edu.umass.cs.reconfiguration.reconfigurationpackets.RequestActiveReplicas.java Source code

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Here is the source code for edu.umass.cs.reconfiguration.reconfigurationpackets.RequestActiveReplicas.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.reconfiguration.reconfigurationpackets;

import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.UnknownHostException;
import java.util.HashSet;
import java.util.Set;

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

import edu.umass.cs.nio.JSONNIOTransport;
import edu.umass.cs.nio.interfaces.Stringifiable;
import edu.umass.cs.nio.nioutils.StringifiableDefault;

/**
 * @author V. Arun
 * 
 *         This class has an additional field for returning the set of active
 *         replicas in addition to the fields in the generic
 *         ClientReconfigurationPacket. This class is used to both request for
 *         and return the set of active replicas for a name. If the field
 *         actives is null, it is implicitly interpreted as a request, else as a
 *         response.
 */
public class RequestActiveReplicas extends ClientReconfigurationPacket {

    /**
     *
     */
    public static enum Keys {
        /**
         * Active replica set.
         */
        ACTIVE_REPLICAS,

    };

    /**
     * Unstringer for InetSocketAddress of sender.
     */
    public static final Stringifiable<InetSocketAddress> unstringer = new StringifiableDefault<InetSocketAddress>(
            new InetSocketAddress(InetAddress.getLoopbackAddress(), 0));

    private Set<InetSocketAddress> actives = null;

    /**
     * @param name
     */
    public RequestActiveReplicas(String name) {
        this(null, name, 0);
    }

    /**
     * @param initiator
     * @param name
     * @param epochNumber
     */
    public RequestActiveReplicas(InetSocketAddress initiator, String name, int epochNumber) {
        super(initiator, ReconfigurationPacket.PacketType.REQUEST_ACTIVE_REPLICAS, name, epochNumber);
        this.actives = null;
    }

    /**
     * @param json
     * @param unstringer
     * @throws JSONException
     */
    public RequestActiveReplicas(JSONObject json, Stringifiable<?> unstringer) throws JSONException {
        super(json, RequestActiveReplicas.unstringer); // ignores arg unstringer
        // assertion may not hold with String packet demultiplexer
        //assert(this.getSender()!=null);
        //this.setSender(JSONNIOTransport.getSenderAddress(json));

        JSONArray jsonArray = json.has(Keys.ACTIVE_REPLICAS.toString())
                ? json.getJSONArray(Keys.ACTIVE_REPLICAS.toString())
                : null;
        if (jsonArray != null) {
            this.actives = new HashSet<InetSocketAddress>();
            for (int i = 0; jsonArray != null && i < jsonArray.length(); i++)
                this.actives.add(RequestActiveReplicas.unstringer.valueOf(jsonArray.get(i).toString()));
        }
    }

    /**
     * @param json
     * @throws JSONException
     */
    public RequestActiveReplicas(JSONObject json) throws JSONException {
        this(json, null);
    }

    public JSONObject toJSONObjectImpl() throws JSONException {
        JSONObject json = super.toJSONObjectImpl();
        if (this.actives != null)
            json.put(Keys.ACTIVE_REPLICAS.toString(), new JSONArray(this.actives));
        return json;
    }

    /**
     * @param replicas
     * @return {@code this} with active replicas set to {@code replicas}.
     */
    public ClientReconfigurationPacket setActives(Set<InetSocketAddress> replicas) {
        this.actives = replicas;
        return this;
    }

    /**
     * @return Active replica socket addresses.
     */
    public Set<InetSocketAddress> getActives() {
        return this.actives;
    }

    public static void main(String[] args) {
        String[] addrs = { "128.119.240.21" };
        int[] ports = { 3245 };
        assert (addrs.length == ports.length);
        InetSocketAddress[] isaddrs = new InetSocketAddress[addrs.length];
        try {
            for (int i = 0; i < addrs.length; i++) {
                isaddrs[i] = new InetSocketAddress(InetAddress.getByName(addrs[i]), ports[i]);
            }
            String name = "name";
            InetSocketAddress sender = new InetSocketAddress(InetAddress.getLoopbackAddress(), 1234);
            RequestActiveReplicas req1 = new RequestActiveReplicas(sender, name, 0);
            System.out.println(req1);
            JSONObject json1;
            json1 = req1.toJSONObject();
            RequestActiveReplicas req2 = new RequestActiveReplicas(json1, null);
            System.out.println(req2);
        } catch (UnknownHostException | JSONException e) {
            e.printStackTrace();
        }
    }
}