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 * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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package com.sun.xml.internal.ws.transport.http.server;

import com.sun.net.httpserver.HttpContext;

import com.sun.net.httpserver.HttpServer;

import com.sun.xml.internal.ws.server.ServerRtException;

import java.net.InetSocketAddress;

import java.net.URL;

import java.util.HashMap;

import java.util.HashSet;

import java.util.Map;

import java.util.Set;

import java.util.concurrent.ExecutorService;

import java.util.concurrent.Executors;

import java.util.logging.Logger;

/**

 * Manages all the WebService HTTP servers created by JAXWS runtime.

 *

 * @author Jitendra Kotamraju

 */

final class ServerMgr {

    private static final ServerMgr serverMgr = new ServerMgr();

    private static final Logger logger =

        Logger.getLogger(

            com.sun.xml.internal.ws.util.Constants.LoggingDomain + ".server.http");

    private final Map<InetSocketAddress,ServerState> servers = new HashMap<InetSocketAddress,ServerState>();

    private ServerMgr() {}

    /**

     * Gets the singleton instance.

     * @return manager instance

     */

    static ServerMgr getInstance() {

        return serverMgr;

    }

    /*

     * Creates a HttpContext at the given address. If there is already a server

     * it uses that server to create a context. Otherwise, it creates a new

     * HTTP server. This sever is added to servers Map.

     */

    /*package*/ HttpContext createContext(String address) {

        try {

            HttpServer server;

            ServerState state;

            URL url = new URL(address);

            int port = url.getPort();

            if (port == -1) {

                port = url.getDefaultPort();

            }

            InetSocketAddress inetAddress = new InetSocketAddress(url.getHost(),

                port);

            synchronized(servers) {

                state = servers.get(inetAddress);

                if (state == null) {

                    logger.fine("Creating new HTTP Server at "+inetAddress);

                    // Creates server with default socket backlog

                    server = HttpServer.create(inetAddress, 0);

                    server.setExecutor(Executors.newCachedThreadPool());

                    String path = url.toURI().getPath();

                    logger.fine("Creating HTTP Context at = "+path);

                    HttpContext context = server.createContext(path);

                    server.start();

                    // we have to get actual inetAddress from server, which can differ from the original in some cases.

                    // e.g. A port number of zero will let the system pick up an ephemeral port in a bind operation,

                    // or IP: 0.0.0.0 - which is used to monitor network traffic from any valid IP address

                    inetAddress = server.getAddress();

                    logger.fine("HTTP server started = "+inetAddress);

                    state = new ServerState(server, path);

                    servers.put(inetAddress, state);

                    return context;

                }

            }

            server = state.getServer();

            if (state.getPaths().contains(url.getPath())) {

              String err = "Context with URL path "+url.getPath()+ " already exists on the server "+server.getAddress();

              logger.fine(err);

              throw new IllegalArgumentException(err);

            }

            logger.fine("Creating HTTP Context at = "+url.getPath());

            HttpContext context = server.createContext(url.getPath());

            state.oneMoreContext(url.getPath());

            return context;

        } catch(Exception e) {

            throw new ServerRtException("server.rt.err",e );

        }

    }

    /*

     * Removes a context. If the server doesn't have anymore contexts, it

     * would stop the server and server is removed from servers Map.

     */

    /*package*/ void removeContext(HttpContext context) {

        InetSocketAddress inetAddress = context.getServer().getAddress();

        synchronized(servers) {

            ServerState state = servers.get(inetAddress);

            int instances = state.noOfContexts();

            if (instances < 2) {

                ((ExecutorService)state.getServer().getExecutor()).shutdown();

                state.getServer().stop(0);

                servers.remove(inetAddress);

            } else {

                state.getServer().removeContext(context);

                state.oneLessContext(context.getPath());

            }

        }

    }

    private static final class ServerState {

        private final HttpServer server;

        private int instances;

        private Set<String> paths = new HashSet<String>();

        ServerState(HttpServer server, String path) {

            this.server = server;

            this.instances = 1;

            paths.add(path);

        }

        public HttpServer getServer() {

            return server;

        }

        public void oneMoreContext(String path) {

            ++instances;

            paths.add(path);

        }

        public void oneLessContext(String path) {

            --instances;

            paths.remove(path);

        }

        public int noOfContexts() {

            return instances;

        }

        public Set<String> getPaths() {

          return paths;

        }

    }

}