ソケットクライアント&サーバーtimeoutを使う。

myservertimeout.java

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

public class myservertimeout {
    private static final int LISTEN_PORT = 9000;
    private static final int ACCCEPT_TIMEOUT = 5000;
    private static final int READ_TIMEOUT = 5000;

    public static void main(String[] args){
        ServerSocket ssock = null;
        Socket sock = null;
        try{
            ssock = new ServerSocket(LISTEN_PORT);
            ssock.setSoTimeout(ACCCEPT_TIMEOUT);
            sock = ssock.accept();
            sock.setSoTimeout(READ_TIMEOUT);

            Reader in = new BufferedReader(new InputStreamReader(sock.getInputStream()));
            Writer out = new BufferedWriter(new OutputStreamWriter(sock.getOutputStream()));
            StringBuilder sb = new StringBuilder(4096);

            int c;
            while ((c = in.read()) != -1){
                if(c == '.'){
                    break;
                }
                sb.append((char)c);
            }
            out.write(sb.toString());
            out.flush();

            System.out.println(sb);
        } catch (SocketTimeoutException e) {
            System.err.println("timeout");
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (sock != null) {
                    sock.close();
                }
                if (ssock != null ) {
                    ssock.close();
                }
            } catch (IOException e) {}
        }
    }
}