Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/*
 *  PHEX - The pure-java Gnutella-servent.
 *  Copyright (C) 2001 - 2008 Phex Development Group
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program 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 for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 * 
 *  --- SVN Information ---
 *  $Id$
 */

public class Main {
    /**
     * Tries to parse the port of a host string. If no port could be parsed -1 is
     * returned.
     * @param hostName the full host string.
     * @return the port as an int or -1.
     */
    public static int parsePort(String hostName) {
        int portIdx = hostName.indexOf(':');
        if (portIdx == -1) {
            return -1;
        }

        String portString = hostName.substring(portIdx + 1);
        char[] data = portString.toCharArray();
        int port = 0;
        for (char c : data) {
            //      '0'       '9'
            if (c < 48 || c > 57) { // !digit
                break;
            }
            // shift left and add value
            port = port * 10 + c - '0';
        }
        // no port or out of range
        if (!isPortInRange(port)) {
            return -1;
        }
        return port;
    }

    /**
     * Validates a port value if it is in range ( 1 - 65535 )
     * 
     * @param port the port to verify in int value. Unsigned short ports must be
     * converted to singned int to let this function work correctly.
     * @return true if the port is in range, false otherwise.
     */
    public static boolean isPortInRange(int port) {
        return (port & 0xFFFF0000) == 0 && port != 0;
    }
}