Java example source code file (B6521014.java)

This example Java source code file (B6521014.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

b6521014, enumeration, exception, inet6address, inetaddress, inetsocketaddress, ioexception, net, network, networkinterface, runtimeexception, serversocket, socket, sockettimeoutexception, test, util

The B6521014.java Java example source code

/*
 * Copyright (c) 2007, 2013, 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.
 */

/*
 * @test
 * @bug 6521014 6543428
 * @summary IOException thrown when Socket tries to bind to an local IPv6 address on SuSE Linux
 */


import java.net.*;
import java.io.*;
import java.util.*;


/*
 *
 * What this testcase is to test is a (weird) coupling through the
 * cached_scope_id field of java.net.Inet6Address. Native method
 * NET_InetAddressToSockaddr as in Linux platform will try to write
 * and read this field, therefore Inet6Address becomes 'stateful'.
 * So the coupling. Certain executive order, e.g. two methods use
 * the same Inet6Address instance as illustrated in this test case,
 * will show side effect of such coupling.
 *
 * And on Windows, NET_InetAddressToSockaddr() did not assign appropriate
 * sin6_scope_id value to sockaddr_in6 structure if there's no one coming
 * with Inet6Address instance, which caused bind exception. This test use
 * link-local address without %scope suffix, so it is also going to test
 * that.
 *
 */
public class B6521014 {

    static InetAddress sin;

    static Inet6Address getLocalAddr () throws Exception {
        Enumeration e = NetworkInterface.getNetworkInterfaces();
        while (e.hasMoreElements()) {
            NetworkInterface ifc = (NetworkInterface) e.nextElement();
            if (!ifc.isUp())
                continue;
            Enumeration addrs = ifc.getInetAddresses();
            while (addrs.hasMoreElements()) {
                InetAddress a = (InetAddress)addrs.nextElement();
                if (a instanceof Inet6Address) {
                    Inet6Address ia6 = (Inet6Address) a;
                    if (ia6.isLinkLocalAddress()) {
                        // remove %scope suffix
                        return (Inet6Address)InetAddress.getByAddress(ia6.getAddress());
                    }
                }
            }
        }
        return null;
    }

    static void test1() throws Exception {
        ServerSocket ssock;
        Socket sock;
        int port;

        ssock = new ServerSocket(0);
        port = ssock.getLocalPort();
        sock = new Socket();
        try {
            sock.connect(new InetSocketAddress(sin, port), 100);
        } catch (SocketTimeoutException e) {
            // time out exception is okay
            System.out.println("timed out when connecting.");
        }
    }

    static void test2() throws Exception {
        Socket sock;
        ServerSocket ssock;
        int port;

        ssock = new ServerSocket(0);
        ssock.setSoTimeout(100);
        port = ssock.getLocalPort();
        sock = new Socket();
        sock.bind(new InetSocketAddress(sin, 0));
        try {
            sock.connect(new InetSocketAddress(sin, port), 100);
        } catch (SocketTimeoutException e) {
            // time out exception is okay
            System.out.println("timed out when connecting.");
        }
    }

    public static void main(String[] args) throws Exception {
        sin = getLocalAddr();
        if (sin == null) {
            System.out.println("Cannot find a link-local address.");
            return;
        }

        try {
            test1();
            test2();
        } catch (IOException e) {
            throw new RuntimeException("Test failed: cannot create socket.", e);
        }
    }
}