commons-net 的用法.

注意要点:参考官方的demo,而不要采用大多数网上的demo,访问交换机会在登录那块堵塞.所以要实现Runnable,如果要显示反馈的话实现TelnetNotificationHandler 接口.

package com.sobey.telnet.service;

import java.io.IOException;
import java.io.InputStream;
import java.io.PrintStream;

import org.apache.commons.net.telnet.EchoOptionHandler;
import org.apache.commons.net.telnet.SuppressGAOptionHandler;
import org.apache.commons.net.telnet.TelnetClient;
import org.apache.commons.net.telnet.TelnetNotificationHandler;
import org.apache.commons.net.telnet.TerminalTypeOptionHandler;
import org.springframework.stereotype.Service;

@Service
public class TelnetService implements Runnable, TelnetNotificationHandler {

	public TelnetService() {
		super();
	}

	private static TelnetClient tc = null;
	private InputStream in;
	private PrintStream out;

	@Override
	public void receivedNegotiation(int negotiation_code, int option_code) {
		String command = null;
		if (negotiation_code == TelnetNotificationHandler.RECEIVED_DO) {
			command = "DO";
		} else if (negotiation_code == TelnetNotificationHandler.RECEIVED_DONT) {
			command = "DONT";
		} else if (negotiation_code == TelnetNotificationHandler.RECEIVED_WILL) {
			command = "WILL";
		} else if (negotiation_code == TelnetNotificationHandler.RECEIVED_WONT) {
			command = "WONT";
		}
		System.out.println("Received " + command + " for option code " + option_code);
	}

	public void execCommand(String ip, String username, String password, String command) {
		Thread t = new Thread(new TelnetService(ip, 23, username, password, command));
		t.start();
	}

	@Override
	public void run() {
		InputStream instr = tc.getInputStream();
		try {
			byte[] buff = new byte[1024];
			int ret_read = 0;
			do {
				ret_read = instr.read(buff);
				if (ret_read > 0) {
					System.out.print(new String(buff, 0, ret_read));
				}
			} while (ret_read >= 0);
		} catch (Exception e) {
			System.err.println("Exception while reading socket:" + e.getMessage());
		}
		try {
			tc.disconnect();
		} catch (Exception e) {
			System.err.println("Exception while closing telnet:" + e.getMessage());
		}
	}

	public TelnetService(String ip, int port, String username, String password, String command) {
		if (intconnect(ip, port)) {
			write(username);
			write(password);
			write(command);
		}
	}

	private void write(String command) {
		try {
			out.println(command);
			out.flush();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	private boolean intconnect(String ip, int port) {
		try {
			tc = new TelnetClient();
			TerminalTypeOptionHandler ttopt = new TerminalTypeOptionHandler("VT100", false, false, true, false);
			EchoOptionHandler echoopt = new EchoOptionHandler(true, false, true, false);
			SuppressGAOptionHandler gaopt = new SuppressGAOptionHandler(true, true, true, true);

			tc.addOptionHandler(ttopt);
			tc.addOptionHandler(echoopt);
			tc.addOptionHandler(gaopt);
			tc.connect(ip, port);
			in = tc.getInputStream();
			out = new PrintStream(tc.getOutputStream());
			return true;
		} catch (Exception e) {
			e.printStackTrace();
			try {
				tc.disconnect();
			} catch (IOException e1) {
				e1.printStackTrace();
			}
			return false;
		}
	}

}