四种复制文件的方法

尽管Java提供了一个类ava.io.File用于文件的操作，但是该类不包括文件的复制操作。但是，复制文件是平时文件操作中一个重要的功能，本文给出四种比较流行的文件复制方法。

1. 使用FileStream

private static void copyFileUsingFileStreams(File source, File dest) throws IOException {
    InputStream input = null;
    OutputStream output = null;
    try {
        input = new FileInputStream(source);
        output = new FileOutputStream(dest);
        byte[] buf = new byte[1024];
        int bytesRead;
        while ((bytesRead = input.read(buf)) > 0) {
            output.write(buf, 0, bytesRead);
        }
    } finally {
        input.close();
        output.close();
    }
}

 

2. 使用FileChannel java.nio.channels.FileChannel

private static void copyFileUsingFileChannels(File source, File dest) throws IOException {
    FileChannel inputChannel = null;
    FileChannel outputChannel = null;
    try {
        inputChannel = new FileInputStream(source).getChannel();
        outputChannel = new FileOutputStream(dest).getChannel();
        outputChannel.transferFrom(inputChannel, 0, inputChannel.size());
    } finally {
        inputChannel.close();
        outputChannel.close();
    }
}

 

3. 使用Apache Commons IO

private static void copyFileUsingApacheCommonsIO(File source, File dest)
        throws IOException {
    FileUtils.copyFile(source, dest);
}

 

4. 使用Java 7 Files Files

 

private static void copyFileUsingJava7Files(File source, File dest)
        throws IOException {
    Files.copy(source.toPath(), dest.toPath());
}

 

更多的例子请参考：http://thecodesample.com/