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package protocols.implementations;
import java.util.ArrayList;
import java.util.Vector;
import core.VSMessage;
import protocols.VSAbstractProtocol;
/**
* The class VSRaftProtocol, a skeleton for a Raft-based protocol.
*
* @author Paul C. Buetow
*/
public class VSRaftProtocol extends VSAbstractProtocol {
/** The current Raft term. */
private int currentTerm;
/** The PID voted for in the current term. */
private int votedFor;
/** The number of votes received while acting as a candidate. */
private int votesReceived;
/** The current leader PID. */
private int leaderId;
/** True if this process currently acts as the leader. */
private boolean isLeader;
/** True if this process currently acts as a candidate. */
private boolean isCandidate;
/** The local time when the last heartbeat was observed. */
private long lastHeartbeatTime;
/** PIDs which still have to acknowledge the current operation. */
private ArrayList<Integer> ackPids;
/** The local log index. */
private int logIndex;
/** The last committed log index. */
private int commitIndex;
/**
* Instantiates a new Raft protocol skeleton.
*/
public VSRaftProtocol() {
super(VSAbstractProtocol.HAS_ON_SERVER_START);
setClassname(getClass().toString());
resetState();
}
/* (non-Javadoc)
* @see events.VSAbstractProtocol#onServerInit()
*/
public void onServerInit() {
Vector<Integer> vec = new Vector<Integer>();
vec.add(2);
vec.add(3);
initVector("pids", vec, "PIDs of participating follower processes");
initLong("heartbeatInterval", 1500, "Heartbeat interval", "ms");
initString("logEntry", "cmd1", "Log entry to replicate");
}
/* (non-Javadoc)
* @see events.VSAbstractProtocol#onClientInit()
*/
public void onClientInit() {
initLong("electionTimeout", 4000, "Base election timeout", "ms");
initLong("electionJitter", 2000, "Election timeout jitter", "ms");
}
/* (non-Javadoc)
* @see protocols.VSAbstractProtocol#onServerStart()
*/
public void onServerStart() {
}
/* (non-Javadoc)
* @see protocols.VSAbstractProtocol#onServerRecv(core.VSMessage)
*/
public void onServerRecv(VSMessage recvMessage) {
}
/* (non-Javadoc)
* @see protocols.VSAbstractProtocol#onClientRecv(core.VSMessage)
*/
public void onClientRecv(VSMessage recvMessage) {
}
/* (non-Javadoc)
* @see protocols.VSAbstractProtocol#onServerSchedule()
*/
public void onServerSchedule() {
}
/* (non-Javadoc)
* @see protocols.VSAbstractProtocol#onClientSchedule()
*/
public void onClientSchedule() {
}
/* (non-Javadoc)
* @see protocols.VSAbstractProtocol#onServerReset()
*/
public void onServerReset() {
resetState();
}
/* (non-Javadoc)
* @see protocols.VSAbstractProtocol#onClientReset()
*/
public void onClientReset() {
resetState();
}
/**
* Resets the shared Raft state to its initial values.
*/
private void resetState() {
currentTerm = 0;
votedFor = -1;
votesReceived = 0;
leaderId = -1;
isLeader = false;
isCandidate = false;
lastHeartbeatTime = 0;
logIndex = 0;
commitIndex = 0;
if (ackPids == null) {
ackPids = new ArrayList<Integer>();
} else {
ackPids.clear();
}
}
}
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