Java 使用NIO进行快速的文件拷贝的代码详解编程语言

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();  
    }  
    }  
}