com.akanoo.client.atmosphere.CometListener.java Source code

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Here is the source code for com.akanoo.client.atmosphere.CometListener.java

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/* Copyright 2012 Fabian Gebert and Michael Gorski.
 *
 * 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.
 */
package com.akanoo.client.atmosphere;

import java.util.List;

import org.atmosphere.gwt.client.AtmosphereClient;
import org.atmosphere.gwt.client.AtmosphereGWTSerializer;
import org.atmosphere.gwt.client.AtmosphereListener;
import org.atmosphere.gwt.client.impl.WebSocketCometTransport;

import com.akanoo.client.Akanoo;
import com.akanoo.client.dto.Message;
import com.akanoo.client.dto.Message.MessageReader;
import com.akanoo.client.dto.MessageConstants;
import com.akanoo.client.dto.Sendable;
import com.akanoo.client.dto.SendableConverter;
import com.akanoo.client.events.CometBeforeDisconnectedEvent;
import com.akanoo.client.events.CometConnectedEvent;
import com.akanoo.client.events.CometDisconnectedEvent;
import com.akanoo.client.events.CometErrorEvent;
import com.akanoo.client.events.CometHeartbeatEvent;
import com.akanoo.client.events.CometMessageEvent;
import com.akanoo.client.messages.Languages;
import com.google.gwt.core.client.GWT;
import com.google.gwt.user.client.Window;
import com.google.gwt.user.client.rpc.StatusCodeException;
import com.google.inject.Inject;
import com.google.web.bindery.event.shared.EventBus;

public class CometListener {

    private static final boolean ENFORCE_WEBSOCKET = false;
    private static final boolean SUPPORT_WEBSOCKET = true;

    @Inject
    EventBus eventBus;

    @Inject
    Languages messages;

    @Inject
    private MessageReader messageReader;

    @Inject
    private SendableConverter sendableConverter;

    AtmosphereClient client;

    public boolean connected;

    private boolean initialized;

    private class MyCometListener implements AtmosphereListener {

        @Override
        public void onConnected(int heartbeat, int connectionID) {
            GWT.log("comet.connected [" + heartbeat + ", " + connectionID + "]");

            if (!connected) {
                connected = true;
                eventBus.fireEvent(new CometConnectedEvent());

                sendInitializer();
            }
        }

        @Override
        public void onBeforeDisconnected() {
            GWT.log("comet.beforeDisconnected");

            eventBus.fireEvent(new CometBeforeDisconnectedEvent());
        }

        @Override
        public void onDisconnected() {
            GWT.log("comet.disconnected");

            if (connected) {
                connected = false;
                eventBus.fireEvent(new CometDisconnectedEvent());
            }
        }

        @Override
        public void onError(Throwable exception, boolean connected) {
            int statuscode = -1;
            if (exception instanceof StatusCodeException) {
                statuscode = ((StatusCodeException) exception).getStatusCode();
            }
            GWT.log("comet.error [connected=" + connected + "] (" + statuscode + ")", exception);

            eventBus.fireEvent(new CometErrorEvent(connected));

            if (connected == false && CometListener.this.connected) {
                CometListener.this.connected = false;
                eventBus.fireEvent(new CometDisconnectedEvent());
            }
        }

        @Override
        public void onHeartbeat() {
            GWT.log("comet.heartbeat [" + client.getConnectionID() + "]");

            eventBus.fireEvent(new CometHeartbeatEvent());

        }

        @Override
        public void onRefresh() {
            GWT.log("comet.refresh [" + client.getConnectionID() + "]");
        }

        @Override
        public void onAfterRefresh() {
            GWT.log("comet.afterRefresh [" + client.getConnectionID() + "]");
        }

        @Override
        public void onMessage(List<?> messages) {

            StringBuilder result = new StringBuilder();
            for (Object obj : messages) {
                result.append(obj.toString()).append("<br/>");
            }
            GWT.log("comet.message [" + client.getConnectionID() + "] " + result.toString());
            GWT.log("[" + client.getConnectionID() + "] Received " + messages.size() + " messages");

            for (Object message : messages) {
                if (message instanceof String) {
                    try {
                        String messageString = (String) message;
                        messageString = messageString.replaceAll("\\\n", "\\n");
                        Message bean = messageReader.read(messageString);

                        String code = bean.code;

                        Sendable object = bean.body;

                        eventBus.fireEvent(new CometMessageEvent(code, object));
                    } catch (Exception ex) {
                        GWT.log("Couldn't parse incoming data!", ex);
                    }
                }
            }
        }
    }

    @SuppressWarnings("unused")
    public void initialize() {
        if (initialized)
            return;

        if (!WebSocketCometTransport.hasWebSocketSupport() && ENFORCE_WEBSOCKET) {
            Window.alert(messages.webSocketSupportMissingAlert());
            return;
        }

        MyCometListener cometListener = new MyCometListener();

        AtmosphereGWTSerializer serializer = GWT.create(StringSerializer.class);
        // set a small length parameter to force refreshes
        // normally you should remove the length parameter
        String url = Akanoo.getAtmosphereUrl();

        client = new AtmosphereClient(url, serializer, cometListener, SUPPORT_WEBSOCKET);
        client.start();

        initialized = true;
    }

    public boolean isConnected() {
        return connected;
    }

    public void sendInitializer() {
        send(MessageConstants.initialize.toString(), null);
    }

    public void send(String code, Sendable sendable) {
        String bodyValueString = sendableConverter.serialize(sendable);

        StringBuilder sb = new StringBuilder();

        sb.append("{");
        sb.append("\"code\":\"");
        sb.append(code);
        sb.append("\"");
        sb.append(",");
        sb.append("\"body\":");
        sb.append(bodyValueString);
        sb.append("}");

        String payload = sb.toString();

        GWT.log("comet.post [" + client.getConnectionID() + "] " + payload);
        client.post(payload);
    }
}