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 * Copyright (c) 2018, 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.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * 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,

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 *

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package jdk.jfr.event.io;

import static jdk.test.lib.Asserts.assertEquals;

import java.io.File;

import java.io.RandomAccessFile;

import java.time.Duration;

import java.util.ArrayList;

import java.util.List;

import jdk.jfr.Recording;

import jdk.jfr.consumer.RecordedEvent;

import jdk.test.lib.jfr.Events;

/*

 * @test

 * @key jfr

 * @library /test/lib /test/jdk

 * @run main/othervm jdk.jfr.event.io.TestRandomAccessFileEvents

 */

public class TestRandomAccessFileEvents {

    public static void main(String[] args) throws Throwable {

        File tmp = File.createTempFile("TestRandomAccessFileEvents", ".tmp", new File("."));

        tmp.deleteOnExit();

        Recording recording = new Recording();

        List<IOEvent> expectedEvents = new ArrayList<>();

        recording.enable(IOEvent.EVENT_FILE_WRITE).withThreshold(Duration.ofMillis(0));

        recording.enable(IOEvent.EVENT_FILE_READ).withThreshold(Duration.ofMillis(0));

        recording.start();

        RandomAccessFile ras = new RandomAccessFile(tmp, "rw");

        int writeInt = 47;

        byte[] writeBuffer = {10,11,12,13};

        // Write an int and a buffer.

        ras.write(writeInt);

        expectedEvents.add(IOEvent.createFileWriteEvent(1, tmp));

        ras.write(writeBuffer);

        expectedEvents.add(IOEvent.createFileWriteEvent(writeBuffer.length, tmp));

        ras.seek(0);

        // Read int and buffer

        int readInt = ras.read();

        assertEquals(readInt, writeInt, "wrong int read");

        expectedEvents.add(IOEvent.createFileReadEvent(1, tmp));

        byte[] readBuffer = new byte [writeBuffer.length];

        int size = ras.read(readBuffer);

        verifyBufferEquals(readBuffer, writeBuffer);

        expectedEvents.add(IOEvent.createFileReadEvent(readBuffer.length, tmp));

        // Read beyond EOF

        readInt = ras.read();

        assertEquals(-1, readInt, "wrong read after EOF");

        expectedEvents.add(IOEvent.createFileReadEvent(-1, tmp));

        // Seek to beginning and verify we can read after EOF.

        ras.seek(0);

        readInt = ras.read();

        assertEquals(readInt, writeInt, "wrong int read after seek(0)");

        expectedEvents.add(IOEvent.createFileReadEvent(1, tmp));

        // seek beyond EOF and verify we get EOF when reading.

        ras.seek(10);

        readInt = ras.read();

        assertEquals(-1, readInt, "wrong read after seek beyond EOF");

        expectedEvents.add(IOEvent.createFileReadEvent(-1, tmp));

        // Read partial buffer.

        int partialSize = writeBuffer.length - 2;

        ras.seek(ras.length()-partialSize);

        size = ras.read(readBuffer);

        assertEquals(size, partialSize, "Wrong size partial buffer read");

        expectedEvents.add(IOEvent.createFileReadEvent(size, tmp));

        ras.close();

        recording.stop();

        List<RecordedEvent> events = Events.fromRecording(recording);

        IOHelper.verifyEqualsInOrder(events, expectedEvents);

    }

    private static void verifyBufferEquals(byte[] a, byte[] b) {

        assertEquals(a.length, b.length, "Wrong buffer size");

        for (int i = 0; i < a.length; ++i) {

            assertEquals(a[i], b[i], "Wrong buffer content at pos " + i);

        }

    }

}