src/jdk.nio.mapmode/share/classes/jdk/nio/mapmode/ExtendedMapMode.java
author adinn
Tue, 20 Aug 2019 10:11:53 +0100
changeset 57804 9b7b9f16dfd9
permissions -rw-r--r--
8224974: Implement JEP 352 Summary: Non-Volatile Mapped Byte Buffers Reviewed-by: alanb, kvn, bpb, gromero, darcy, shade, bulasevich, dchuyko

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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package jdk.nio.mapmode;

import java.nio.channels.FileChannel.MapMode;

/**
 * JDK-specific map modes.
 *
 * @since 14
 * @see java.nio.channels.FileChannel#map
 */
public class ExtendedMapMode {
    private ExtendedMapMode() { }

    /**
     * File mapping mode for a read-only mapping of a file backed by
     * non-volatile RAM.
     *
     * <p> The {@linkplain FileChannel#map map} method throws
     * {@linkplain UnsupportedOperationException} when this map mode
     * is used on an implementation that does not support it.
     *
     * @implNote On Linux, the {@code MAP_SYNC} and {@code
     * MAP_SHARED_VALIDATE} flags are specified to {@code mmap} when
     * mapping the file into memory.
     */
    public static final MapMode READ_ONLY_SYNC = jdk.internal.misc.ExtendedMapMode.READ_ONLY_SYNC;

    /**
     * File mapping mode for a read-write mapping of a file backed by
     * non-volatile RAM. {@linkplain MappedByteBufefr#force force}
     * operations on a buffer created with this mode will be performed
     * using cache line writeback rather than proceeding via a file
     * device flush.
     *
     * <p> The {@linkplain FileChannel#map map} method throws
     * {@linkplain UnsupportedOperationException} when this map mode
     * is used on an implementation that does not support it.
     *
     * @implNote On Linux, the {@code MAP_SYNC} and {@code
     * MAP_SHARED_VALIDATE} flags are specified to {@code mmap} when
     * mapping the file into memory.
     */
    public static final MapMode READ_WRITE_SYNC = jdk.internal.misc.ExtendedMapMode.READ_WRITE_SYNC;

}