Can't subscribe to server-sent event using Jersey and Tomcat 7

Question

I am deploying Server-Sent-Event resource with jersey 2.41 / Java 7 / tomcat 7.

I am getting error as

Dec 16, 2013 4:04:40 AM org.apache.catalina.core.StandardWrapperValve invoke SEVERE: Servlet.service() for servlet [ServletAdaptor] in context with path [/trackapp] threw exception [java.lang.UnsupportedOperationException: Asynchronous processing not supported on Servlet 2.x container.] with root cause java.lang.UnsupportedOperationException: Asynchronous processing not supported on Servlet 2.x container. at org.glassfish.jersey.servlet.WebComponent$3.suspend(WebComponent.java:123) at org.glassfish.jersey.servlet.internal.ResponseWriter.suspend(ResponseWriter.java:109) at org.glassfish.jersey.server.ServerRuntime$Responder.writeResponse(ServerRuntime.java:619) at org.glassfish.jersey.server.ServerRuntime$Responder.processResponse(ServerRuntime.java:381) at org.glassfish.jersey.server.ServerRuntime$Responder.process(ServerRuntime.java:371) at org.glassfish.jersey.server.ServerRuntime$1.run(ServerRuntime.java:262) at org.glassfish.jersey.internal.Errors$1.call(Errors.java:271) at org.glassfish.jersey.internal.Errors$1.call(Errors.java:267) at org.glassfish.jersey.internal.Errors.process(Errors.java:315) at org.glassfish.jersey.internal.Errors.process(Errors.java:297) at org.glassfish.jersey.internal.Errors.process(Errors.java:267) at org.glassfish.jersey.process.internal.RequestScope.runInScope(RequestScope.java:318) at org.glassfish.jersey.server.ServerRuntime.process(ServerRuntime.java:236) at org.glassfish.jersey.server.ApplicationHandler.handle(ApplicationHandler.java:983) at org.glassfish.jersey.servlet.WebComponent.service(WebComponent.java:361) at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:372) at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:335) at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:218) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:225) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:927) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1001) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:585) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:744)

my Resource

@POST
@Produces(MediaType.APPLICATION_JSON)
@Consumes(MediaType.APPLICATION_JSON)
public String broadcastMessage(String message) {
    OutboundEvent.Builder eventBuilder = new OutboundEvent.Builder();
    OutboundEvent event = eventBuilder.name("message")
        .mediaType(MediaType.TEXT_PLAIN_TYPE)
        .data(String.class, message)
        .build();

    broadcaster.broadcast(event);
    System.out.println("broadcasting listen [" +message+ "]");

    return "Message was '" + message + "' broadcast.";
}

@GET
@Produces(SseFeature.SERVER_SENT_EVENTS)
@Path("/listen")
public EventOutput listenToBroadcast() {
    System.out.println("will listen");
    final EventOutput eventOutput = new EventOutput();
    this.broadcaster.add(eventOutput);
    return eventOutput;
}

web.xml

<?xml version="1.0" encoding="UTF-8"?>

<web-app version="3.0"
         xmlns="http://java.sun.com/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
         metadata-complete="false">
    <servlet>
        <servlet-name>ServletAdaptor</servlet-name>
        <servlet-class>
            org.glassfish.jersey.servlet.ServletContainer
        </servlet-class>
        <init-param>
            <param-name>jersey.config.server.provider.packages</param-name>
            <param-value>net.jigarshah.mse.tracker</param-value>
        </init-param>
        <init-param>
            <param-name>com.sun.jersey.api.json.POJOMappingFeature</param-name>
            <param-value>true</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>ServletAdaptor</servlet-name>
        <url-pattern>/webapi/*</url-pattern>
    </servlet-mapping>
    <session-config>
        <session-timeout>
            30
        </session-timeout>
    </session-config>

</web-app>

client JS

<script>
var url="http://localhost:8080/trackapp/webapi/broadcast/listen";
var source=new EventSource(url);
source.onerror=function(event)
{
console.log("error");
};

source.onmessage=function(event)
  {
    console.log(event.data);

  document.getElementById("result").innerHTML+=event.data + "<br>";
  };
</script>
</head>
<body>
<div id="result">
test
</div>

Answer 1

One possibility is to check the maven dependencies as listed here https://jersey.java.net/documentation/latest/modules-and-dependencies.html

You can also check that through this message from jersey mailing list https://java.net/projects/jersey/lists/users/archive/2013-11/message/63

Hope this helps.

Answer 2

I had the same trouble, my issue was that I used the wrong jersey servlet implementation. Add to replace

<dependency>
  <groupId>org.glassfish.jersey.containers</groupId>
  <artifactId>jersey-container-servlet-core</artifactId>
</dependency>

by (note the missing -core)

<dependency>
  <groupId>org.glassfish.jersey.containers</groupId>
  <artifactId>jersey-container-servlet</artifactId>
</dependency>