edu.umass.cs.reconfiguration.reconfigurationpackets

Class StopEpoch<NodeIDType>

java.lang.Object

edu.umass.cs.protocoltask.json.ProtocolPacket<NodeIDType,ReconfigurationPacket.PacketType>

edu.umass.cs.reconfiguration.reconfigurationpackets.ReconfigurationPacket<NodeIDType>

edu.umass.cs.reconfiguration.reconfigurationpackets.BasicReconfigurationPacket<NodeIDType>

edu.umass.cs.reconfiguration.reconfigurationpackets.StopEpoch<NodeIDType>

Type Parameters:

NodeIDType -

All Implemented Interfaces:

Request, RequestIdentifier, Byteable, ProtocolEvent<ReconfigurationPacket.PacketType,java.lang.String>, ThresholdProtocolEvent<NodeIDType,ReconfigurationPacket.PacketType,java.lang.String>, ReconfigurableRequest, ReplicableRequest, Keyable<java.lang.String>, Summarizable

public class StopEpoch<NodeIDType>
extends BasicReconfigurationPacket<NodeIDType>
implements ReconfigurableRequest, ReplicableRequest

Author:

V. Arun

Nested Class Summary

Nested classes/interfaces inherited from class edu.umass.cs.reconfiguration.reconfigurationpackets.ReconfigurationPacket

ReconfigurationPacket.PacketType

Field Summary

Fields inherited from class edu.umass.cs.reconfiguration.reconfigurationpackets.BasicReconfigurationPacket

epochNumber, serviceName

Fields inherited from class edu.umass.cs.reconfiguration.reconfigurationpackets.ReconfigurationPacket

clientPacketTypes, HANDLER_METHOD_PREFIX, PACKET_TYPE, serverPacketTypes

Fields inherited from class edu.umass.cs.protocoltask.json.ProtocolPacket

type

Fields inherited from interface edu.umass.cs.reconfiguration.interfaces.ReconfigurableRequest

STOP

Fields inherited from interface edu.umass.cs.gigapaxos.interfaces.Request

NO_OP

Constructor Summary

Constructors

Constructor and Description
StopEpoch(org.json.JSONObject json, Stringifiable<NodeIDType> unstringer)
StopEpoch(NodeIDType initiator, java.lang.String name, int epochNumber)
StopEpoch(NodeIDType initiator, java.lang.String name, int epochNumber, boolean getFinalState, boolean executeStop)

Method Summary

Modifier and Type	Method and Description
long	getRequestID() The uniqueness of this identifier across all requests to a replica group is important for safety when PaxosConfig.PC.PREVENT_DOUBLE_EXECUTION is enabled as gigapaxos may otherwise assume that the duplicate request identifier corresponds to a retransmission and will send back the response if any corresponding to the first execution.
boolean	isStop()
boolean	needsCoordination()
void	setNeedsCoordination(boolean b) After this method returns, ReplicableRequest.needsCoordination() should subsequently return b.
boolean	shouldExecuteStop()
boolean	shouldGetFinalState()
org.json.JSONObject	toJSONObjectImpl()

Methods inherited from class edu.umass.cs.reconfiguration.reconfigurationpackets.BasicReconfigurationPacket

getEpochNumber, getRequestType, getServiceName, getSummary

Methods inherited from class edu.umass.cs.reconfiguration.reconfigurationpackets.ReconfigurationPacket

assertPacketTypeChecks, assertPacketTypeChecks, assertPacketTypeChecks, assertPacketTypeChecks, concatenate, getMessage, getPacketType, getPacketTypeCanonicalClassName, getPacketTypeClass, getPacketTypeClassName, getReconfigurationPacket, getReconfigurationPacket, getReconfigurationPacketSuppressExceptions, getReconfigurationPacketSuppressExceptions, getReconfigurationPacketType, getReconfigurationPacketType, isReconfigurationPacket, putPacketType, toBytes, toString

