com.bitctrl.net.MAC.java Source code

Introduction

Here is the source code for com.bitctrl.net.MAC.java

Source

/*
 * Java Common Library
 * Copyright (c) 2008 BitCtrl Systems GmbH
 *
 * This library is free software; you can redistribute it and/or modify it under
 * the terms of the GNU Lesser General Public License as published by the Free
 * Software Foundation; either version 3.0 of the License, or (at your option)
 * any later version.
 *
 * This library 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 Lesser General Public License for more
 * details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this library; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA.
 *
 * Contact Information:
 * BitCtrl Systems GmbH
 * Weienfelser Strae 67
 * 04229 Leipzig
 * Phone: +49 341-490670
 * mailto: info@bitctrl.de
 */

package com.bitctrl.net;

import java.io.Serializable;
import java.util.Arrays;

import org.apache.commons.codec.DecoderException;
import org.apache.commons.codec.binary.Hex;

/**
 * Diese Klasse stellt eine MAC-Adresse dar.
 * 
 * @author BitCtrl Systems GmbH, Schumann
 */
public class MAC implements Serializable {

    private static final long serialVersionUID = 1L;

    /**
     * Bestimmt aus einem String die MAC-Adresse. Der String muss im Format
     * {@code x:x:x:x:x:x} vorliegen.
     * 
     * @param address
     *            die Adresse als Zeichenkette
     * @return die Adresse
     * @throws IllegalArgumentException
     *             die bergebene Zeichenkette konnte nicht interpretiert werden
     */
    public static MAC valueOf(final String address) throws IllegalArgumentException {
        if (address == null || address.length() == 0) {
            return null;
        }

        final String hex = address.replace(":", "");
        try {
            final byte[] data = Hex.decodeHex(hex.toCharArray());
            if (data.length != 6) {
                throw new IllegalArgumentException("Can not determine MAC address.");
            }
            return new MAC(data);
        } catch (final DecoderException ex) {
            throw new IllegalArgumentException("Can not determine MAC address.", ex);
        }
    }

    private final byte[] address;

    /**
     * Initialisiert die MAC-Adresse.
     * 
     * @param address
     *            die sechs Bytes der MAC-Adresse.
     */
    public MAC(final byte[] address) {
        if (address.length != 6) {
            throw new IllegalArgumentException("MAC address must have 6 bytes.");
        }
        this.address = address;
    }

    /**
     * Verwendet {@link #valueOf(String)} zur Initialisierung der MAC-Adresse.
     * 
     * @param address
     *            ein String, der eine MAC-Adresse darstellt.
     * @throws IllegalArgumentException
     *             die bergebene Zeichenkette konnte nicht interpretiert werden
     */
    public MAC(final String address) throws IllegalArgumentException {
        this.address = valueOf(address).getAddress();
    }

    /**
     * Gibt die MAC-Adresse als Bytefeld zurck.
     * 
     * @return das Bytefeld
     */
    public byte[] getAddress() {
        return address;
    }

    @Override
    public boolean equals(final Object obj) {
        if (this == obj) {
            return true;
        } else if (obj instanceof MAC) {
            final MAC o = (MAC) obj;
            return Arrays.equals(address, o.address);
        }

        return false;
    }

    @Override
    public int hashCode() {
        return Arrays.hashCode(address);
    }

    @Override
    public String toString() {
        final char[] hex = Hex.encodeHex(address);
        String s = "";
        for (int i = 0; i < hex.length; ++i) {
            s += hex[i];
            if (i % 2 == 1 && i < hex.length - 1) {
                // Nach jedem Byte (2 Hexziffern) Trenzeichen einfgen.
                s += ':';
            }
        }

        return s;
    }
}