Java基础知识强化之网络编程笔记24：Android网络通信之 AndroidAsync（基于nio的异步通信库）
1. AndroidAsync
AndroidAsync 是一个基于nio的异步socket ，http（客户端服务器端），websocket，socket.io库，AndroidAsync 是一个底层的网络协议库，如果你想要一个容易使用，高级的，http请求库，请使用Ion（它是基于AndroidAsync 的），正常来说开发者更倾向于使用 Ion。
如果你需要一个未被封装的Android的raw Socket， HTTP client/server, WebSocket, and Socket.IO， AndroidAsync 正适合你。
2. AndroidAsync 的特性
- 基于NIO，一个线程，回调驱动，高效
- 所有的操作返回一个Future，而且可以取消
- All operations return a Future that can be cancelled
- Socket client + socket server
- HTTP client + server
- WebSocket client + server
- Socket.IO 客户端
3. AndroidAsync 的下载
<dependency>
<groupId>com.koushikdutta.async</groupId>
<artifactId>androidasync</artifactId>
<version>(insert latest version)</version>
</dependency>
4. AndroidAsync 的使用
（1）下载一个字符串
1 // url is the URL to download. 2 AsyncHttpClient.getDefaultInstance().getString(url, new AsyncHttpClient.StringCallback() { 3 // Callback is invoked with any exceptions/errors, and the result, if available. 4 @Override 5 public void onCompleted(Exception e, AsyncHttpResponse response, String result) { 6 if (e != null) { 7 e.printStackTrace(); 8 return; 9 } 10 System.out.println("I got a string: " + result); 11 } 12 });
（2）下载一个Json
1 // url is the URL to download. 2 AsyncHttpClient.getDefaultInstance().getJSONObject(url, new AsyncHttpClient.JSONObjectCallback() { 3 // Callback is invoked with any exceptions/errors, and the result, if available. 4 @Override 5 public void onCompleted(Exception e, AsyncHttpResponse response, JSONObject result) { 6 if (e != null) { 7 e.printStackTrace(); 8 return; 9 } 10 System.out.println("I got a JSONObject: " + result); 11 } 12 });
（3）下载一个文件
1 AsyncHttpClient.getDefaultInstance().getFile(url, filename, new AsyncHttpClient.FileCallback() { 2 @Override 3 public void onCompleted(Exception e, AsyncHttpResponse response, File result) { 4 if (e != null) { 5 e.printStackTrace(); 6 return; 7 } 8 System.out.println("my file is available at: " + result.getAbsolutePath()); 9 } 10 });
（4）支持缓存
1 // arguments are the http client, the directory to store cache files, and the size of the cache in bytes 2 ResponseCacheMiddleware.addCache(AsyncHttpClient.getDefaultInstance(), 3 getFileStreamPath("asynccache"), 4 1024 * 1024 * 10);
（5）创建一个Socket
1 AsyncHttpClient.getDefaultInstance().websocket(get, "my-protocol", new WebSocketConnectCallback() { 2 @Override 3 public void onCompleted(Exception ex, WebSocket webSocket) { 4 if (ex != null) { 5 ex.printStackTrace(); 6 return; 7 } 8 webSocket.send("a string"); 9 webSocket.send(new byte[10]); 10 webSocket.setStringCallback(new StringCallback() { 11 public void onStringAvailable(String s) { 12 System.out.println("I got a string: " + s); 13 } 14 }); 15 webSocket.setDataCallback(new DataCallback() { 16 public void onDataAvailable(ByteBufferList byteBufferList) { 17 System.out.println("I got some bytes!"); 18 // note that this data has been read 19 byteBufferList.recycle(); 20 } 21 }); 22 } 23 });
（6）支持socket io
1 SocketIOClient.connect(AsyncHttpClient.getDefaultInstance(), "http://192.168.1.2:3000", new ConnectCallback() { 2 @Override 3 public void onConnectCompleted(Exception ex, SocketIOClient client) { 4 if (ex != null) { 5 ex.printStackTrace(); 6 return; 7 } 8 client.setStringCallback(new StringCallback() { 9 @Override 10 public void onString(String string) { 11 System.out.println(string); 12 } 13 }); 14 client.on("someEvent", new EventCallback() { 15 @Override 16 public void onEvent(JSONArray argument, Acknowledge acknowledge) { 17 System.out.println("args: " + arguments.toString()); 18 } 19 }); 20 client.setJSONCallback(new JSONCallback() { 21 @Override 22 public void onJSON(JSONObject json) { 23 System.out.println("json: " + json.toString()); 24 } 25 }); 26 } 27 });
（7）提交表单
1 AsyncHttpPost post = new AsyncHttpPost("http://myservercom/postform.html"); 2 MultipartFormDataBody body = new MultipartFormDataBody(); 3 body.addFilePart("my-file", new File("/path/to/file.txt"); 4 body.addStringPart("foo", "bar"); 5 post.setBody(body); 6 AsyncHttpClient.getDefaultInstance().execute(post, new StringCallback() { 7 @Override 8 public void onCompleted(Exception e, AsyncHttpResponse source, String result) { 9 if (e != null) { 10 ex.printStackTrace(); 11 return; 12 } 13 System.out.println("Server says: " + result); 14 } 15 });
（8）创建一个http server
1 AsyncHttpServer server = new AsyncHttpServer(); 2 List<WebSocket> _sockets = new ArrayList<WebSocket>(); 3 server.get("/", new HttpServerRequestCallback() { 4 @Override 5 public void onRequest(AsyncHttpServerRequest request, AsyncHttpServerResponse response) { 6 response.send("Hello!!!"); 7 } 8 }); 9 // listen on port 5000 10 server.listen(5000); 11 // browsing http://localhost:5000 will return Hello!!!
接着，创建一个websocket server
1 server.websocket("/live", new WebSocketRequestCallback() { 2 @Override 3 public void onConnected(final WebSocket webSocket, AsyncHttpServerRequest request) { 4 _sockets.add(webSocket); 5 //Use this to clean up any references to your websocket 6 websocket.setClosedCallback(new CompletedCallback() { 7 @Override 8 public void onCompleted(Exception ex) { 9 try { 10 if (ex != null) 11 Log.e("WebSocket", "Error"); 12 } finally { 13 _sockets.remove(webSocket); 14 } 15 } 16 }); 17 webSocket.setStringCallback(new StringCallback() { 18 @Override 19 public void onStringAvailable(String s) { 20 if ("Hello Server".equals(s)) 21 webSocket.send("Welcome Client!"); 22 } 23 }); 24 } 25 }); 26 //..Sometime later, broadcast! 27 for (WebSocket socket : _sockets) 28 socket.send("Fireball!");
（9）支持Future
1 Future<String> string = client.getString("http://foo.com/hello.txt"); 2 // this will block, and may also throw if there was an error! 3 String value = string.get();
5. AndroidAsync的下载
开源地址：https://github.com/koush/AndroidAsync