wAsync: A WebSockets/HTTP Client Library for Asynchronous Communication
wAsync is a Java based library allowing asynchronous communication with any WebServer supporting the WebSocket or Http Protocol. wAsync can be used with Node.js, Android, Atmosphere or any WebSocket Framework. To get started, read this super simple Tutorial or read the FAQ
You can browse the javadoc or browse our samples.
You can download the jar or use Maven
<dependency>
<groupId>org.atmosphere</groupId>
<artifactId>wasync</artifactId>
<version>2.1.7</version>
</dependency>
As simple as
Client client = ClientFactory.getDefault().newClient();
RequestBuilder request = client.newRequestBuilder()
.method(Request.METHOD.GET)
.uri("http://async-io.org")
.encoder(new Encoder<String, Reader>() { // Stream the request body
@Override
public Reader encode(String s) {
return new StringReader(s);
}
})
.decoder(new Decoder<String, Reader>() {
@Override
public Reader decode(Event type, String s) {
return new StringReader(s);
}
})
.transport(Request.TRANSPORT.WEBSOCKET) // Try WebSocket
.transport(Request.TRANSPORT.LONG_POLLING); // Fallback to Long-Polling
Socket socket = client.create();
socket.on(new Function<Reader>() {
@Override
public void on(Reader r) {
// Read the response
}
}).on(new Function<IOException>() {
@Override
public void on(IOException ioe) {
// Some IOException occurred
}
}).open(request.build())
.fire("echo")
.fire("bong");
Life cycle of the underlying Socket can easily be implemented as well
Socket socket = client.create();
socket.on(Event.CLOSE.name(), new Function<String>() {
@Override
public void on(String t) {
}
}).on(Event.REOPENED.name(), new Function<String>() {
@Override
public void on(String t) {
}
}).on(new Function<IOException>() {
@Override
public void on(IOException ioe) {
ioe.printStackTrace();
}
}).on(Event.OPEN.name(), new Function<String>() {
@Override
public void on(String t) {
}
}).open(request.build());
You can also use the specialized clients. For example, to transparently enable Atmosphere's Protocol
AtmosphereClient client = ClientFactory.getDefault().newClient(AtmosphereClient.class);
RequestBuilder request = client.newRequestBuilder()
.method(Request.METHOD.GET)
.uri(targetUrl + "/suspend")
.trackMessageLength(true)
.transport(Request.TRANSPORT.LONG_POLLING);
or if you want to serialize the fire() method call so events are asynchronously sent in the order the fire method is called
SerializedClient client = ClientFactory.getDefault().newClient(SerializedClient.class);
SerializedOptionsBuilder b = client.newOptionsBuilder();
b.serializedFireStage(new DefaultSerializedFireStage());
RequestBuilder request = client.newRequestBuilder()
.method(Request.METHOD.GET)
.uri(targetUrl + "/suspend")
.transport(Request.TRANSPORT.WEBSOCKET);
Socket socket = client.create(b.build());
By default, the FunctionResolver will associate the Decoder's type will be used to invoke the appropriate Function, if defined. For example,
Decoder<String, POJO> d = new Decoder<String, POJO>() {
@Override
public POJO decode(Event type, String s) {
if (type.equals(Event.MESSAGE)) {
return new POJO(s);
} else {
return s;
}
}
}
will be associated to
Function<String> f = new Function<POJO>() {
@Override
public void on(POJO t) {
}
}
You can also implement your own FunctionResolver to associate the Function with Decoder
Socket socket = client.create();
socket.on("myEvent", new Function<Reader>() { ...}
where myEvent could be read from the response's body.
Want to write an Android Client? See