public abstract class

Prop

extends JunctionExtra
implements IProp

java.lang.Object
↳	edu.stanford.junction.api.activity.JunctionExtra
	↳	edu.stanford.junction.props2.Prop

Known Direct Subclasses

CollectionProp, PropDaemon

Known Indirect Subclasses

ListProp, SetProp

Class Overview

Note: The use of 'synchronized' is very deliberate. If you want to access the state of the prop, you must use the withState callback, which serializes your state read with respect to state changes resulting from addOperation or handleMessage.

Summary

Constants
boolean	COMPRESS_STATE_SYNC
String	EVT_ANY
String	EVT_CHANGE
String	EVT_SYNC
int	MODE_NORM
int	MODE_SYNC
int	MSG_HELLO
int	MSG_I_HAVE_STATE
int	MSG_SEND_ME_STATE
int	MSG_STATE_OPERATION
int	MSG_STATE_SYNC
int	MSG_WHO_HAS_STATE

Fields
protected boolean	active
protected long	bestSyncSeqNum
protected Vector<IPropChangeListener>	changeListeners
protected IPropState	cleanState
protected boolean	enableChangeEvents
protected String	lastOpUUID
protected int	mode
protected Vector<JSONObject>	opsSYNC
protected Vector<JSONObject>	pendingLocals
protected String	propName
protected String	propReplicaName
protected PropStats	propStats
protected long	sequenceNum
protected long	staleness
protected IPropState	state
protected String	syncId
protected Timer	taskTimer
protected long	timeOfLastHello
protected long	timeOfLastSyncRequest
protected String	uuid

Public Constructors
	Prop(String propName, String propReplicaName, IPropState state, long seqNum)
	Prop(String propName, String propReplicaName, IPropState state)
	Prop(String propName, IPropState state, long seqNum)
	Prop(String propName, IPropState state)

Public Methods
synchronized void	addChangeListener(IPropChangeListener listener)
synchronized void	addOperation(JSONObject operation) Add an operation to the state managed by this Prop, with prediction
void	afterActivityJoin()
boolean	beforeOnMessageReceived(MessageHeader h, JSONObject m) Returns true if the normal event handling should proceed; Return false to stop cascading.
PropStats	getAndDisableStats()
String	getPropName() The name of the prop at large.
String	getPropReplicaName()
long	getSequenceNum() The internal counter that tracks how many operations have been executed on this prop's state.
long	getStaleness()
abstract IProp	newFresh()
IProp	newKeepingListeners()
synchronized void	removeAllChangeListeners()
synchronized void	removeChangeListener(IPropChangeListener listener)
synchronized void	removeChangeListenersOfType(String type)
void	startCollectingStats()
JSONObject	stateToJSON()
String	stateToString()
synchronized <T> T	withState(IWithStateAction<T> action)

Protected Methods
void	assertTrue(String s, boolean cond)
synchronized void	broadcastSyncRequest()
synchronized void	dispatchChangeNotification(String evtType, Object o)
void	enterSYNCMode()
void	exitSYNCMode()
void	handleHello(JSONObject msg)
synchronized void	handleMessage(JSONObject msg)
void	handleReceivedOp(JSONObject opMsg) What to do with a newly arrived operation? Depends on mode of operation.
void	handleStateSyncMsg(JSONObject msg) Install state received from peer.
long	helloInterval()
boolean	isActive()
boolean	isSelfMsg(JSONObject msg)
void	logErr(String s)
void	logInfo(String s)
void	logState(String s)
JSONObject	newHelloMsg()
JSONObject	newIHaveStateMsg(String syncId)
JSONObject	newSendMeStateMsg(String syncId)
JSONObject	newStateOperationMsg(JSONObject op)
JSONObject	newStateSyncMsg(String syncId, boolean compress)
JSONObject	newWhoHasStateMsg(String syncId)
abstract IPropState	reifyState(JSONObject obj)
void	removePendingLocal(JSONObject opMsg)
synchronized void	sendHello()
void	sendMessageToProp(JSONObject m) Send a message to all prop-replicas in this prop
void	sendMessageToPropReplica(String actorId, JSONObject m) Send a message to the prop-replica hosted at the given actorId.
long	syncRequestInterval()

