/*

 * Copyright (c) 2004, 2011, Oracle and/or its affiliates. All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *

 *   - Redistributions of source code must retain the above copyright

 *     notice, this list of conditions and the following disclaimer.

 *

 *   - Redistributions in binary form must reproduce the above copyright

 *     notice, this list of conditions and the following disclaimer in the

 *     documentation and/or other materials provided with the distribution.

 *

 *   - Neither the name of Oracle nor the names of its

 *     contributors may be used to endorse or promote products derived

 *     from this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS

 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,

 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR

 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

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 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

/*

 * This source code is provided to illustrate the usage of a given feature

 * or technique and has been deliberately simplified. Additional steps

 * required for a production-quality application, such as security checks,

 * input validation and proper error handling, might not be present in

 * this sample code.

 */

import java.io.*;

import java.net.*;

import java.nio.channels.*;

import java.security.*;

import javax.net.ssl.*;

/**

 * The main server base class.

 * <P>

 * This class is responsible for setting up most of the server state

 * before the actual server subclasses take over.

 *

 * @author Mark Reinhold

 * @author Brad R. Wetmore

 */

public abstract class Server {

    ServerSocketChannel ssc;

    SSLContext sslContext = null;

    static private int PORT = 8000;

    static private int BACKLOG = 1024;

    static private boolean SECURE = false;

    Server(int port, int backlog,

            boolean secure) throws Exception {

        if (secure) {

            createSSLContext();

        }

        ssc = ServerSocketChannel.open();

        ssc.socket().setReuseAddress(true);

        ssc.socket().bind(new InetSocketAddress(port), backlog);

    }

    /*

     * If this is a secure server, we now setup the SSLContext we'll

     * use for creating the SSLEngines throughout the lifetime of

     * this process.

     */

    private void createSSLContext() throws Exception {

        char[] passphrase = "passphrase".toCharArray();

        KeyStore ks = KeyStore.getInstance("JKS");

        ks.load(new FileInputStream("testkeys"), passphrase);

        KeyManagerFactory kmf = KeyManagerFactory.getInstance("SunX509");

        kmf.init(ks, passphrase);

        TrustManagerFactory tmf = TrustManagerFactory.getInstance("SunX509");

        tmf.init(ks);

        sslContext = SSLContext.getInstance("TLS");

        sslContext.init(kmf.getKeyManagers(), tmf.getTrustManagers(), null);

    }

    abstract void runServer() throws Exception;

    static private void usage() {

        System.out.println(

            "Usage:  Server <type> [options]\n"

                + "     type:\n"

                + "             B1      Blocking/Single-threaded Server\n"

                + "             BN      Blocking/Multi-threaded Server\n"

                + "             BP      Blocking/Pooled-Thread Server\n"

                + "             N1      Nonblocking/Single-threaded Server\n"

                + "             N2      Nonblocking/Dual-threaded Server\n"

                + "\n"

                + "     options:\n"

                + "             -port port              port number\n"

                + "                 default:  " + PORT + "\n"

                + "             -backlog backlog        backlog\n"

                + "                 default:  " + BACKLOG + "\n"

                + "             -secure                 encrypt with SSL/TLS");

        System.exit(1);

    }

    /*

     * Parse the arguments, decide what type of server to run,

     * see if there are any defaults to change.

     */

    static private Server createServer(String args[]) throws Exception {

        if (args.length < 1) {

            usage();

        }

        int port = PORT;

        int backlog = BACKLOG;

        boolean secure = SECURE;

        for (int i = 1; i < args.length; i++) {

            if (args[i].equals("-port")) {

                checkArgs(i, args.length);

                port = Integer.valueOf(args[++i]);

            } else if (args[i].equals("-backlog")) {

                checkArgs(i, args.length);

                backlog = Integer.valueOf(args[++i]);

            } else if (args[i].equals("-secure")) {

                secure = true;

            } else {

                usage();

            }

        }

        Server server = null;

        if (args[0].equals("B1")) {

            server = new B1(port, backlog, secure);

        } else if (args[0].equals("BN")) {

            server = new BN(port, backlog, secure);

        } else if (args[0].equals("BP")) {

            server = new BP(port, backlog, secure);

        } else if (args[0].equals("N1")) {

            server = new N1(port, backlog, secure);

        } else if (args[0].equals("N2")) {

            server = new N2(port, backlog, secure);

        }

        return server;

    }

    static private void checkArgs(int i, int len) {

        if ((i + 1) >= len) {

           usage();

        }

    }

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

        Server server = createServer(args);

        if (server == null) {

            usage();

        }

        System.out.println("Server started.");

        server.runServer();

    }

}