String appKey = "key";
String appSecret = "secret";

//init appKey appSecret
//NOTE init is  slow ,It will be cost 5s
DotEngine dotEngine = new DotEngine(appKey, appSecret);

//set connect timeout  default 10s
dotEngine.setConnectTimeout(2000);

//set read timeout  default 10s
dotEngine.setReadTimeout(2000);

//enable log
dotEngine.enableLog();

String token = null;
try {
    //set  room user expireTime
    token = dotEngine.createToken("room", "user", 24 * 36000);

} catch (GenerateTokenException e) {
    //create token   failure
    e.printStackTrace();
}

//get result token  ; if failure return  null
System.out.println(token);