Java tutorial
/* * Copyright 2014 The WebRTC Project Authors. All rights reserved. * * Use of this source code is governed by a BSD-style license * that can be found in the LICENSE file in the root of the source * tree. An additional intellectual property rights grant can be found * in the file PATENTS. All contributing project authors may * be found in the AUTHORS file in the root of the source tree. */ package com.ardnezar.lookapp; import android.util.Log; import com.ardnezar.lookapp.util.AsyncHttpURLConnection; import com.ardnezar.lookapp.util.LooperExecutor; import org.json.JSONException; import org.json.JSONObject; import java.net.URI; import java.net.URISyntaxException; import java.util.LinkedList; import de.tavendo.autobahn.WebSocket.WebSocketConnectionObserver; import de.tavendo.autobahn.WebSocketConnection; import de.tavendo.autobahn.WebSocketException; /** * WebSocket client implementation. * * <p>All public methods should be called from a looper executor thread * passed in a constructor, otherwise exception will be thrown. * All events are dispatched on the same thread. */ public class WebSocketChannelClient { private static final String TAG = "WSChannelRTCClient"; private static final int CLOSE_TIMEOUT = 1000; private final WebSocketChannelEvents events; private final LooperExecutor executor; private WebSocketConnection ws; private WebSocketObserver wsObserver; private String wsServerUrl; private String postServerUrl; private String roomID; private String clientID; private WebSocketConnectionState state; private final Object closeEventLock = new Object(); private boolean closeEvent; // WebSocket send queue. Messages are added to the queue when WebSocket // client is not registered and are consumed in register() call. private final LinkedList<String> wsSendQueue; /** * Possible WebSocket connection states. */ public enum WebSocketConnectionState { NEW, CONNECTED, REGISTERED, CLOSED, ERROR }; /** * Callback interface for messages delivered on WebSocket. * All events are dispatched from a looper executor thread. */ public interface WebSocketChannelEvents { public void onWebSocketMessage(final String message); public void onWebSocketClose(); public void onWebSocketError(final String description); } public WebSocketChannelClient(LooperExecutor executor, WebSocketChannelEvents events) { this.executor = executor; this.events = events; roomID = null; clientID = null; wsSendQueue = new LinkedList<String>(); state = WebSocketConnectionState.NEW; } public WebSocketConnectionState getState() { return state; } public void connect(final String wsUrl, final String postUrl) { checkIfCalledOnValidThread(); if (state != WebSocketConnectionState.NEW) { Log.e(TAG, "WebSocket is already connected."); return; } wsServerUrl = wsUrl; postServerUrl = postUrl; closeEvent = false; Log.d(TAG, "Connecting WebSocket to: " + wsUrl + ". Post URL: " + postUrl); ws = new WebSocketConnection(); wsObserver = new WebSocketObserver(); try { ws.connect(new URI(wsServerUrl), wsObserver); } catch (URISyntaxException e) { reportError("URI error: " + e.getMessage()); } catch (WebSocketException e) { reportError("WebSocket connection error: " + e.getMessage()); } } public void register(final String roomID, final String clientID) { checkIfCalledOnValidThread(); this.roomID = roomID; this.clientID = clientID; if (state != WebSocketConnectionState.CONNECTED) { Log.w(TAG, "WebSocket register() in state " + state); return; } Log.d(TAG, "Registering WebSocket for room " + roomID + ". CLientID: " + clientID); JSONObject json = new JSONObject(); try { json.put("cmd", "register"); json.put("roomid", roomID); json.put("clientid", clientID); Log.d(TAG, "C->WSS: " + json.toString()); ws.sendTextMessage(json.toString()); state = WebSocketConnectionState.REGISTERED; // Send any previously accumulated messages. for (String sendMessage : wsSendQueue) { send(sendMessage); } wsSendQueue.clear(); } catch (JSONException e) { reportError("WebSocket register JSON error: " + e.getMessage()); } } public void send(String message) { checkIfCalledOnValidThread(); switch (state) { case NEW: case CONNECTED: // Store outgoing messages