急求一个WEB服务器！

[jtacm]

现要做一个基础的WEB服务器，多线程的，用HTTP1.0做，急求。
小弟刚入门不久，求各为高手大哥帮忙。

[livepdm]

ServerSocket listenSocket = new ServerSocket(6789);
while(true){
Socket connectionSocket = listenSocket.accept();
aConnSocketThread.start();
...
}

[jtacm]

import j ava.io.*;
import j ava.net.*;
import java.util.*;
class Webserver {
public static void main(String argv[]) throws Exception
{
String requestMessageLine;
String fileName;
ServerSocket listenSocket = new ServerSocket(6789);
Socket connectionSocket = listenSocket.accept();
BufferedReader inFromClient =
new BufferedReader(new InputStreamReader(
connectionSocket.get!nputStream()));
DataOutputStream outToClient =
new DataOutputStream(
connectionSocket.getOutputStream());
requestMessageLine = inFromClient.readLine();

StringTokenizer tokenizedLine =
new StringTokenizer(requestMessageLine);

if (tokenizedLine.nextToken().equals("GET")){

fileName = tokenizedLine.nextToken();

if (fileName.startsWith("/") == true )
fileName = fileName.substring(1);
File file = new File(fileName);

int numOfBytes = (int) file.length();

FileInputStream inFile = new FileInputStream (fileName);

byte[] fileInBytes = new byte[numOfBytes];

inFile.read(fileInBytes);
outToClient.writeBytes(
"HTTP/I.0 200 Document Follows\r\n");
if (fileName.endsWith(".jpg"))
outToClient.writeBytes("Content-Type:image/jpeg\r\n");
if (fileName.endsWith(".gif"))
outToClient.writeBytes("Content-Type:image/gif\r\n");
outToClient.writeBytes("Content-Length: " +
numOfBytes + "\r\n");
outToClient.writeBytes("\r\n") ;
outToClient.write(fileInBytes, 0, numOfBytes);
connectionSocket.close();
}
else System.out.println("Bad Request Message");
}
}

即把这个改成多线程的，请问怎么改啊？？