Java Socket编程基础知识 (3)

　　 设计原理： 

　　 服务器端接受客户端的连接请求，同时启动一个线程处理这个连接，线程不停的读取客户端输入，然后把输入加入队列中，等候处理。在线程启动的同时将线程加入队列中，以便在需要的时候定位和取出。 

　　 ｛源码｝ 


import java.io.*; 
import java.net.*; 
import java.util.*; 
import java.lang.*; 

public class Server extends ServerSocket 
{ 
private static ArrayList User_List = new ArrayList(); 
private static ArrayList Threader = new ArrayList(); 
private static LinkedList Message_Array = new LinkedList(); 
private static int Thread_Counter = 0; 
private static boolean isClear = true; 
protected static final int SERVER_PORT = 10000; 
protected FileOutputStream LOG_FILE = new FileOutputStream("d:/connect.log", true); 

public Server() throws FileNotFoundException, IOException 
{ 
super(SERVER_PORT); 
new Broadcast(); 

//append connection log 
Calendar now = Calendar.getInstance(); 
String str = "[" + now.getTime().toString() + "] Accepted a connection/015/012"; 
byte[] tmp = str.getBytes(); 
LOG_FILE.write(tmp); 

try 
{ 
while (true) 
{ 
Socket socket = accept(); 
new CreateServerThread(socket); 
} 
} 
finally 
{ 
close(); 
} 
} 

public static void main(String[] args) throws IOException 
{ 
new Server(); 
} 

//--- Broadcast 
class Broadcast extends Thread 
{ 
public Broadcast() 
{ 
start(); 
} 

public void run() 
{ 
while (true) 
{ 
if (!isClear) 
{ 
String tmp = (String)Message_Array.getFirst(); 

for (int i = 0; i < Threader.size(); i++) 
{ 
CreateServerThread client = (CreateServerThread)Threader.get(i); 
client.sendMessage(tmp); 
} 

Message_Array.removeFirst(); 
isClear = Message_Array.size() > 0 ? false : true; 
} 
} 
} 
} 

//--- CreateServerThread 
class CreateServerThread extends Thread 
{ 
private Socket client; 
private BufferedReader in; 
private PrintWriter out; 
private String Username; 

public CreateServerThread(Socket s) throws IOException 
{ 
client = s; 
in = new BufferedReader(new InputStreamReader(client.getInputStream())); 
out = new PrintWriter(client.getOutputStream(), true); 
out.println("--- Welcome to this chatroom ---"); 
out.println("Input your nickname:"); 
start(); 
} 

public void sendMessage(String msg) 
{ 
out.println(msg); 
} 

public void run() 
{ 
try 
{ 
int flag = 0; 
Thread_Counter++; 
String line = in.readLine(); 

while (!line.equals("bye")) 
{ 
if (line.equals("l")) 
{ 
out.println(listOnlineUsers()); 
line = in.readLine(); 
continue; 
} 

if (flag++ == 0) 
{ 
Username = line; 
User_List.add(Username); 
out.println(listOnlineUsers()); 
Threader.add(this); 
pushMessage("[< " + Username + " come on in >]"); 
} 
else 
{ 
pushMessage("<" + Username + ">" + line); 
} 

line = in.readLine(); 
} 

out.println("--- See you, bye! ---"); 
client.close(); 
} 
catch (IOException e) 
{} 
finally 
{ 
try 
{ 
client.close(); 
} 
catch (IOException e) 
{} 

Thread_Counter--; 
Threader.remove(this); 
User_List.remove(Username); 
pushMessage("[< " + Username + " left>]"); 
} 
} 


private String listOnlineUsers() 
{ 
String s ="-+- Online list -+-/015/012"; 

for (int i = 0; i < User_List.size(); i++) 
{ 
s += "[" + User_List.get(i) + "]/015/012"; 
} 

s += "-+---------------------+-"; 
return s; 
} 

private void pushMessage(String msg) 
{ 
Message_Array.addLast(msg); 
isClear = false; 
} 
} 
}