import org.apache.commons.net.telnet.SuppressGAOptionHandler; //导入依赖的package包/类
@Test
public void testRejectSGA() throws Exception {
  final AtomicReference<Boolean> serverValue = new AtomicReference<>();
  SuppressGAOptionHandler optionHandler = new SuppressGAOptionHandler(false, false, false, false);
  testOptionValue(() -> new TelnetHandler() {
    @Override
    protected void onOpen(TelnetConnection conn) {
      conn.writeWillOption(Option.SGA);
    }
    @Override
    protected void onSGA(boolean sga) {
      serverValue.set(sga);
      testComplete();
    }
  }, optionHandler);
  assertEquals(false, serverValue.get());
  assertEquals(false, optionHandler.getAcceptRemote());
}
 

import org.apache.commons.net.telnet.SuppressGAOptionHandler; //导入依赖的package包/类
@Test
public void testAcceptSGA() throws Exception {
  final AtomicReference<Boolean> serverValue = new AtomicReference<>();
  SuppressGAOptionHandler optionHandler = new SuppressGAOptionHandler(false, false, false, true);
  testOptionValue(() -> new TelnetHandler() {
    @Override
    protected void onOpen(TelnetConnection conn) {
      conn.writeWillOption(Option.SGA);
    }
    @Override
    protected void onSGA(boolean sga) {
      serverValue.set(sga);
      testComplete();
    }
  }, optionHandler);
  assertEquals(true, serverValue.get());
  assertEquals(true, optionHandler.getAcceptRemote());
}
 

import org.apache.commons.net.telnet.SuppressGAOptionHandler; //导入依赖的package包/类
public void open(String host, int port) throws IOException {
    // Synchronized block prevents listener thread from attempting to read input before we're ready.
    synchronized (this.charBuffer) {
        this.telnetClient.connect(host, port);
        this.telnetClient.setKeepAlive(true);

        if (this.suppressGAOptionHandler == null) {
            // Only do this once.
            this.suppressGAOptionHandler = new SuppressGAOptionHandler(true, true, true, true);

            try {
                this.telnetClient.addOptionHandler(this.suppressGAOptionHandler);
            } catch (InvalidTelnetOptionException e) {
                // Should never happen. Wrap it inside IOException so as not to declare another throwable.
                throw new IOException(e);
            }
        }

        this.reader = new BufferedReader(new InputStreamReader(this.telnetClient.getInputStream()));
        this.outstream = new PrintStream(this.telnetClient.getOutputStream());
    }
}
 

import org.apache.commons.net.telnet.SuppressGAOptionHandler; //导入依赖的package包/类
public void connect() throws TransportException {
	logger.info("Telnet Transport trying to connect...");

	// Create a new telnet client
	telnetClient = new TelnetClient();

	// VT100 terminal type will be subnegotiated
	TerminalTypeOptionHandler ttopt = new TerminalTypeOptionHandler("VT100", false, false, true, false);
	// WILL SUPPRESS-GA, DO SUPPRESS-GA options
	SuppressGAOptionHandler gaopt = new SuppressGAOptionHandler(true, true, true, true);
	// WON'T ECHO, DON'T ECHO
	EchoOptionHandler echoopt = new EchoOptionHandler();

	try {
		// set telnet client options
		telnetClient.addOptionHandler(ttopt);
		telnetClient.addOptionHandler(gaopt);
		telnetClient.addOptionHandler(echoopt);

		// connect
		telnetClient.connect(host, Integer.parseInt(port));

		// set the read timeout
		telnetClient.setSoTimeout(READ_TIMEOUT);

		// Initialize the print writer
		outPrint = new PrintWriter(telnetClient.getOutputStream(), true);
	} catch (Exception e) {
		e.printStackTrace();
		throw new TransportException("Could not connect, unable to open telnet session " + e.getMessage());
	}
}
 

import org.apache.commons.net.telnet.SuppressGAOptionHandler; //导入依赖的package包/类
public void connect() throws TransportException {
	logger.info("Telnet Transport trying to connect...");
	
	//Create a new telnet client
	telnetClient = new TelnetClient();

	//VT100 terminal type will be subnegotiated
       TerminalTypeOptionHandler ttopt = new TerminalTypeOptionHandler("VT100", false, false, true, false);
       //WILL SUPPRESS-GA, DO SUPPRESS-GA options
       SuppressGAOptionHandler gaopt = new SuppressGAOptionHandler(true, true, true, true);
       //WON'T ECHO, DON'T ECHO
       EchoOptionHandler echoopt = new EchoOptionHandler();
       
       try{
       	//set telnet client options
       	telnetClient.addOptionHandler(ttopt);
       	telnetClient.addOptionHandler(gaopt);
       	telnetClient.addOptionHandler(echoopt);

       	//connect
       	telnetClient.connect(host, Integer.parseInt(port));
       	
       	//set the read timeout
       	telnetClient.setSoTimeout(READ_TIMEOUT);
       	
       	//Initialize the print writer
       	outPrint=new PrintWriter(telnetClient.getOutputStream(),true);
       }catch(Exception e){
       	e.printStackTrace();
		throw new TransportException("Could not connect, unable to open telnet session "+ e.getMessage());
       }
}