From http://www.snipplr.com/view/70857/java-fast-file-copy-using-nio/

Java Fast File Copy using NIO

public static void fileCopy( File in, File out ) throws IOException {
    FileChannel inChannel = new FileInputStream( in ).getChannel();
    FileChannel outChannel = new FileOutputStream( out ).getChannel();
    try {//
        inChannel.transferTo(0, inChannel.size(), outChannel); 
        // original -- apparently has trouble copying large files on Windows   
        // magic number for Windows, 64Mb - 32Kb)   
        int maxCount = (64 * 1024 * 1024) - (32 * 1024);
        long size = inChannel.size(); 
        long position = 0; 
        while ( position < size ) { 
            position += inChannel.transferTo( position, maxCount, outChannel );
        } 
    } finally {
        if ( inChannel != null ) {
            inChannel.close();
        }
        if ( outChannel != null ) {
            outChannel.close();
        }
    } 
}