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/*
* Copyright (c) 2007, 2011, Oracle and/or its affiliates. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the name of Oracle nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
* IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* This source code is provided to illustrate the usage of a given feature
* or technique and has been deliberately simplified. Additional steps
* required for a production-quality application, such as security checks,
* input validation and proper error handling, might not be present in
* this sample code.
*/
import java.net.InetAddress;
import java.net.NetworkInterface;
import java.net.UnknownHostException;
import java.net.SocketException;
/**
* Parses and represents a multicast address.
*/
class MulticastAddress {
private final InetAddress group;
private final int port;
private final NetworkInterface interf;
private MulticastAddress(InetAddress group, int port, NetworkInterface interf) {
this.group = group;
this.port = port;
this.interf = interf;
}
InetAddress group() {
return group;
}
int port() {
return port;
}
/**
* @return The network interface, may be {@code null}
*/
NetworkInterface interf() {
return interf;
}
/**
* Parses a string of the form "group:port[@interface]", returning
* a MulticastAddress representing the address
*/
static MulticastAddress parse(String s) {
String[] components = s.split("@");
if (components.length > 2)
throw new IllegalArgumentException("At most one '@' expected");
// get group and port
String target = components[0];
int len = components[0].length();
int colon = components[0].lastIndexOf(':');
if ((colon < 1) || (colon > (len-2)))
throw new IllegalArgumentException("group:port expected");
String groupString = target.substring(0, colon);
int port = -1;
try {
port = Integer.parseInt(target.substring(colon+1, len));
} catch (NumberFormatException x) {
throw new IllegalArgumentException(x);
}
// handle IPv6 literal address
if (groupString.charAt(0) == '[') {
len = groupString.length();
if (groupString.charAt(len-1) != ']')
throw new IllegalArgumentException("missing ']'");
groupString = groupString.substring(1,len-1);
if (groupString.length() == 0)
throw new IllegalArgumentException("missing IPv6 address");
}
// get group address
InetAddress group = null;
try {
group = InetAddress.getByName(groupString);
} catch (UnknownHostException x) {
throw new IllegalArgumentException(x);
}
if (!group.isMulticastAddress()) {
throw new IllegalArgumentException("'" + group.getHostAddress() +
"' is not multicast address");
}
// optional interface
NetworkInterface interf = null;
if (components.length == 2) {
try {
interf = NetworkInterface.getByName(components[1]);
} catch (SocketException x) {
throw new IllegalArgumentException(x);
}
if (interf == null) {
throw new IllegalArgumentException("'" + components[1] +
"' is not valid interface");
}
}
return new MulticastAddress(group, port, interf);
}
}
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