jdk/src/share/classes/sun/misc/JavaNioAccess.java
author coffeys
Thu, 11 Aug 2011 12:40:24 +0100
changeset 10325 b72c20cd583a
parent 5506 202f599c92aa
permissions -rw-r--r--
7047325: Internal API to improve management of direct buffers Reviewed-by: alanb, mduigou

/*
 * Copyright (c) 2007, 2011, 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,
 * 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.
 */

package sun.misc;

import java.nio.Buffer;
import java.nio.ByteBuffer;

public interface JavaNioAccess {
    /**
     * Provides access to information on buffer usage.
     */
    interface BufferPool {
        String getName();
        long getCount();
        long getTotalCapacity();
        long getMemoryUsed();
    }
    BufferPool getDirectBufferPool();

    /**
     * Constructs a direct ByteBuffer referring to the block of memory starting
     * at the given memory address and and extending {@code cap} bytes.
     * The {@code ob} parameter is an arbitrary object that is attached
     * to the resulting buffer.
     */
    ByteBuffer newDirectByteBuffer(long addr, int cap, Object ob);

    /**
     * Truncates a buffer by changing its capacity to 0.
     */
    void truncate(Buffer buf);

}