1 /* 2 * Copyright (c) 2007, 2011, Oracle and/or its affiliates. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * - Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 11 * - Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * - Neither the name of Oracle nor the names of its 16 * contributors may be used to endorse or promote products derived 17 * from this software without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS 20 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 21 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR 23 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 24 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 25 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 26 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 27 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 28 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 29 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 /* 33 * This source code is provided to illustrate the usage of a given feature 34 * or technique and has been deliberately simplified. Additional steps 35 * required for a production-quality application, such as security checks, 36 * input validation and proper error handling, might not be present in 37 * this sample code. 38 */ 39 40 41 import java.net.InetAddress; 42 import java.net.NetworkInterface; 43 import java.net.UnknownHostException; 44 import java.net.SocketException; 45 46 /** 47 * Parses and represents a multicast address. 48 */ 49 50 class MulticastAddress { 51 private final InetAddress group; 52 private final int port; 53 private final NetworkInterface interf; 54 MulticastAddress(InetAddress group, int port, NetworkInterface interf)55 private MulticastAddress(InetAddress group, int port, NetworkInterface interf) { 56 this.group = group; 57 this.port = port; 58 this.interf = interf; 59 } 60 group()61 InetAddress group() { 62 return group; 63 } 64 port()65 int port() { 66 return port; 67 } 68 69 /** 70 * @return The network interface, may be {@code null} 71 */ interf()72 NetworkInterface interf() { 73 return interf; 74 } 75 76 /** 77 * Parses a string of the form "group:port[@interface]", returning 78 * a MulticastAddress representing the address 79 */ parse(String s)80 static MulticastAddress parse(String s) { 81 String[] components = s.split("@"); 82 if (components.length > 2) 83 throw new IllegalArgumentException("At most one '@' expected"); 84 85 // get group and port 86 String target = components[0]; 87 int len = components[0].length(); 88 int colon = components[0].lastIndexOf(':'); 89 if ((colon < 1) || (colon > (len-2))) 90 throw new IllegalArgumentException("group:port expected"); 91 String groupString = target.substring(0, colon); 92 int port = -1; 93 try { 94 port = Integer.parseInt(target.substring(colon+1, len)); 95 } catch (NumberFormatException x) { 96 throw new IllegalArgumentException(x); 97 } 98 99 // handle IPv6 literal address 100 if (groupString.charAt(0) == '[') { 101 len = groupString.length(); 102 if (groupString.charAt(len-1) != ']') 103 throw new IllegalArgumentException("missing ']'"); 104 groupString = groupString.substring(1,len-1); 105 if (groupString.length() == 0) 106 throw new IllegalArgumentException("missing IPv6 address"); 107 } 108 109 // get group address 110 InetAddress group = null; 111 try { 112 group = InetAddress.getByName(groupString); 113 } catch (UnknownHostException x) { 114 throw new IllegalArgumentException(x); 115 } 116 if (!group.isMulticastAddress()) { 117 throw new IllegalArgumentException("'" + group.getHostAddress() + 118 "' is not multicast address"); 119 } 120 121 // optional interface 122 NetworkInterface interf = null; 123 if (components.length == 2) { 124 try { 125 interf = NetworkInterface.getByName(components[1]); 126 } catch (SocketException x) { 127 throw new IllegalArgumentException(x); 128 } 129 if (interf == null) { 130 throw new IllegalArgumentException("'" + components[1] + 131 "' is not valid interface"); 132 } 133 } 134 return new MulticastAddress(group, port, interf); 135 } 136 } 137