A good memory is better than a bad pen. 5-java Quick File Copy

If you use a file system such as Luncene or Hadoop, there are a large number of index files to be distributed, you can use ready-made distribution tools, or you can write your own program for quick file copy;

Use NIO make quick copies of files

Package com.daily;

Import Java.io.File;

Import Java.io.FileInputStream;

Import Java.io.FileOutputStream;

Import java.io.IOException;

Import Java.nio.channels.FileChannel;

/**

*nio fast file copy, maxcount=128m, copy 351M files, 11001 (MS)

 * the same file, with (*1024 * 1024x768)-(18192 * 1024x768), time-consuming (milliseconds)

* @author Fan Fangming

*/

public class Easyfastcopy {

Publicvoid fileCopy (string in, string out) throws IOException {

Filechannelinchannel = new FileInputStream (new File (in)). Getchannel ();

Filechanneloutchannel = new FileOutputStream (new File). Getchannel ();

try{

            // If the memory is large, this value can be expanded appropriately, and there are advantages to copying large files .

Intmaxcount = (128 * 1024 * 1024);

Intmaxcount = (8 * 1024 * 1024);

int MaxCount = (64 * 1024 * 1024)-(32 *1024);

Longsize = Inchannel.size ();

longposition = 0;

while (position < size) {

position+= Inchannel

. TransferTo (Position,maxcount, Outchannel);

}

}finally {

if (Inchannel! = null) {

Inchannel.close ();

}

if (Outchannel! = null) {

Outchannel.close ();

}

}

}

publicstatic void Main (string[] args) throws Exception {

Longstart = System.currenttimemillis ();

Easyfastcopycopy = new Easyfastcopy ();

Copy.filecopy ("D:/ffm83/big.rar", "D:/ffm83/temp/big.rar");

Longend = System.currenttimemillis ();

System.out.println (" Fast File copy time:" + (End-start) + "( ms)");

}

}

A good memory is better than a bad pen. 5-java Quick File Copy