Java FileChannel Copy copyfile(File infile, File outfile)

Description

copyfile

License

Apache License

Declaration

private static void copyfile(File infile, File outfile) throws IOException 

Method Source Code

//package com.java2s;
/*//from  ww  w.jav a2  s .c o m
 * Copyright 2012 Johns Hopkins University
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import java.io.File;
import java.io.IOException;

import java.io.RandomAccessFile;

import java.nio.channels.FileChannel;

public class Main {
    private static void copyfile(File infile, File outfile) throws IOException {
        FileChannel in = channel(infile, false);
        FileChannel out = channel(outfile, true);

        for (long offset = 0; offset < in.size();) {
            long n = in.transferTo(offset, in.size() - offset, out);

            if (n <= 0) {
                throw new IOException("Failed transfer to channel.");
            }

            offset += n;
        }

        out.truncate(out.position());

        in.close();
        out.close();
    }

    public static FileChannel channel(File file, boolean writeable) throws IOException {
        String opts = writeable ? "rw" : "r";
        RandomAccessFile fd = new RandomAccessFile(file, opts);
        FileChannel chan = fd.getChannel();

        return chan;
    }

    /**
     * Return size of a file or size of all files contained by a directory.
     */
    public static long size(File file) {
        if (file.isFile()) {
            return file.length();
        } else {
            long size = 0;

            for (File f : file.listFiles()) {
                size += size(f);
            }

            return size;
        }
    }
}

Related

1. copyFile(File in, File out)
2. copyFile(File in, File out)
3. copyFile(File in, File out)
4. copyFile(File in, File out)
5. copyFile(File in, File out)
6. copyFile(File inFile, File outFile)
7. copyFile(File inputFile, File outputFile)
8. copyFile(File source, File dest)
9. copyFile(File source, File dest)