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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2014 Red Hat, Inc., and individual contributors
 * as indicated by the @author tags.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */

package io.undertow.server.handlers.sse;

import io.undertow.UndertowLogger;
import io.undertow.server.HttpHandler;
import io.undertow.server.HttpServerExchange;
import io.undertow.util.Headers;
import io.undertow.util.HttpString;
import io.undertow.util.PathTemplateMatch;
import org.xnio.ChannelExceptionHandler;
import org.xnio.ChannelListener;
import org.xnio.ChannelListeners;
import org.xnio.IoUtils;
import org.xnio.channels.StreamSinkChannel;

import java.io.IOException;
import java.util.Collections;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;

/**
 * @author Stuart Douglas
 */
public class ServerSentEventHandler implements HttpHandler {

    private static final HttpString LAST_EVENT_ID = new HttpString("Last-Event-ID");

    private final ServerSentEventConnectionCallback callback;

    private final Set connections = Collections.newSetFromMap(new ConcurrentHashMap());

    public ServerSentEventHandler(ServerSentEventConnectionCallback callback) {
        this.callback = callback;
    }

    public ServerSentEventHandler() {
        this.callback = null;
    }

    @Override
    public void handleRequest(final HttpServerExchange exchange) throws Exception {
        exchange.getResponseHeaders().put(Headers.CONTENT_TYPE, "text/event-stream; charset=UTF-8");
        exchange.setPersistent(false);
        final StreamSinkChannel sink = exchange.getResponseChannel();
        if(!sink.flush()) {
            sink.getWriteSetter().set(ChannelListeners.flushingChannelListener(new ChannelListener() {
                @Override
                public void handleEvent(StreamSinkChannel channel) {
                    handleConnect(channel, exchange);
                }
            }, new ChannelExceptionHandler() {
                @Override
                public void handleException(StreamSinkChannel channel, IOException exception) {
                    IoUtils.safeClose(exchange.getConnection());
                }
            }));
            sink.resumeWrites();
        } else {
            exchange.dispatch(exchange.getIoThread(), new Runnable() {
                @Override
                public void run() {
                    handleConnect(sink, exchange);
                }
            });
        }
    }

    private void handleConnect(StreamSinkChannel channel, HttpServerExchange exchange) {
        UndertowLogger.REQUEST_LOGGER.debugf("Opened SSE connection to %s", exchange);
        final ServerSentEventConnection connection = new ServerSentEventConnection(exchange, channel);
        PathTemplateMatch pt = exchange.getAttachment(PathTemplateMatch.ATTACHMENT_KEY);
        if(pt != null) {
            for(Map.Entry p : pt.getParameters().entrySet()) {
                connection.setParameter(p.getKey(), p.getValue());
            }
        }
        connections.add(connection);
        connection.addCloseTask(new ChannelListener() {
            @Override
            public void handleEvent(ServerSentEventConnection channel) {
                connections.remove(connection);
            }
        });
        if(callback != null) {
            callback.connected(connection, exchange.getRequestHeaders().getLast(LAST_EVENT_ID));
        }
    }

    public Set getConnections() {
        return Collections.unmodifiableSet(connections);
    }
}




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