hotspot/test/runtime/Unsafe/GetPutByte.java
author chegar
Sat, 09 Apr 2016 23:03:39 +0100
changeset 36851 03e2f4d0a421
parent 30604 b8d532cb6420
child 38152 80e5da81fb2c
permissions -rw-r--r--
8153737: Unsupported Module Reviewed-by: alanb, mchung, psandoz

/*
 * Copyright (c) 2015, 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
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 * questions.
 */

/*
 * @test
 * @summary Verify behaviour of Unsafe.get/putByte
 * @library /testlibrary
 * @modules java.base/jdk.internal.misc
 *          java.management
 * @run main GetPutByte
 */

import java.lang.reflect.Field;
import jdk.test.lib.*;
import sun.misc.Unsafe;
import static jdk.test.lib.Asserts.*;

public class GetPutByte {
    public static void main(String args[]) throws Exception {
        Unsafe unsafe = Utils.getUnsafe();
        Test t = new Test();
        Field field = Test.class.getField("b");

        long offset = unsafe.objectFieldOffset(field);
        assertEquals((byte)0, unsafe.getByte(t, offset));
        unsafe.putByte(t, offset, (byte)1);
        assertEquals((byte)1, unsafe.getByte(t, offset));

        long address = unsafe.allocateMemory(8);
        unsafe.putByte(address, (byte)2);
        assertEquals((byte)2, unsafe.getByte(address));
        unsafe.freeMemory(address);

        byte arrayByte[] = { -1, 0, 1, 2 };
        int scale = unsafe.arrayIndexScale(arrayByte.getClass());
        offset = unsafe.arrayBaseOffset(arrayByte.getClass());
        for (int i = 0; i < arrayByte.length; i++) {
            assertEquals(unsafe.getByte(arrayByte, offset), arrayByte[i]);
            offset += scale;
        }
    }

    static class Test {
        public byte b = 0;
    }
}