Source for java.net.Inet4Address

   1: /* Inet4Address.java --
   2:    Copyright (C) 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
   3: 
   4: This file is part of GNU Classpath.
   5: 
   6: GNU Classpath is free software; you can redistribute it and/or modify
   7: it under the terms of the GNU General Public License as published by
   8: the Free Software Foundation; either version 2, or (at your option)
   9: any later version.
  10: 
  11: GNU Classpath is distributed in the hope that it will be useful, but
  12: WITHOUT ANY WARRANTY; without even the implied warranty of
  13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14: General Public License for more details.
  15: 
  16: You should have received a copy of the GNU General Public License
  17: along with GNU Classpath; see the file COPYING.  If not, write to the
  18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 USA.
  20: 
  21: Linking this library statically or dynamically with other modules is
  22: making a combined work based on this library.  Thus, the terms and
  23: conditions of the GNU General Public License cover the whole
  24: combination.
  25: 
  26: As a special exception, the copyright holders of this library give you
  27: permission to link this library with independent modules to produce an
  28: executable, regardless of the license terms of these independent
  29: modules, and to copy and distribute the resulting executable under
  30: terms of your choice, provided that you also meet, for each linked
  31: independent module, the terms and conditions of the license of that
  32: module.  An independent module is a module which is not derived from
  33: or based on this library.  If you modify this library, you may extend
  34: this exception to your version of the library, but you are not
  35: obligated to do so.  If you do not wish to do so, delete this
  36: exception statement from your version. */
  37: 
  38: 
  39: package java.net;
  40: 
  41: import java.io.ObjectStreamException;
  42: 
  43: /*
  44:  * Written using on-line Java Platform 1.4 API Specification and
  45:  * RFC 1884 (http://www.ietf.org/rfc/rfc1884.txt),
  46:  * RFC 1918 (http://www.ietf.org/rfc/rfc1918.txt),
  47:  * RFC 2365 (http://www.ietf.org/rfc/rfc2365.txt)
  48:  *
  49:  * @author Michael Koch
  50:  * @status Believed complete and correct.
  51:  */
  52: public final class Inet4Address extends InetAddress
  53: {
  54:   /**
  55:    * For compatability with Sun's JDK 1.4.2 rev. 5
  56:    */
  57:   static final long serialVersionUID = 3286316764910316507L;
  58: 
  59:   /**
  60:    * The address family of these addresses (used for serialization).
  61:    */
  62:   private static final int AF_INET = 2;
  63: 
  64:   /**
  65:    * Inet4Address objects are serialized as InetAddress objects.
  66:    */
  67:   private Object writeReplace() throws ObjectStreamException
  68:   {
  69:     return new InetAddress(addr, hostName, AF_INET);
  70:   }
  71:   
  72:   /**
  73:    * Initializes this object's addr instance variable from the passed in
  74:    * byte array.  Note that this constructor is protected and is called
  75:    * only by static methods in this class.
  76:    *
  77:    * @param addr The IP number of this address as an array of bytes
  78:    * @param host The hostname of this IP address.
