GetClosedChannel.java

/*
 * Copyright (c) 2014, 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 8025619
 * @summary Verify that a channel obtained from a closed stream is truly closed.
 */
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.nio.channels.ClosedChannelException;
import java.nio.channels.FileChannel;

public class GetClosedChannel {
    private static final int NUM_CHANNELS = 3;
    private static final int NUM_EXCEPTIONS = 2*NUM_CHANNELS;

    public static void main(String[] args) throws IOException {
        int exceptions = 0;
        int openChannels = 0;

        for (int i = 0; i < NUM_CHANNELS; i++) {
            File f = File.createTempFile("fcbug", ".tmp");
            f.deleteOnExit();

            FileChannel fc = null;
            boolean shared = false;
            switch (i) {
                case 0:
                    System.out.print("FileInputStream...");
                    FileInputStream fis = new FileInputStream(f);
                    fis.close();
                    fc = fis.getChannel();
                    if (fc.isOpen()) {
                        System.err.println("FileInputStream channel should not be open");
                        openChannels++;
                    }
                    shared = true;
                    break;
                case 1:
                    System.out.print("FileOutputStream...");
                    FileOutputStream fos = new FileOutputStream(f);
                    fos.close();
                    fc = fos.getChannel();
                    if (fc.isOpen()) {
                        System.err.println("FileOutputStream channel should not be open");
                        openChannels++;
                    }
                    break;
                case 2:
                    System.out.print("RandomAccessFile...");
                    RandomAccessFile raf = new RandomAccessFile(f, "rw");
                    raf.close();
                    fc = raf.getChannel();
                    if (fc.isOpen()) {
                        System.err.println("RandomAccessFile channel should not be open");
                        openChannels++;
                    }
                    break;
                default:
                    assert false : "Should not get here";
            }

            try {
                long position = fc.position();
                System.err.println("Channel "+i+" position is "+position);
            } catch (ClosedChannelException cce) {
                exceptions++;
            }

            try {
                fc.tryLock(0, Long.MAX_VALUE, shared);
            } catch (ClosedChannelException e) {
                System.out.println("OK");
                exceptions++;
            } catch (Error err) {
                System.err.println(err);
            }
        }

        if (exceptions != NUM_EXCEPTIONS || openChannels != 0) {
            throw new RuntimeException("FAILED:" +
                    " ClosedChannelExceptions: expected: " + NUM_EXCEPTIONS +
                    " actual: " + exceptions + ";" + System.lineSeparator() +
                    " number of open channels: expected: 0 " +
                    " actual: " + openChannels + ".");
        }
    }
}