and send them after websocket client // is registered. Log.d(TAG, "WS ACC: " + message); wsSendQueue.add(message); return; case ERROR: case CLOSED: Log.e(TAG, "WebSocket send() in error or closed state : " + message); return; case REGISTERED: JSONObject json = new JSONObject(); try { json.put("cmd", "send"); json.put("msg", message); message = json.toString(); Log.d(TAG, "C->WSS: " + message); ws.sendTextMessage(message); } catch (JSONException e) { reportError("WebSocket send JSON error: " + e.getMessage()); } break; } return; } // This call can be used to send WebSocket messages before WebSocket // connection is opened. public void post(String message) { checkIfCalledOnValidThread(); sendWSSMessage("POST", message); } public void disconnect(boolean waitForComplete) { checkIfCalledOnValidThread(); Log.d(TAG, "Disonnect WebSocket. State: " + state); if (state == WebSocketConnectionState.REGISTERED) { // Send "bye" to WebSocket server. send("{\"type\": \"bye\"}"); state = WebSocketConnectionState.CONNECTED; // Send http DELETE to http WebSocket server. sendWSSMessage("DELETE", ""); } // Close WebSocket in CONNECTED or ERROR states only. if (state == WebSocketConnectionState.CONNECTED || state == WebSocketConnectionState.ERROR) { ws.disconnect(); state = WebSocketConnectionState.CLOSED; // Wait for websocket close event to prevent websocket library from // sending any pending messages to deleted looper thread. if (waitForComplete) { synchronized (closeEventLock) { while (!closeEvent) { try { closeEventLock.wait(CLOSE_TIMEOUT); break; } catch (InterruptedException e) { Log.e(TAG, "Wait error: " + e.toString()); } } } } } Log.d(TAG, "Disonnecting WebSocket done."); } private void reportError(final String errorMessage) { Log.e(TAG, errorMessage); executor.execute(new Runnable() { @Override public void run() { if (state != WebSocketConnectionState.ERROR) { state = WebSocketConnectionState.ERROR; events.onWebSocketError(errorMessage); } } }); } // Asynchronously send POST/DELETE to WebSocket server. private void sendWSSMessage(final String method, final String message) { String postUrl = postServerUrl + "/" + roomID + "/" + clientID; Log.d(TAG, "WS " + method + " : " + postUrl + " : " + message); AsyncHttpURLConnection httpConnection = new AsyncHttpURLConnection(method, postUrl, message, new AsyncHttpURLConnection.AsyncHttpEvents() { @Override public void onHttpError(String errorMessage) { reportError("WS " + method + " error: " + errorMessage); } @Override public void onHttpComplete(String response) { } }); httpConnection.send(); } // Helper method for debugging purposes. Ensures that WebSocket method is // called on a looper thread. private void checkIfCalledOnValidThread() { if (!executor.checkOnLooperThread()) { throw new IllegalStateException("WebSocket method is not called on valid thread"); } } private class WebSocketObserver implements WebSocketConnectionObserver { @Override public void onOpen() { Log.d(TAG, "WebSocket connection opened to: " + wsServerUrl); executor.execute(new Runnable() { @Override public void run() { state = WebSocketConnectionState.CONNECTED; // Check if we have pending register request. if (roomID != null && clientID != null) { register(roomID, clientID); } } }); } @Override public void onClose(WebSocketCloseNotification code, String reason) { Log.d(TAG, "WebSocket connection closed. Code: " + code + ". Reason: " + reason + ". State: " + state); synchronized (closeEventLock) { closeEvent = true; closeEventLock.notify(); } executor.execute(new Runnable() { @Override public void run() { if (state != WebSocketConnectionState.CLOSED) { state = WebSocketConnectionState.CLOSED; events.onWebSocketClose(); } } }); } @Override public void onTextMessage(String payload) { Log.d(TAG, "WSS->C: " + payload); final String message = payload; executor.execute(new Runnable() { @Override public void run() { if (state == WebSocketConnectionState.CONNECTED || state == WebSocketConnectionState.REGISTERED) { events.onWebSocketMessage(message); } } }); } @Override public void onRawTextMessage(byte[] payload) { } @Override public void onBinaryMessage(byte[] payload) { } } }