  79:    */
  80:   Inet4Address(byte[] addr, String host)
  81:   {
  82:     super(addr, host, AF_INET);
  83:   }
  84: 
  85:   /**
  86:    * Checks if the address is a multicast address
  87:    *
  88:    * @since 1.1
  89:    */
  90:   public boolean isMulticastAddress()
  91:   {
  92:     return (addr[0] & 0xf0) == 0xe0;
  93:   }
  94: 
  95:   /**
  96:    * Checks if this address is a loopback address
  97:    */
  98:   public boolean isLoopbackAddress()
  99:   {
 100:     return (addr[0] & 0xff) == 0x7f;
 101:   }
 102: 
 103:   /**
 104:    * Checks if this address is a wildcard address
 105:    *
 106:    * @since 1.4
 107:    */
 108:   public boolean isAnyLocalAddress()
 109:   {
 110:     return equals(InetAddress.ANY_IF);
 111:   }
 112: 
 113:   /**
 114:    * Checks if this address is a link local address
 115:    *
 116:    * @since 1.4
 117:    */
 118:   public boolean isLinkLocalAddress()
 119:   {
 120:     return false;
 121:   }
 122: 
 123:   /**
 124:    * Checks if this address is a site local address
 125:    *
 126:    * @since 1.4
 127:    */
 128:   public boolean isSiteLocalAddress()
 129:   {
 130:     // 10.0.0.0/8
 131:     if ((addr[0] & 0xff) == 0x0a)
 132:       return true;
 133: 
 134:     // 172.16.0.0/12
 135:     if ((addr[0] & 0xff) == 0xac && (addr[1] & 0xf0) == 0x10)
 136:       return true;
 137: 
 138:     // 192.168.0.0/16
 139:     if ((addr[0] & 0xff) == 0xc0 && (addr[1] & 0xff) == 0xa8)
 140:       return true;
 141: 
 142:     return false;
 143:   }
 144: 
 145:   /**
 146:    * Checks if this multicast address has global scope
 147:    *
 148:    * @since 1.4
 149:    */
 150:   public boolean isMCGlobal()
 151:   {
 152:     return false;
 153:   }
 154: 
 155:   /**
 156:    * Checks if this multicast address has node scope
 157:    *
 158:    * @since 1.4
 159:    */
 160:   public boolean isMCNodeLocal()
 161:   {
 162:     return false;
 163:   }
 164: 
 165:   /**
 166:    * Checks if this multicast address has link scope
 167:    *
 168:    * @since 1.4
 169:    */
 170:   public boolean isMCLinkLocal()
 171:   {
 172:     if (! isMulticastAddress())
 173:       return false;
 174: 
 175:     return ((addr[0] & 0xff) == 0xe0
 176:         && (addr[1] & 0xff)  == 0x00
 177:         && (addr[2] & 0xff)  == 0x00);
 178:   }
 179: 
 180:   /**
 181:    * Checks if this multicast address has site scope
 182:    *
 183:    * @since 1.4
 184:    */
 185:   public boolean isMCSiteLocal()
 186:   {
 187:     return false;
 188:   }
 189: 
 190:   /**
 191:    * Checks if this multicast address has organization scope
 192:    *
 193:    * @since 1.4
 194:    */
 195:   public boolean isMCOrgLocal()
 196:   {
 197:     return false;
 198:   }
 199: 
 200:   /**
 201:    * Returns the address of the current instance
 202:    */
 203:   public byte[] getAddress()
 204:   {
 205:     return (byte[]) addr.clone();
 206:   }
 207: 
 208:   /**
 209:    * Returns the address as string
 210:    *
 211:    * @since 1.0.2
 212:    */
 213:   public String getHostAddress()
 214:   {
 215:     StringBuffer sb = new StringBuffer(40);
 216: 
 217:     int len = addr.length;
 218:     int i = 0;
 219:     
 220:     for ( ; ; )
 221:       {
 222:         sb.append(addr[i] & 0xff);
 223:         i++;
 224:     
 225:         if (i == len)
 226:           break;
 227:     
 228:         sb.append('.');
 229:       }
 230: 
 231:     return sb.toString();
 232:   }
 233: 
 234:   /**
 235:    * Computes the hashcode of the instance
 236:    */
 237:   public int hashCode()
 238:   {
 239:     int hash = 0;
 240:     int len = addr.length;
 241:     int i = len > 4 ? len - 4 : 0;
 242: 
 243:     for (; i < len; i++)
 244:       hash = (hash << 8) | (addr[i] & 0xFF);
 245: 
 246:     return hash;
 247:   }
 248: 
 249:   /**
 250:    * Compare the current Inet4Address instance with obj
 251:    *
 252:    * @param obj Object to compare with
 253:    */
 254:   public boolean equals(Object obj)
 255:   {
 256:     if (! (obj instanceof InetAddress))
 257:       return false;
 258: 
 259:     byte[] addr1 = addr;
 260:     byte[] addr2 = ((InetAddress) obj).addr;
 261: 
 262:     if (addr1.length != addr2.length)
 263:       return false;
 264: 
 265:     for (int i = addr1.length; --i >= 0;)
 266:       if (addr1[i] != addr2[i])
 267:     return false;
 268: 
 269:     return true;
 270:   }
 271: }