components/camel-salesforce/camel-salesforce-component/src/main/java/org/apache/camel/component/salesforce/internal/streaming/CometDReplayExtension.java

/**
 * Copyright (c) 2016, Salesforce Developers
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the copyright holder nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 **/
package org.apache.camel.component.salesforce.internal.streaming;

import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.atomic.AtomicBoolean;

import org.cometd.bayeux.Channel;
import org.cometd.bayeux.Message;
import org.cometd.bayeux.client.ClientSession;
import org.cometd.bayeux.client.ClientSession.Extension.Adapter;

/**
 * CometDReplayExtension, typical usages are the following:
 * {@code client.addExtension(new CometDReplayExtension<>(replayMap));}
 *
 * @author yzhao
 * @since 198 (Winter '16)
 */
public class CometDReplayExtension<V> extends Adapter {
    private static final String EXTENSION_NAME = "replay";
    private final ConcurrentMap<String, V> dataMap = new ConcurrentHashMap<>();
    private final AtomicBoolean supported = new AtomicBoolean();

    public CometDReplayExtension(Map<String, V> dataMap) {
        this.dataMap.putAll(dataMap);
    }

    @Override
    @SuppressWarnings("unchecked")
    public boolean rcv(ClientSession session, Message.Mutable message) {
        Object data = message.get(EXTENSION_NAME);
        if (this.supported.get() && data != null) {
            try {
                dataMap.put(message.getChannel(), (V) data);
            } catch (ClassCastException e) {
                return false;
            }
        }
        return true;
    }

    @Override
    public boolean rcvMeta(ClientSession session, Message.Mutable message) {
        switch (message.getChannel()) {
        case Channel.META_HANDSHAKE:
            Map<String, Object> ext = message.getExt(false);
            this.supported.set(ext != null && Boolean.TRUE.equals(ext.get(EXTENSION_NAME)));
            break;
        default:
            break;
        }
        return true;
    }

    @Override
    public boolean sendMeta(ClientSession session, Message.Mutable message) {
        switch (message.getChannel()) {
        case Channel.META_HANDSHAKE:
            message.getExt(true).put(EXTENSION_NAME, Boolean.TRUE);
            break;
        case Channel.META_SUBSCRIBE:
            if (supported.get()) {
                message.getExt(true).put(EXTENSION_NAME, dataMap);
            }
            break;
        default:
            break;
        }
        return true;
    }
}