Java example source code file (CloseTest.java)

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Java - Java tags/keywords

bytebuffer, closetest, echoservice, eof, hello, nio, premature, runtimeexception, selectionkey, selector, socketchannel, string, timed, utf-8

The CloseTest.java Java example source code

/*
 * Copyright (c) 2003, 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.
 */

/*
 *
 *
 * This unit test checks that closing the channel returned by
 * System.inheritedChannel closes the underlying network socket.
 *
 * The test launches the "echo service" with arguments to instruct the
 * service to close the channel after it receives a small message. The
 * service then delays/lingers for 15 seconds before shuting down. To
 * prove that the close works we check that we see EOF (meaning the
 * peer has closed the connection) in less than 15 seconds.
 */
import java.nio.ByteBuffer;
import java.nio.channels.*;

public class CloseTest {

    public static void main(String args[]) throws Exception {
        String msg = "HELLO";

        // Launch the service with arguments to tell it to close
        // the connection after reading 5 bytes ("HELLO"). After
        // closing the connection the service should hang around
        // for 15 seconds.

        String service_args[] = new String[2];
        service_args[0] = String.valueOf(msg.length());
        service_args[1] = String.valueOf( 15*1000 );


        SocketChannel sc = Launcher.launchWithSocketChannel("EchoService", service_args);

        // send message - service will echo the message and close the connection.

        sc.write(ByteBuffer.wrap(msg.getBytes("UTF-8")));

        // read the reply (with timeout)
        ByteBuffer bb = ByteBuffer.allocateDirect(50);
        sc.configureBlocking(false);
        Selector sel = sc.provider().openSelector();
        SelectionKey sk = sc.register(sel, SelectionKey.OP_READ);

        long to = 12 * 1000;
        for (;;) {
            long st = System.currentTimeMillis();
            sel.select(to);
            if (sk.isReadable()) {
                int n = sc.read(bb);

                // EOF
                if (n < 0) {
                    break;
                }
            }
            sel.selectedKeys().remove(sk);
            to -= System.currentTimeMillis() - st;
            if (to <= 0) {
                throw new RuntimeException("Timed out waiting for connection to close");
            }
        }
        sel.close();
        sc.close();

        // finally check that the reply length is okay
        bb.flip();
        if (bb.remaining() < msg.length()) {
            throw new RuntimeException("Premature EOF from echo service");
        }

        System.out.println("Test passed - service closed connection.");
    }
}