aa.core
Class MigrationManager

java.lang.Object
  java.lang.Thread
      aa.tool.SystemThread
          aa.core.MigrationManager

All Implemented Interfaces:

java.lang.Runnable

public class MigrationManager

extends SystemThread

This class specifies a Migration Manger to handle mobile actors.

History:

• February 19, 2004 - version 0.0.3
  • do minor modification.
• February 14, 2004 - version 0.0.2
  • debug the 'fetchClassFile' method.
• April 12, 2003 - version 0.0.1
  • create this file.

Version:

$Date: 2008/01/01 00:23:47 $ $Revision: 1.1 $

Author:

Myeong-Wuk Jang

Field Summary

private ActorManager	m_amActorManager The reference to the Actor Manager of this actor platform.
private ActorName	m_anPlatform The actor name of this actor platform.
private DelayedMessageManager	m_dmmDelayedMessageManager The reference to the Delayed Message Manager of this actor platform.
private MessageManager	m_mmMessageManager The reference to the Message Manager of this actor platform.
private Platform	m_pPlatform The reference to this actor platform.
private java.lang.String	m_strHostAddressOfPlatform The host address of this platform.
private java.util.TreeMap	m_tmMobileActorClasses The class data repository for mobile actors.

Fields inherited from class aa.tool.SystemThread

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Constructor Summary

MigrationManager(Platform p_pPlatform, ActorManager p_amActorManager)
Creates a Migration Manager.

Method Summary

private java.lang.Object	deserialize(java.lang.String p_strClassName, byte[] pp_baClass, byte[] p_baStream) Deserialize a byte stream into an object.
private byte[]	fetchClassFile(java.lang.String p_strClassName) Fetches the byte array of the specified class.
protected void	informMigrationEnd(ActorName p_anActor, java.lang.String p_strHostAddress) Informs that migration of a mobile actor ends.
protected void	informMigrationStart(ActorName p_anActor, java.lang.String p_strHostAddress) Informs that migration of a mobile actor starts.
protected void	init() Processes some necessay routines before entering the main loop in the 'run' method.
protected void	migrateActor(ActorName p_anActor, java.net.InetAddress p_iaDestHost) Moves the specified actor to another host.
protected void	processMessage(ActorMessage p_amMsg) Processes a communication messages.
private void	reactivateActor(ActorThread p_athread) Reactivates a mobile actor.
protected void	receiveActor(java.lang.String p_strClassName, byte[] p_baClass, byte[] p_baActor, ActorName p_anPlatform) Receives an actor.
private void	sendErrorMessage(ActorName p_anReceiver, java.lang.String p_strMsg) Sends an error message.
private byte[]	serialize(java.io.Serializable p_serObj) Serializes an object into a byte stream.
protected void	setDelayedMessageManager(DelayedMessageManager p_dmm) Sets the reference to the Delayed Message Manager.
protected void	setMessageManager(MessageManager p_mm) Sets the reference to the Message Manager.
protected void	uninit() Uninitializes this component.

Methods inherited from class aa.tool.SystemThread

deliverMessage, run

Methods inherited from class java.lang.Thread

activeCount, checkAccess, countStackFrames, currentThread, destroy, dumpStack, enumerate, getContextClassLoader, getName, getPriority, getThreadGroup, holdsLock, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, join, resume, setContextClassLoader, setDaemon, setName, setPriority, sleep, sleep, start, stop, stop, suspend, toString, yield

Methods inherited from class java.lang.Object

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

Field Detail

m_strHostAddressOfPlatform

private java.lang.String m_strHostAddressOfPlatform

The host address of this platform.

m_anPlatform

private ActorName m_anPlatform

The actor name of this actor platform.

m_tmMobileActorClasses

private java.util.TreeMap m_tmMobileActorClasses

The class data repository for mobile actors.

m_pPlatform

private Platform m_pPlatform

The reference to this actor platform.

m_amActorManager

private ActorManager m_amActorManager

The reference to the Actor Manager of this actor platform.

m_mmMessageManager

private MessageManager m_mmMessageManager

The reference to the Message Manager of this actor platform.

m_dmmDelayedMessageManager

private DelayedMessageManager m_dmmDelayedMessageManager

The reference to the Delayed Message Manager of this actor platform.

