ethernetaddress.java

来自「纯java操作系统jnode,安装简单和操作简单的个人使用的Java操作系统」· Java 代码 · 共 202 行

/*
 * $Id: EthernetAddress.java,v 1.1 2003/11/25 11:52:25 epr Exp $
 */
package org.jnode.net.ethernet;

import java.io.Serializable;
import java.util.StringTokenizer;

import org.jnode.net.HardwareAddress;
import org.jnode.net.SocketBuffer;
import org.jnode.util.NumberUtils;

/**
 * Wrapper for an 6-byte ethernet address. Also called MAC address.
 * @author epr
 */
public class EthernetAddress implements HardwareAddress, Serializable {
	
	private final byte[] address;
	private final int length = EthernetConstants.ETH_ALEN;
	public static final EthernetAddress BROADCAST = new EthernetAddress("FF-FF-FF-FF-FF-FF");
	
	/**
	 * Create a new instance
	 * @param address
	 * @param offset
	 */
	public EthernetAddress(byte[] address, int offset) 
	throws IllegalArgumentException {
		if (offset + length > address.length) {
			throw new IllegalArgumentException("Invalid address length");
		}
		this.address = new byte[length];
		System.arraycopy(address, offset, this.address, 0, length);
	}
	
	/**
	 * Create a new instance
	 * @param skbuf
	 * @param offset
	 */
	public EthernetAddress(SocketBuffer skbuf, int offset) 
	throws IllegalArgumentException {
		this.address = new byte[length];
		skbuf.get(address, 0, offset, length);
	}
	
	/**
	 * Create a new instance
	 * @param addressStr
	 */
	public EthernetAddress(String addressStr) 
	throws IllegalArgumentException {
		final StringTokenizer tok = new StringTokenizer(addressStr, "-:");
		if (tok.countTokens() != length) {
			throw new IllegalArgumentException("Invalid address " + addressStr);
		}
		address = new byte[length];
		for (int i = 0; i < length; i++) {
			try {
				address[i] = (byte)Integer.parseInt(tok.nextToken(), 16);
			} catch (NumberFormatException ex) {
				throw new IllegalArgumentException("Not an ethernet address " + addressStr);
			}
		}
	}
	
	/**
	 * Create a new instance
	 * @param b0
	 * @param b1
	 * @param b2
	 * @param b3
	 * @param b5
	 */
	public EthernetAddress(byte b0, byte b1, byte b2, byte b3, byte b4, byte b5) {
		address = new byte[length];
		address[0] = b0;
		address[1] = b1;
		address[2] = b2;
		address[3] = b3;
		address[4] = b4;
		address[5] = b5;
	}
	
	/**
	 * Is this address equal to the given address.
	 * @param o
	 */
	public boolean equals(EthernetAddress o) {
		for (int i = 0; i < length; i++) {
			if (this.address[i] != o.address[i]) {
				return false;
			}
		}
		return true;
	}

	/**
	 * Is this address equal to the given address.
	 * @param o
	 */
	public boolean equals(HardwareAddress o) {
		if (o instanceof EthernetAddress) {
			return equals((EthernetAddress)o);
		} else {
			return false;
		}
	}
	
	/**
	 * Is this address equal to the given address.
	 * @param o
	 */
	public boolean equals(Object o) {
		if (o instanceof EthernetAddress) {
			return equals((EthernetAddress)o);
		} else {
			return false;
		}
	}
	
	/**
	 * Gets the length of this address in bytes
	 */
	public final int getLength() {
		return length;
	}
	
	/**
	 * Gets the address-byte at a given index
	 * @param index
	 */
	public final byte get(int index) {
		return address[index];
	}
	
	/**
	 * Write this address to a given offset in the given buffer
	 * @param skbuf
	 * @param skbufOffset
	 */
	public void writeTo(SocketBuffer skbuf, int skbufOffset) {
		skbuf.set(skbufOffset, address, 0, length);
	}

	/**
	 * Is this a broadcast address?
	 */
	public boolean isBroadcast() {
		for (int i = 0; i < length; i++) {
			if (address[i] != 0xFF) {
				return false;
			}
		}
		return true;
	}
	

	/**
	 * Gets the default broadcast address for this kind of hardware address.
	 */
	public HardwareAddress getDefaultBroadcastAddress() {
		return BROADCAST;
	}
	
	
	/**
	 * Gets the type of this address.
	 * This type is used by (e.g.) ARP.
	 */
	public int getType() {
		return 1; // For ethernet	
	}
	
	/**
	 * Convert this address to a string representation
	 * @see java.lang.Object#toString()
	 */
	public String toString() {
		final StringBuffer b = new StringBuffer();
		for (int i = 0; i < length; i++) {
			if (i > 0) {
				b.append(':');
			}
			b.append(NumberUtils.hex(address[i] & 0xFF, 2));
		}
		return b.toString();
	}

	/**
	 * @see java.lang.Object#hashCode()
	 */
	public int hashCode() {
		int v = 0;
		for (int i = 0; i < length; i++) {
			v ^= (address[i] & 0xFF) << (i*3);
		}
		return v;
	}
}