I am learning spring 4 websocket and i will be much thankful if anyone can guide me to learn spring 4 websocket step by step or can suggest some book where i can find step by step practical approach on the said subject.
But before that a little help needed here with this snippet that i am trying to execute on eclipse using tomcat 8 .
index.html
<!DOCTYPE html>
<html>
<head>
<title>Hello WebSocket</title>
<script src="https://raw.githubusercontent.com/spring-guides/gs-messaging-stomp-websocket/master/complete/src/main/resources/static/sockjs-0.3.4.js"></script>
<script src="https://raw.githubusercontent.com/spring-guides/gs-messaging-stomp-websocket/master/complete/src/main/resources/static/stomp.js"></script>
<script type="text/javascript">
var stompClient = null;
function setConnected(connected) {
document.getElementById('connect').disabled = connected;
document.getElementById('disconnect').disabled = !connected;
document.getElementById('conversationDiv').style.visibility = connected ? 'visible' : 'hidden';
document.getElementById('response').innerHTML = '';
}
function connect() {
var socket = new SockJS("<c:url value='/hello'/>");
stompClient = Stomp.over(socket);
stompClient.connect('', '', function(frame) {
setConnected(true);
console.log('Connected: ' + frame);
stompClient.subscribe("<c:url value='/topic/greetings'/>", function(greeting){
showGreeting(JSON.parse(greeting.body).content);
});
});
}
function disconnect() {
stompClient.disconnect();
setConnected(false);
console.log("Disconnected");
}
function sendName() {
var name = document.getElementById('name').value;
stompClient.send("<c:url value='/app/hello'/>", {}, JSON.stringify({ 'name': name }));
}
function showGreeting(message) {
var response = document.getElementById('response');
var p = document.createElement('p');
p.style.wordWrap = 'break-word';
p.appendChild(document.createTextNode(message));
response.appendChild(p);
}
</script>
</head>
<body>
<noscript><h2 style="color: #ff0000">Seems your browser doesn't support Javascript! Websocket relies on Javascript being enabled. Please enable
Javascript and reload this page!</h2></noscript>
<div>
<div>
<button id="connect" onclick="connect();">Connect</button>
<button id="disconnect" disabled="disabled" onclick="disconnect();">Disconnect</button>
</div>
<div id="conversationDiv">
<label>What is your name?</label><input type="text" id="name" />
<button id="sendName" onclick="sendName();">Send</button>
<p id="response"></p>
</div>
</div>
</body>
</html>
Greeting.java
public class Greeting {
private String content;
public Greeting(String content) {
this.content = content;
}
public String getContent() {
return content;
}
}
GreetingController.java
import org.springframework.messaging.handler.annotation.MessageMapping;
import org.springframework.messaging.handler.annotation.SendTo;
import org.springframework.stereotype.Controller;
@Controller
public class GreetingController {
@MessageMapping("/hello")
@SendTo("/topic/greetings")
public Greeting greeting(HelloMessage message) throws Exception {
Thread.sleep(3000); // simulated delay
System.out.println(message.getName());
return new Greeting("Hello, " + message.getName() + "!");
}
}
HelloMessage.java
package com.iiw.controller.relationship;
public class HelloMessage {
private String name;
public String getName() {
return name;
}
}
WebsocketConfig.xml
<websocket:message-broker application-destination-prefix="/app">
<websocket:stomp-endpoint path="/hello">
<websocket:sockjs/>
</websocket:stomp-endpoint>
<websocket:simple-broker prefix="/topic"/>
</websocket:message-broker>
web.xml
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
id="WebApp_ID"
version="3.0">
<display-name>CRUDWebAppMavenized</display-name>
<listener>
<listener-class>
org.springframework.web.context.ContextLoaderListener
</listener-class>
</listener>
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/applicationContext.xml , /WEB-INF/SecurityContext.xml , /WEB-INF/WebSocketConfig.xml</param-value>
</context-param>
<listener>
<listener-class>org.springframework.web.util.Log4jConfigListener</listener-class>
</listener>
<context-param>
<param-name>log4jConfigLocation</param-name>
<param-value>classpath:log4j.xml</param-value>
</context-param>
<servlet>
<servlet-name>spring</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>spring</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
<filter>
<filter-name>springSecurityFilterChain</filter-name>
<filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
</filter>
<filter-mapping>
<filter-name>springSecurityFilterChain</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>
The Problem is everytime i am running this code, this is giving nothing
Change connect function
from:
function connect() {
var socket = new SockJS("<c:url value='/hello'/>");
stompClient = Stomp.over(socket);
stompClient.connect('', '', function(frame) {
setConnected(true);
console.log('Connected: ' + frame);
stompClient.subscribe("<c:url value='/topic/greetings'/>", function(greeting){
showGreeting(JSON.parse(greeting.body).content);
});
});
}
To:
function connect() {
var socket = new SockJS("<c:url value='/hello'/>");
stompClient = Stomp.over(socket);
stompClient.connect('', '', function(frame) {
setConnected(true);
console.log('Connected: ' + frame);
stompClient.subscribe('/topic/greetings', function(greeting){
showGreeting(JSON.parse(greeting.body).content);
});
});
}
and similarly for sendName()
From:
function sendName() {
var name = document.getElementById('name').value;
stompClient.send("<c:url value='/app/hello'/>", {}, JSON.stringify({ 'name': name }));
}
To:
function sendName() {
var name = document.getElementById('name').value;
stompClient.send('/app/hello', {}, JSON.stringify({ 'name': name }));
}
来源：https://stackoverflow.com/questions/29211425/spring-4-websocket-nothing-happens