edu.umass.cs.gigapaxos.paxospackets.SyncDecisionsPacket.java Source code

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Here is the source code for edu.umass.cs.gigapaxos.paxospackets.SyncDecisionsPacket.java

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/*
 * Copyright (c) 2015 University of Massachusetts
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you
 * may not use this file except in compliance with the License. You
 * may obtain a copy of the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * permissions and limitations under the License.
 * 
 * Initial developer(s): V. Arun
 */
package edu.umass.cs.gigapaxos.paxospackets;

import edu.umass.cs.utils.Util;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.util.ArrayList;

/**
 * @author arun
 *
 *         A sync reply packet contains commits missing at the sending node
 *         (nodeID). The receiver is expected to send to the sender the commits
 *         it is reporting as missing in this sync reply.
 */
@SuppressWarnings("javadoc")
public final class SyncDecisionsPacket extends PaxosPacket {

    /**
     * Node sending the sync decisions request.
     */
    public final int nodeID;
    /**
     * Maximum slot up to which decisions have been received by the sending
     * node.
     */
    public final int maxDecisionSlot;
    /**
     * Missing decision slot numbers beyond {@link #maxDecisionSlot
     * maxDecisionSlot}.
     */
    public final ArrayList<Integer> missingSlotNumbers;

    public SyncDecisionsPacket(int nodeID, int maxDecisionSlot, ArrayList<Integer> missingSlotNumbers,
            boolean flag) {
        super((PaxosPacket) null);
        this.nodeID = nodeID;
        this.maxDecisionSlot = maxDecisionSlot;
        this.missingSlotNumbers = missingSlotNumbers;
        this.packetType = PaxosPacket.PaxosPacketType.SYNC_DECISIONS_REQUEST;
    }

    public SyncDecisionsPacket(JSONObject json) throws JSONException {
        super(json);
        this.nodeID = json.getInt(PaxosPacket.NodeIDKeys.SNDR.toString());
        this.maxDecisionSlot = json.getInt(PaxosPacket.Keys.MAX_S.toString());
        if (json.has(PaxosPacket.Keys.MISS.toString()))
            missingSlotNumbers = Util
                    .JSONArrayToArrayListInteger(json.getJSONArray(PaxosPacket.Keys.MISS.toString()));
        else
            missingSlotNumbers = null;
        assert (PaxosPacket.getPaxosPacketType(json) == PaxosPacketType.SYNC_DECISIONS_REQUEST
                || PaxosPacket.getPaxosPacketType(json) == PaxosPacketType.CHECKPOINT_REQUEST);
        this.packetType = PaxosPacketType.SYNC_DECISIONS_REQUEST;
    }

    @Override
    public JSONObject toJSONObjectImpl() throws JSONException {
        JSONObject json = new JSONObject();
        json.put(PaxosPacket.NodeIDKeys.SNDR.toString(), nodeID);
        json.put(PaxosPacket.Keys.MAX_S.toString(), maxDecisionSlot);
        if (missingSlotNumbers != null && missingSlotNumbers.size() > 0)
            json.put(PaxosPacket.Keys.MISS.toString(), new JSONArray(missingSlotNumbers));
        return json;
    }

    @Override
    protected String getSummaryString() {
        return nodeID + "[" + this.missingSlotNumbers.get(0) + ", "
                + this.missingSlotNumbers.get(this.missingSlotNumbers.size() - 1) + "]";
    }
}