WebSocket handshake: Unexpected response code: 404

问题

Am writing my first websocket program and am getting "WebSocket handshake: Unexpected response code: 404", error while loading the webpage.

I am using JDK 1.7 and jboss 8 (wildfly8.0).

Could anyone please assist?

window.onload = init;
var socket = new WebSocket("ws://localhost:8080/WebsocketHome/actions"); 
socket.onmessage = onMessage;

and head in html

<head> 
 <title></title>
 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <script src="websocket.js" type="text/javascript"></script> 
 <link rel="stylesheet" type="text/css" href="style.css"> 
</head>

回答1:

Thank you guys for your suggestion, I found the answer.

The code I copied is from http://www.oracle.com/webfolder/technetwork/tutorials/obe/java/HomeWebsocket/WebsocketHome.html site.

The problem was the url as mentioned in the js file and the project name they are proposing is WebsocketHome. I had changed the project name to Websocket thus my url should be ws://localhost:8080/Websocket/actions.

Thanks for your support.

回答2:

Actually, the problem here is case-sensitivity in the URLs. You did not need to change the project name. Just changing the Websocket URL in JavaScript file to

ws://localhost:8080/WebSocketHome/actions

(with capital S, as in the project name) would have solved the problem. In your case, changing both of them removed the case inconsistency, so it worked.

回答3:

It's because of the issue of /info=34424 - with 404 error - that I had to abandon using the xml approach suggested at other places. I have Spring 4.2 in my project and many SockJS Stomp implementations usually work well with Spring Boot implementations. This implementation from Baeldung worked(for me without changing from Spring 4.2 to 5). After Using the dependencies mentioned in his blog, it still gave me ClassNotFoundError. I added the below dependency to fix it.

<dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-core</artifactId>
        <version>4.2.3.RELEASE</version>
    </dependency>

Baeldung's implementation curiously does not make any such calls

flow/websocket/add/info?t=1540813753999

What it does (on send and receive) is below. I am only pasting it in case people well-versed with these libraries can further add insights on this forum.

 >>> SEND
destination:/app/chat
content-length:38

{"from":"nicholas","text":"try again"}

<<< MESSAGE
destination:/topic/messages
content-type:application/json;charset=UTF-8
subscription:sub-0
message-id:m3p096zk-11
content-length:53

{"from":"nicholas","text":"try again","time":"13:46"}

来源：https://stackoverflow.com/questions/29455986/websocket-handshake-unexpected-response-code-404

标签

javascript

websocket

wildfly-8