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I've got a simple web server that uses an infinite loop to accept connections. This works fine, but now I want to be able to stop the server with a command from System.in to the server. Any ideas how to do this. Everytime I try to read from System.in if there is nothing there it just blocks. Here's the relevant code:
Code:
public static void main(String args[])throws Exception{
String clientRequest = null;
/* get the port number as the first argument */
ServerSocket welcomeSocket = new ServerSocket(Integer.parseInt(args[0]));
Socket connectionSocket;
BufferedReader inFromClient;
DataOutputStream outToClient;
BufferedReader control = new BufferedReader(
new InputStreamReader(System.in));
while(true){
/* loop continuously accepting connections */
connectionSocket = welcomeSocket.accept();
/* create a BufferedReader object to read input */
inFromClient =
new BufferedReader(new InputStreamReader(
connectionSocket.getInputStream()));
/* create a DatatOutputStream object to write data */
outToClient =
new DataOutputStream(
connectionSocket.getOutputStream());
/* get the request from the client */
clientRequest = inFromClient.readLine();
/* create a Webserver object so we can manipulate the request */
WebServer app = new WebServer();
/* process the request */
app.processRequest(connectionSocket, inFromClient, outToClient, clientRequest);
/* close the socket after the response is sent */
connectionSocket.close();
clientRequest = null;
}
}
}
You could add a thread that's dedicated to gathering the input so the server thread can go about with it's business
Code:
import java.net.*;
import java.io.*;
public class server {
//vars are out here so threads other than main thread can access them
static BufferedReader control = new BufferedReader(
new InputStreamReader(System.in));
public static void main(String args[])throws Exception{
Thread controlThread = new Thread(new Runnable() {
public void run() {
while (true) {
try {
String input = control.readLine();
} catch (IOException e){}
//blah blah, decide whether to exit or not
//if (timeToExit)
//cleanup
System.exit(0);
}
}
});
controlThread.start();
String clientRequest = null;
/* get the port number as the first argument */
ServerSocketwelcomeSocket = new ServerSocket(Integer.parseInt(args[0]));
Socket connectionSocket;
BufferedReader inFromClient;
DataOutputStream outToClient;
while(true){
/* loop continuously accepting connections */
connectionSocket = welcomeSocket.accept();
/* create a BufferedReader object to read input */
inFromClient =
new BufferedReader(new InputStreamReader(
connectionSocket.getInputStream()));
/* create a DatatOutputStream object to write data */
outToClient =
new DataOutputStream(
connectionSocket.getOutputStream());
/* get the request from the client */
clientRequest = inFromClient.readLine();
/* create a Webserver object so we can manipulate the request */
WebServer app = new WebServer();
/* process the request */
app.processRequest(connectionSocket, inFromClient, outToClient, clientRequest);
/* close the socket after the response is sent */
connectionSocket.close();
clientRequest = null;
}
}
}
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