hotspot/test/runtime/Unsafe/GetPutDouble.java

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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
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 * 2 along with this work; if not, write to the Free Software Foundation,
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/*
 * @test
 * @summary Verify behaviour of Unsafe.get/putDouble
 * @library /test/lib
 * @modules java.base/jdk.internal.misc
 *          java.management
 * @run main GetPutDouble
 */

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

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

        long offset = unsafe.objectFieldOffset(field);
        assertEquals(-1.0, unsafe.getDouble(t, offset));
        unsafe.putDouble(t, offset, 0.0);
        assertEquals(0.0, unsafe.getDouble(t, offset));

        long address = unsafe.allocateMemory(8);
        unsafe.putDouble(address, 1.0);
        assertEquals(1.0, unsafe.getDouble(address));
        unsafe.freeMemory(address);

        double arrayDouble[] = { -1.0, 0.0, 1.0, 2.0 };
        int scale = unsafe.arrayIndexScale(arrayDouble.getClass());
        offset = unsafe.arrayBaseOffset(arrayDouble.getClass());
        for (int i = 0; i < arrayDouble.length; i++) {
            assertEquals(unsafe.getDouble(arrayDouble, offset), arrayDouble[i]);
            offset += scale;
        }
    }

    static class Test {
        public double d = -1.0;
    }
}