java/src/main/com/google/appengine/api/socket/AppEngineSocketUtils.java

   1 // Copyright 2012 Google Inc. All Rights Reserved.
   2 package com.google.appengine.api.socket;
   3
   4 import com.google.appengine.api.socket.SocketServicePb.AddressPort;
   5
   6 import java.net.InetAddress;
   7
   8 /**
   9  * Utility methods.
  10  *
  11  */
  12 class AppEngineSocketUtils {
  13   private static final int IPV6_LEN = 16;
  14   private static final int IPV4_LEN = 4;
  15
  16   /**
  17    * Convert an inet address and port to an IPv6 AddressPort. IPv4 addresses
  18    * are mapped to the IPv6 compatible address.
  19    */
  20   static AddressPort toAddressPort(InetAddress address, int port) {
  21     return new AddressPort().setPort(port).setPackedAddressAsBytes(addrAsIpv6Bytes(address));
  22   }
  23
  24   static byte[] addrAsIpv6Bytes(InetAddress address) {
  25     byte[] bytes = address.getAddress();
  26     if (bytes.length == IPV6_LEN) {
  27       return bytes;
  28     }
  29
  30     if (bytes.length == IPV4_LEN) {
  31       return new byte[] {
  32           0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, bytes[0], bytes[1], bytes[2], bytes[3]};
  33     }
  34     throw new IllegalArgumentException(
  35         "address must be IPV4 or IPV6 - unknown size: " + bytes.length);
  36   }
  37
  38   private AppEngineSocketUtils() {}
  39 }