anchor.diff:  
   InputElement passwordInput,usernameInput;
   ButtonElement loginButton;
  -  
  +
   var wsClient = new WebSocket('ws://ec2-52-68-77-61.ap-northeast-1.compute.amazonaws.com:3000');
   
  +/// Class of websocket message 
   class webSocketMessage {
   
   	String type;
   	Map value;
   
   	@override
  -	String toString(){
  -		Map map = new Map();
  -		map["type"] = type;
  -		map["value"] = value;
  -		return JSON.encode(map);
  -	}
  +		String toString(){
  +			Map map = new Map();
  +			map["type"] = type;
  +			map["value"] = value;
  +			return JSON.encode(map);
  +		}
   	webSocketMessage(this.type,this.value);
   
   	factory webSocketMessage.fromJsonString(String message_str){
  
positive.code: 		case 'result':
  			break;
  		default:
    			querySelector("#message_text").text = "Error";
  			break;
  	}
  }
  
negative.code: }
  
  void main() {
  	//要素の初期化
  	usernameInput = querySelector('#login-username');
  	passwordInput = querySelector('#login-pass');
  	loginButton = querySelector('#login-button');
  	changeDisplayMessage("Hello!");
  	loginButton.onClick.listen(loginRequest);
  
  	wsClient.onMessage.listen(reciveWebsocketData);
  }
  
  /// Change Message of #message-text
  void changeDisplayMessage(String text){
  	querySelector("#message-text").text = text;
  }
  
  ///Send Login Request 
  void loginRequest(Event e){
  	var userName = usernameInput.value;
  	var password = passwordInput.value;
  	if(userName != "" && password != ""){
  		Map value = new Map();
  		value["username"] = userName;
  		value["password"] = password;
  		var send_message = new webSocketMessage("webAuth",value);
  		//Send Data on Web Socket 
  		if(wsClient != null && wsClient.readyState == WebSocket.OPEN){
  			wsClient.send(send_message.toString());
  			changeDisplayMessage("Send Message!");
  		} else {
  			changeDisplayMessage("Can't send...");
  		}
  	} else {
  		changeDisplayMessage("Don't input password or username");
  	}
  			querySelector("#message_text").text = "Error";
  }
  
  ///Check login message ( type : webauth )
  void checkLogin(webSocketMessage message){
  	// value.result - 0:succeed Others: fail
  	if(message.value["result"] == 0){
  		//TODO
  		changeDisplayMessage("Succeeded in longing!");
  	} else {
  		changeDisplayMessage("Failed to Login :" + message.value["error"]);
  	}
  
  }
  
  /// Check Message
  