localhostの13番ポートで動作しているDaytimeサーバに接続するクライアント

DaytimeText.java

import java.net.*;
import java.io.*;
public class DaytimeText {
    boolean isOK = false;
    String host;
    Socket sock;
    public DaytimeText(String host, int port) {
        try {
            this.host = host;
            sock = new Socket(host, port);
            isOK = true;
        } catch (UnknownHostException e) {
            System.err.println("unknown host : " + host);
        } catch (NoRouteToHostException e) {
            System.err.println("unreachable : " + host);
        } catch (ConnectException e) {
            System.err.println("connect refused : " + host);
        } catch (java.io.IOException e) {
            e.printStackTrace();
        }
    }
    public void run() {
        if (! isOK) {
            System.exit(1);
        }
        try {
            BufferedReader is;
            is = new BufferedReader (new InputStreamReader (sock.getInputStream())); // ソケットの中からInputStreamを取り出している
            String s;
            while ((s = is.readLine()) != null) {
                System.out.println(host + ":" + s);
            }
            sock.close();
        } catch (java.io.IOException e) {
            e.printStackTrace();
        }
    }
}

RunDaytimeText.java

public class RunDaytimeText {
    public static void main(String[] args) {
        DaytimeText cli = new DaytimeText("localhost", 13);
        cli.run();
    }
}