import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.io.OutputStream;

import java.net.SocketException;

import org.apache.commons.net.telnet.TelnetClient;

public class Client {

    public static void main(String[] args){

        try {

            TelnetClient tc = new TelnetClient();

            tc.connect("192.168.100.8", 23);

            InputStream in = tc.getInputStream();

            OutputStream os = tc.getOutputStream();

            System.out.print(readUntil(":", in));

            writeUtil("root", os);

            System.out.print(readUntil(":", in));

            writeUtil("freewificom", os);

            System.out.print(readUntil("root@WiAC:~#", in));

            writeUtil("ls -l / ", os);

            System.out.print(readUntil("root@WiAC:~#", in));

            writeUtil("ip addr ", os);

            System.out.print(readUntil("root@WiAC:~#", in));

            writeUtil("ip route ", os);

            System.out.print(readUntil("root@WiAC:~#", in));

        } catch (SocketException e) {

            e.printStackTrace();

        } catch (IOException e) {

            e.printStackTrace();

        }

    }

    /**

     * 写入命令方法

     * @param cmd

     * @param os

     */

    public static void writeUtil(String cmd, OutputStream os){

        try {

            cmd = cmd + "\n";

            os.write(cmd.getBytes());

            os.flush();

        } catch (IOException e) {

            e.printStackTrace();

        }

    }

    /**

     * 读到指定位置,不在向下读

     * @param endFlag

     * @param in

     * @return

     */

    public static String readUntil(String endFlag, InputStream in) {

        InputStreamReader isr = new InputStreamReader(in);

        char[] charBytes = new char[1024];

        int n = 0;

        boolean flag = false;

        String str = "";

        try {

            while((n = isr.read(charBytes)) != -1){

                for(int i=0; i< n; i++){

                    char c = (char)charBytes[i];

                    str += c;

                    //当拼接的字符串以指定的字符串结尾时,不在继续读

                    if(str.endsWith(endFlag)){

                        flag = true;

                        break;

                    }

                }

                if(flag){

                    break;

                }

            }

        } catch (IOException e) {

            e.printStackTrace();

        }

        return str;

    }

}