update README

README.md

@@ -1,4 +1,29 @@
-engine.io-client.java
-=====================
+# Engine.IO-client.java
 [![Build Status](https://travis-ci.org/nkzawa/engine.io-client.java.png?branch=master)](https://travis-ci.org/nkzawa/engine.io-client.java)
-Engine.IO Client Library for Java
+
+This is the Engine.IO Client Library for Java, which is simply ported from the [client](https://github.com/LearnBoost/engine.io-client) for JavaScript.
+
+## Hello World
+Engine.IO-client.java has the similar api with the client for js. You can use `Socket` to connect as follows:
+
+```java
+Socket socket = new Socket("ws://localhost") {
+  @Override
+  public void onopen() {}
+
+  @Override
+  public void onmessage(String data) {}
+
+  @Override
+  public void onclose() {}
+};
+socket.open();
+```
+
+## Features
+This library supports all of the features the JS client does, except the Flash transport, including events, options and upgrage.
+
+## License
+
+MIT
+