[Expand]

Inherited Methods

From class edu.stanford.junction.api.activity.JunctionExtra

From class java.lang.Object

From interface edu.stanford.junction.props2.IProp

Constants

protected static final boolean COMPRESS_STATE_SYNC

Constant Value: true

public static final String EVT_ANY

Constant Value: "*"

public static final String EVT_CHANGE

Constant Value: "change"

public static final String EVT_SYNC

Constant Value: "sync"

protected static final int MODE_NORM

Constant Value: 1 (0x00000001)

protected static final int MODE_SYNC

Constant Value: 2 (0x00000002)

public static final int MSG_HELLO

Constant Value: 6 (0x00000006)

public static final int MSG_I_HAVE_STATE

Constant Value: 3 (0x00000003)

public static final int MSG_SEND_ME_STATE

Constant Value: 4 (0x00000004)

public static final int MSG_STATE_OPERATION

Constant Value: 1 (0x00000001)

public static final int MSG_STATE_SYNC

Constant Value: 5 (0x00000005)

public static final int MSG_WHO_HAS_STATE

Constant Value: 2 (0x00000002)

Fields

protected boolean active

protected long bestSyncSeqNum

protected Vector<IPropChangeListener> changeListeners

protected IPropState cleanState

protected boolean enableChangeEvents

protected String lastOpUUID

protected int mode

protected Vector<JSONObject> opsSYNC

protected Vector<JSONObject> pendingLocals

protected String propName

protected String propReplicaName

protected PropStats propStats

protected long sequenceNum

protected long staleness

protected IPropState state

protected String syncId

protected Timer taskTimer

protected long timeOfLastHello

protected long timeOfLastSyncRequest

protected String uuid

Public Constructors

public Prop (String propName, String propReplicaName, IPropState state, long seqNum)

public Prop (String propName, String propReplicaName, IPropState state)

public Prop (String propName, IPropState state, long seqNum)

public Prop (String propName, IPropState state)

Public Methods

public synchronized void addChangeListener (IPropChangeListener listener)

public synchronized void addOperation (JSONObject operation)

Add an operation to the state managed by this Prop, with prediction

public void afterActivityJoin ()

public boolean beforeOnMessageReceived (MessageHeader h, JSONObject m)

Returns true if the normal event handling should proceed; Return false to stop cascading.

public PropStats getAndDisableStats ()

public String getPropName ()

The name of the prop at large. All peers must share this name.

public String getPropReplicaName ()

public long getSequenceNum ()

The internal counter that tracks how many operations have been executed on this prop's state. For a given state, this number should be the same at all peers.

public long getStaleness ()

public abstract IProp newFresh ()

public IProp newKeepingListeners ()

public synchronized void removeAllChangeListeners ()

public synchronized void removeChangeListener (IPropChangeListener listener)

public synchronized void removeChangeListenersOfType (String type)

public void startCollectingStats ()

public JSONObject stateToJSON ()

public String stateToString ()

public synchronized T withState (IWithStateAction<T> action)

Protected Methods

protected void assertTrue (String s, boolean cond)

protected synchronized void broadcastSyncRequest ()

protected synchronized void dispatchChangeNotification (String evtType, Object o)

protected void enterSYNCMode ()

protected void exitSYNCMode ()

protected void handleHello (JSONObject msg)

protected synchronized void handleMessage (JSONObject msg)

protected void handleReceivedOp (JSONObject opMsg)

What to do with a newly arrived operation? Depends on mode of operation. Note, we must take care to make sure there is no sharing between this.cleanState and this.state. This means copying operations that must be applied to both states!

Interfaces

Classes