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/*
* Copyright (c) 2002, 2004, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
import java.net.InetAddress;
import java.util.*;
import javax.naming.*;
import javax.naming.directory.*;
/*
* Tests if a canonical name (CNAME) record exists for a
* specified host - throws exception if DNS isn't configured
* or there isn't a CNAME record.
*/
public class CanonicalName {
public static void main(String args[]) throws Exception {
final Hashtable<String,String> env = new Hashtable<String,String>();
env.put("java.naming.factory.initial",
"com.sun.jndi.dns.DnsContextFactory");
DirContext ctx = new InitialDirContext(env);
String ids[] = { "CNAME" };
Attributes attrs = ctx.getAttributes(args[0], ids);
NamingEnumeration ne = attrs.getAll();
if (!ne.hasMoreElements()) {
throw new Exception("no CNAME record");
}
// print out the CNAME records
while (ne.hasMoreElements()) {
Attribute attr = (Attribute)ne.next();
for (NamingEnumeration e = attr.getAll(); e.hasMoreElements();) {
System.out.println(args[0] + " -> " + e.next());
}
}
}
}
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