work if driven through messages or via the scan operation if it is embedded.

See Also:

Constant Field Values

Method Detail

manager

public static final RecoveryManager manager()
                                     throws IllegalArgumentException

Obtain a reference to the RecoveryManager singleton. If it hasn't been created yet then it will be. The manager will be created in the INDIRECT_MANAGEMENT mode.

Returns:

the manager.

Throws:

IllegalArgumentException - thrown if the manager has already been created in a different mode to that requested.

manager

public static final RecoveryManager manager(int mode)
                                     throws IllegalArgumentException

Obtain a reference to the RecoveryManager singleton. If it hasn't been created yet then it will be. The manager can be created in a management mode defined by the parameter.

Parameters:

mode - the management mode for the manager.

Returns:

the manager.

Throws:

IllegalArgumentException - thrown if the manager has already been created in a different mode to that requested.

delayRecoveryManagerThread

public static void delayRecoveryManagerThread()

Delay the start of the recovery manager thread when creating an indirect recovery manager.

scan

public final void scan()

Force a recovery scan now. This is a blocking operation and will only return once the recovery scan has completed.

Throws:

IllegalStateException - if the recovery manager has been shutdown.

scan

public final void scan(RecoveryScan callback)

Force a recovery scan now. This is a non-blocking operation and will return immediately. Notification of completion of the scan is done through the RecoveryScan object.

Parameters:

callback - callback The callback mechanism used to inform users that the scan has completed. If this is null then no callback will happen and asynchronous scanning will occur.

Throws:

IllegalStateException - if the recovery manager has been shutdown.

terminate

public final void terminate()

Terminate and cleanup the recovery manager. There is no going back from this. This is a synchronous operation so return means that the recovery has completed.

Throws:

IllegalStateException - if the recovery manager has been shutdown.

terminate

public final void terminate(boolean async)

Terminate and cleanup the recovery manager. There is no going back from this. Can be called synchronous or asynchronously. If you have any intention of restarting the recovery manager later then you MUST use the async=false option.

Parameters:

async - false means wait for any recovery scan in progress to complete.

Throws:

IllegalStateException - if the recovery manager has been shutdown.

initialize

public final void initialize()

If the recovery manager has been shutdown previously then recreate it in the same mode as before. Otherwise ignore.

waitForTermination

public void waitForTermination()

wait for the recovery thread to be shutdown. n.b. this will not return unless and until shutdown is called.

Throws:

IllegalStateException - if the recovery manager has been shutdown.

suspend

public void suspend(boolean async)

Suspend the recovery manager. If the recovery manager is in the process of doing recovery scans then it will be suspended afterwards, in order to preserve data integrity.

Parameters:

async - false means wait for the recovery manager to finish any scans before returning.

Throws:

IllegalStateException - if the recovery manager has been shutdown.

resume

public void resume()

Throws:

IllegalStateException - if the recovery manager has been shutdown.

startRecoveryManagerThread

public void startRecoveryManagerThread()

Start the recovery manager thread.

Throws:

IllegalStateException - if the recovery manager has been shutdown.

addModule

public final void addModule(RecoveryModule module)

Add a recovery module to the system.

Parameters:

module - module The module to add.

Throws:

IllegalStateException - if the recovery manager has been shutdown.

removeModule

public final void removeModule(RecoveryModule module,
                boolean waitOnScan)

Remove a recovery module from the system.

Parameters:

module - The module to remove.

waitOnScan - true if the remove operation should wait for any in-progress scan to complete

Throws:

IllegalStateException - if the recovery manager has been shutdown.

removeAllModules

public final void removeAllModules(boolean waitOnScan)

Remove all modules. WARNING: Use with extreme care as this will stop recovery from doing anything!

getModules

public final Vector<RecoveryModule> getModules()

Obtain a snapshot list of available recovery modules.

Returns:

a snapshot list of the currently installed recovery modules

Throws:

IllegalStateException - if the recovery manager has been shutdown.

mode

public final int mode()

Indicates what mode (INDIRECT_MANAGEMENT or DIRECT_MANAGEMENT) the recovery manager is configured for.

Returns:

the management mode.

getRecoveryManagerHost

public static InetAddress getRecoveryManagerHost()
                                          throws UnknownHostException

Throws:

UnknownHostException

getRecoveryManagerPort

public static int getRecoveryManagerPort()

getClientSocket

public static Socket getClientSocket()
                              throws IOException

Obtain a client connection to the recovery manager

Returns:

a bound client socket connection to the recovery manager

Throws:

IOException

main

public static void main(String[] args)

Run the RecoveryManager. See Administration manual for details.