Methods inherited from class edu.umass.cs.protocoltask.json.ProtocolPacket

flip, getInitiator, getKey, getSender, getType, setKey, setSender, setType, toJSONObject

Methods inherited from class java.lang.Object

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

Methods inherited from interface edu.umass.cs.reconfiguration.interfaces.ReconfigurableRequest

getEpochNumber, getSummary

Methods inherited from interface edu.umass.cs.gigapaxos.interfaces.Request

getRequestType, getServiceName, toBytes, toString

Methods inherited from interface edu.umass.cs.utils.Summarizable

getSummary

Constructor Detail

StopEpoch

public StopEpoch(NodeIDType initiator,
                 java.lang.String name,
                 int epochNumber,
                 boolean getFinalState,
                 boolean executeStop)

Parameters:

initiator -

name -

epochNumber -

getFinalState -

executeStop -

StopEpoch

public StopEpoch(NodeIDType initiator,
                 java.lang.String name,
                 int epochNumber)

Parameters:

initiator -

name -

epochNumber -

StopEpoch

public StopEpoch(org.json.JSONObject json,
                 Stringifiable<NodeIDType> unstringer)
          throws org.json.JSONException

Parameters:

json -

unstringer -

Throws:

org.json.JSONException

Method Detail

toJSONObjectImpl

public org.json.JSONObject toJSONObjectImpl()
                                     throws org.json.JSONException

Overrides:

toJSONObjectImpl in class BasicReconfigurationPacket<NodeIDType>

Throws:

org.json.JSONException

isStop

public boolean isStop()

Specified by:

isStop in interface ReconfigurableRequest

Returns:

True if this request is a stop request.

shouldExecuteStop

public boolean shouldExecuteStop()

Returns:

True if stop must be coordinated.

needsCoordination

public boolean needsCoordination()

Specified by:

needsCoordination in interface ReplicableRequest

Returns:

True if this request needs to be coordinated, false otherwise.

setNeedsCoordination

public void setNeedsCoordination(boolean b)

Description copied from interface: ReplicableRequest

After this method returns, ReplicableRequest.needsCoordination() should subsequently return b. This method is invoked by AbstractReplicaCoordinator with a false argument just before coordinating the request so that coordinated packets are not coordinated again infinitely. For example, if a replica coordinator's coordination strategy is to simply flood the request to all replicas, there needs to be a way for a recipient of a copy of this already once coordinated request to know that it should not coordinate it again. This method provides AbstractReplicaCoordinator a placeholder in the application request to prevent such infinite coordination loops.

This method is now deprecated and does not need to be overridden by implementing classes. It's original purpose was really only to be able to easily do lazy propagation replica coordination without introducing an additional type (just to distinguish between the original request at the entry replica and the replicated request so as to avoid an infinite propagation loop), but introducing an additional type is the clean way to do this. Paxos for example already has its own types, so it doesn't need this method.

Specified by:

setNeedsCoordination in interface ReplicableRequest

Parameters:

b - True if subsequent invocations of ReplicableRequest.needsCoordination() must return true, false otherwise.

shouldGetFinalState

public boolean shouldGetFinalState()

Returns:

True if the epoch final state should be sent with the AckStopEpoch packet.

getRequestID

public long getRequestID()

Description copied from interface: RequestIdentifier

The uniqueness of this identifier across all requests to a replica group is important for safety when PaxosConfig.PC.PREVENT_DOUBLE_EXECUTION is enabled as gigapaxos may otherwise assume that the duplicate request identifier corresponds to a retransmission and will send back the response if any corresponding to the first execution. With PaxosConfig.PC.PREVENT_DOUBLE_EXECUTION disabled, the uniqueness is important for liveness as duplicate request identifiers may result in the client not receiving a response for the latter request; this is because gigapaxos stores request execution callbacks indexed by the request identifier, so there must be at most one outstanding request with a given identifier for a given replica group.

Specified by:

getRequestID in interface RequestIdentifier

Returns:

A unique request identifier for this request.