Constructor Detail

MigrationManager

public MigrationManager(Platform p_pPlatform,
                        ActorManager p_amActorManager)

Creates a Migration Manager.

Parameters:

p_pPlatform - the reference to this platform.

p_amActorManager - the reference to an Actor Manager.

Method Detail

init

protected void init()

Processes some necessay routines before entering the main loop in the 'run' method.
This is called by the 'run' method of the super-class (SystemThread).

Specified by:

init in class SystemThread

uninit

protected void uninit()

Uninitializes this component.
This method is called by the Actor Manager.

setMessageManager

protected void setMessageManager(MessageManager p_mm)

Sets the reference to the Message Manager.
This method is called by the Message Manager.

Parameters:

p_mm - the reference to the Message Manager.

setDelayedMessageManager

protected void setDelayedMessageManager(DelayedMessageManager p_dmm)

Sets the reference to the Delayed Message Manager.
This method is called by the Delayed Message Manager.

Parameters:

p_dmm - the reference to the Delayed Message Manager.

processMessage

protected void processMessage(ActorMessage p_amMsg)

Processes a communication messages.
The messages for the Migration Manager are delivered from the Actor Manager of this actor platform.

Specified by:

processMessage in class SystemThread

Parameters:

p_amMsg - an actor communication message.

sendErrorMessage

private void sendErrorMessage(ActorName p_anReceiver,
                              java.lang.String p_strMsg)

Sends an error message.

Parameters:

p_anReceiver - the name of the receiver actor.

p_strMsg - an error message.

fetchClassFile

private byte[] fetchClassFile(java.lang.String p_strClassName)
                       throws java.lang.ClassNotFoundException

Fetches the byte array of the specified class.

Parameters:

p_strClassName - the name of the specified class.

Returns:

the bytes of the class.

Throws:

java.lang.ClassNotFoundException - throw when the system cannot find the class.

serialize

private byte[] serialize(java.io.Serializable p_serObj)
                  throws java.io.IOException

Serializes an object into a byte stream.

Parameters:

p_serObj - the input serializable object.

Returns:

a byte stream corresponding to the specified object.

Throws:

java.io.IOException

deserialize

private java.lang.Object deserialize(java.lang.String p_strClassName,
                                     byte[] pp_baClass,
                                     byte[] p_baStream)
                              throws java.io.IOException,
                                     java.lang.ClassNotFoundException

Deserialize a byte stream into an object.

Parameters:

p_strClassName - the name of the specified class.

pp_baClass - the input byte stream for the class information.

p_baStream - the input byte stream for an instance of the class.

Returns:

an object corresponding to the specified byte stream.

Throws:

java.io.IOException

java.lang.ClassNotFoundException

reactivateActor

private void reactivateActor(ActorThread p_athread)

Reactivates a mobile actor.

Parameters:

p_athread - the reference to an Actor class.

migrateActor

protected void migrateActor(ActorName p_anActor,
                            java.net.InetAddress p_iaDestHost)
                     throws MigrateActorException

Moves the specified actor to another host.
This method is controlled by an actor thread.

Parameters:

p_anActor - the name of an actor to be moved.

p_iaDestHost - the Internet address of the destination host.

Throws:

MigrateActorException - it occurs when an exception happens during the actor migration.

receiveActor

protected void receiveActor(java.lang.String p_strClassName,
                            byte[] p_baClass,
                            byte[] p_baActor,
                            ActorName p_anPlatform)

Receives an actor.
This method is controlled by the Platform class.

Parameters:

p_strClassName - the class name of a mobile actor.

p_baClass - an input byte stream of the class.

p_baActor - an input byte stream of the actor.

p_anPlatform - the actor name of this platform.

informMigrationStart

protected void informMigrationStart(ActorName p_anActor,
                                    java.lang.String p_strHostAddress)

Informs that migration of a mobile actor starts.
This method is controlled by the Platform class.

Parameters:

p_anActor - the name of a mobile actor.

informMigrationEnd

protected void informMigrationEnd(ActorName p_anActor,
                                  java.lang.String p_strHostAddress)

Informs that migration of a mobile actor ends.
This method is controlled by the Platform class.

Parameters:

p_anActor - the name of a mobile actor.