AndroidAsync is a low level network protocol library. If you are looking for an easy to use, higher level, Android aware, http request library, check out Ion (it is built on top of AndroidAsync). The typical Android app developer would probably be more interested in Ion.
But if you‘re looking for a raw Socket, HTTP client/server, WebSocket, and Socket.IO library for Android, AndroidAsync is it.
Features
Based on NIO. One thread, driven by callbacks. Highly efficient.
All operations return a Future that can be cancelled
Socket client + socket server
HTTP client + server
WebSocket client + server
Socket.IO client
Download
Download the latest JAR or grab via Maven:
<dependency> <groupId>com.koushikdutta.async</groupId> <artifactId>androidasync</artifactId> <version>(insert latest version)</version></dependency>
Download a url to a String
// url is the URL to download.AsyncHttpClient.getDefaultInstance().getString(url, new AsyncHttpClient.StringCallback() {
// Callback is invoked with any exceptions/errors, and the result, if available.
@Override
public void onCompleted(Exception e, AsyncHttpResponse response, String result) {
if (e != null) {
e.printStackTrace();
return;
}
System.out.println("I got a string: " + result);
}});
Download JSON from a url
// url is the URL to download.AsyncHttpClient.getDefaultInstance().getJSONObject(url, new AsyncHttpClient.JSONObjectCallback() {
// Callback is invoked with any exceptions/errors, and the result, if available.
@Override
public void onCompleted(Exception e, AsyncHttpResponse response, JSONObject result) {
if (e != null) {
e.printStackTrace();
return;
}
System.out.println("I got a JSONObject: " + result);
}});
Or for JSONArrays...
// url is the URL to download.AsyncHttpClient.getDefaultInstance().getJSONArray(url, new AsyncHttpClient.JSONArrayCallback() {
// Callback is invoked with any exceptions/errors, and the result, if available.
@Override
public void onCompleted(Exception e, AsyncHttpResponse response, JSONArray result) {
if (e != null) {
e.printStackTrace();
return;
}
System.out.println("I got a JSONArray: " + result);
}});
Download a url to a file
AsyncHttpClient.getDefaultInstance().getFile(url, filename, new AsyncHttpClient.FileCallback() {
@Override
public void onCompleted(Exception e, AsyncHttpResponse response, File result) {
if (e != null) {
e.printStackTrace();
return;
}
System.out.println("my file is available at: " + result.getAbsolutePath());
}});
Caching is supported too
// arguments are the http client, the directory to store cache files, and the size of the cache in bytesResponseCacheMiddleware.addCache(AsyncHttpClient.getDefaultInstance(),
getFileStreamPath("asynccache"),
1024 * 1024 * 10);
Can also create web sockets:
AsyncHttpClient.getDefaultInstance().websocket(get, "my-protocol", new WebSocketConnectCallback() {
@Override
public void onCompleted(Exception ex, WebSocket webSocket) {
if (ex != null) {
ex.printStackTrace();
return;
}
webSocket.send("a string");
webSocket.send(new byte[10]);
webSocket.setStringCallback(new StringCallback() {
public void onStringAvailable(String s) {
System.out.println("I got a string: " + s);
}
});
webSocket.setDataCallback(new DataCallback() {
public void onDataAvailable(ByteBufferList byteBufferList) {
System.out.println("I got some bytes!");
// note that this data has been read
byteBufferList.recycle();
}
});
}});
AndroidAsync also supports socket.io
SocketIOClient.connect(AsyncHttpClient.getDefaultInstance(), "http://192.168.1.2:3000", new ConnectCallback() {
@Override
public void onConnectCompleted(Exception ex, SocketIOClient client) {
if (ex != null) {
ex.printStackTrace();
return;
}
client.setStringCallback(new StringCallback() {
@Override
public void onString(String string) {
System.out.println(string);
}
});
client.on("someEvent", new EventCallback() {
@Override
public void onEvent(JSONArray argument, Acknowledge acknowledge) {
System.out.println("args: " + arguments.toString());
}
});
client.setJSONCallback(new JSONCallback() {
@Override
public void onJSON(JSONObject json) {
System.out.println("json: " + json.toString());
}
});
}});
Need to do multipart/form-data uploads? That works too.
AsyncHttpPost post = new AsyncHttpPost("http://myservercom/postform.html");MultipartFormDataBody body = new MultipartFormDataBody();body.addFilePart("my-file", new File("/path/to/file.txt");body.addStringPart("foo", "bar");post.setBody(body);AsyncHttpClient.getDefaultInstance().execute(post, new StringCallback() {
@Override
public void onCompleted(Exception e, AsyncHttpResponse source, String result) {
if (e != null) {
ex.printStackTrace();
return;
}
System.out.println("Server says: " + result);
}});
AndroidAsync also let‘s you create simple HTTP servers:
AsyncHttpServer server = new AsyncHttpServer();List<WebSocket> _sockets = new ArrayList<WebSocket>();server.get("/", new HttpServerRequestCallback() {
@Override
public void onRequest(AsyncHttpServerRequest request, AsyncHttpServerResponse response) {
response.send("Hello!!!");
}});// listen on port 5000server.listen(5000);// browsing http://localhost:5000 will return Hello!!!
And WebSocket Servers:
server.websocket("/live", new WebSocketRequestCallback() {
@Override
public void onConnected(final WebSocket webSocket, RequestHeaders headers) {
_sockets.add(webSocket);
//Use this to clean up any references to your websocket
websocket.setClosedCallback(new CompletedCallback() {
@Override
public void onCompleted(Exception ex) {
try {
if (ex != null)
Log.e("WebSocket", "Error");
} finally {
_sockets.remove(webSocket);
}
}
});
webSocket.setStringCallback(new StringCallback() {
@Override
public void onStringAvailable(String s) {
if ("Hello Server".equals(s))
webSocket.send("Welcome Client!");
}
});
}});//..Sometime later, broadcast!for (WebSocket socket : _sockets)
socket.send("Fireball!");
Futures
All the API calls return Futures.
Future<String> string = client.getString("http://foo.com/hello.txt");// this will block, and may also throw if there was an error!String value = string.get();
Futures can also have callbacks...
Future<String> string = client.getString("http://foo.com/hello.txt");string.setCallback(new FutureCallback<String>() {
@Override
public void onCompleted(Exception e, String result) {
System.out.println(result);
}});
For brevity...
client.getString("http://foo.com/hello.txt").setCallback(new FutureCallback<String>() {
@Override
public void onCompleted(Exception e, String result) {
System.out.println(result);
}});