Examples with ServletContextListener javax.servlet.ServletContextListener used on opensource projects

Example 21 with ServletContextListener

use of javax.servlet.ServletContextListener in project undertow by undertow-io.

the class ServerSentEventSCI method onStartup.

@Override
public void onStartup(Set<Class<?>> c, ServletContext ctx) throws ServletException {
    if (c == null || c.isEmpty()) {
        return;
    }
    try {
        final Map<String, ServerSentEventConnectionCallback> callbacks = new HashMap<>();
        ServletContextImpl servletContext = (ServletContextImpl) ctx;
        final List<InstanceHandle<?>> handles = new ArrayList<>();
        for (Class<?> clazz : c) {
            final ServerSentEvent annotation = clazz.getAnnotation(ServerSentEvent.class);
            if (annotation == null) {
                continue;
            }
            String path = annotation.value();
            final InstanceHandle<?> instance = servletContext.getDeployment().getDeploymentInfo().getClassIntrospecter().createInstanceFactory(clazz).createInstance();
            handles.add(instance);
            callbacks.put(path, (ServerSentEventConnectionCallback) instance.getInstance());
        }
        if (callbacks.isEmpty()) {
            return;
        }
        servletContext.getDeployment().getDeploymentInfo().addInnerHandlerChainWrapper(new HandlerWrapper() {

            @Override
            public HttpHandler wrap(HttpHandler handler) {
                PathTemplateHandler pathTemplateHandler = new PathTemplateHandler(handler, false);
                for (Map.Entry<String, ServerSentEventConnectionCallback> e : callbacks.entrySet()) {
                    pathTemplateHandler.add(e.getKey(), new ServerSentEventHandler(e.getValue()));
                }
                return pathTemplateHandler;
            }
        });
        servletContext.addListener(new ServletContextListener() {

            @Override
            public void contextInitialized(ServletContextEvent sce) {
            }

            @Override
            public void contextDestroyed(ServletContextEvent sce) {
                for (InstanceHandle<?> h : handles) {
                    h.release();
                }
            }
        });
    } catch (Exception e) {
        throw new ServletException(e);
    }
}