在Embedded Jetty 9上的带注释的@WebSocket类中访问HttpSession

时间:2014-12-27 20:27:01

标签: websocket embedded-jetty jetty-9

如何在Jetty 9中的带注释的@WebSocket类中访问HttpSession对象?

我找到了如何使用@ServerEndpoint注释来完成它,就像这里:HttpSession from @ServerEndpoint

使用@WebSocket注释,就像下面的课程一样,我该怎么做?

@WebSocket
public class AuctionWebSocket {

    // NEED TO ACCESS HttpSession OBJECT INSIDE THESE METHODS:

    @OnWebSocketConnect
    public void onConnect(Session session) {
        System.out.println("onConnect...");        
    }

    @OnWebSocketMessage
    public void onMessage(String message) {        
        System.out.println("Message: " + message);
    }    

    @OnWebSocketClose
    public void onClose(int statusCode, String reason) {
        System.out.println("onClose...");        
    }

    @OnWebSocketError
    public void onError(Throwable t) {
        System.out.println("onError...");        
    }    
}

在方法onConnect(Session session)内,我尝试拨打session.getUpgradeRequest().getSession(),并始终返回null

为了便于获取信息,以下是我启动嵌入式Jetty 9的方法:

public class Main {

    public static void main(String[] args) throws Exception {

        String webPort = System.getenv("PORT");
        if (webPort == null || webPort.isEmpty()) {
            webPort = "8080";
        }

        Server server = new Server(Integer.parseInt(webPort));

        ClassList classlist = org.eclipse.jetty.webapp.Configuration.ClassList.setServerDefault(server);
        classlist.addBefore("org.eclipse.jetty.webapp.JettyWebXmlConfiguration",
                "org.eclipse.jetty.annotations.AnnotationConfiguration");

        WebAppContext wac = new WebAppContext();
        String webappDirLocation = "./src/main/webapp/";

        wac.setAttribute("org.eclipse.jetty.server.webapp.ContainerIncludeJarPattern", ".*/classes/.*");
        wac.setDescriptor(webappDirLocation + "/WEB-INF/web.xml");
        wac.setBaseResource(new ResourceCollection(new String[]{webappDirLocation, "./target"}));
        wac.setResourceAlias("/WEB-INF/classes/", "/classes/");
        wac.setContextPath("/");
        wac.setParentLoaderPriority(true);

        /*
         * WebSocket handler.
         */
        WebSocketHandler wsh = new WebSocketHandler() {

            @Override
            public void configure(WebSocketServletFactory wssf) {
                wssf.register(AuctionWebSocket.class);
            }
        };

        ContextHandler wsc = new ContextHandler();
        wsc.setContextPath("/auction-notifications");
        wsc.setHandler(wsh);

        ContextHandlerCollection chc = new ContextHandlerCollection();
        chc.setHandlers(new Handler[]{wac, wsc});

        server.setHandler(chc);

        server.start();
        server.join();
    }

}

如果您需要更多信息,请与我们联系。

任何帮助将不胜感激。

提前致谢。

1 个答案:

答案 0 :(得分:4)

您想要使用WebSocketCreator概念。

首先,您在WebSocketCreator

中配置的WebSocketServletFactory中设置所选的WebSocketServlet
public class MySessionSocketServlet extends WebSocketServlet
{
    @Override
    public void configure(WebSocketServletFactory factory)
    {
        factory.getPolicy().setIdleTimeout(30000);
        factory.setCreator(new MySessionSocketCreator());
    }
}

接下来,您希望在升级过程中抓取HttpSession并将其传递到您正在创建的WebSocket对象中。

public class MySessionSocketCreator implements WebSocketCreator
{
    @Override
    public Object createWebSocket(ServletUpgradeRequest req, ServletUpgradeResponse resp)
    {
        HttpSession httpSession = req.getSession();
        return new MySessionSocket(httpSession);
    }
}

最后,只需跟踪自己HttpSession中的WebSocket

@WebSocket
public class MySessionSocket
{
    private HttpSession httpSession;
    private Session wsSession;

    public MySessionSocket(HttpSession httpSession)
    {
        this.httpSession = httpSession;
    }

    @OnWebSocketConnect
    public void onOpen(Session wsSession)
    {
        this.wsSession = wsSession;
    }
}

值得注意的是:HttpSession可以在WebSocket处于活动状态时过期并进行清理和清理。此外,此时的HttpSession内容无法保证与其他Web操作的更改保持同步(这主要取决于您在服务器端使用的会话存储/缓存技术)

还有一点需要注意:抵制在Socket实例中存储/跟踪ServletUpgradeRequest对象的冲动,因为Jetty本身可以回收并清理这个对象。