Java ByteBuffer Size mapByteBuffer(File cachedFile, int cacheFileSize)

Description

map Byte Buffer

License

Open Source License

Declaration

public static ByteBuffer mapByteBuffer(File cachedFile, int cacheFileSize) throws IOException 

Method Source Code

//package com.java2s;
/*/*from   ww w. ja  va 2 s  .  co m*/
 * Copyright (C) 2010 Stephen Tigner
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * This program 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 for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 * 02111-1307, USA.
 */

import java.io.*;
import java.nio.ByteBuffer;

import java.nio.channels.FileChannel;

public class Main {
    public static ByteBuffer mapByteBuffer(File cachedFile, int cacheFileSize) throws IOException {
        ByteBuffer byteBufferPositions = null;

        if (cacheFileSize > 1024) // don't cache tiny files
            try {
                if (cachedFile.canRead() && cachedFile.length() == cacheFileSize) {
                    RandomAccessFile raf = new RandomAccessFile(cachedFile, "r");
                    byteBufferPositions = raf.getChannel().map(FileChannel.MapMode.READ_ONLY, 0, cacheFileSize);
                    return byteBufferPositions;
                }

                if (cachedFile.exists())
                    cachedFile.delete();
                cachedFile.getParentFile().mkdirs();
                cachedFile.createNewFile();
                if (cachedFile.canWrite()) {
                    RandomAccessFile raf = new RandomAccessFile(cachedFile, "rw");
                    byteBufferPositions = raf.getChannel().map(FileChannel.MapMode.READ_WRITE, 0, cacheFileSize);
                    return byteBufferPositions;
                }
            } catch (Exception e) {
            }

        byteBufferPositions = ByteBuffer.allocate(cacheFileSize); //int[number_of_statesl];
        return byteBufferPositions;
    }
}

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7. markDifferencesWithBoxes(final BufferedImage image, final Point[] pixels, final int markingSizeX, final int markingSizeY)
8. maybeGrow(List l, int size)
9. needsThumbnail(BufferedImage image, int newSize)