Telnet Applet

©1996 Bret Dahlgren

Parameters

• Host is the name of the internet host or the IP address that you want to connect to.
  
• The port for most telnet daemons is 23.
  
• The emulation must match an Emulation.class subclass in the Telnet.class directory. VT100 is the standard. Right now it's the same as ANSI. Let me know if it doesn't work for you. The emulation code can be loaded on the fly.
  
• NEW - fields parameter for removing Host, Port, and Emulation fields from applet. If fields = "OFF" these fields will not show up.
  

Known bugs

• Scrollup in ANSI does not scroll all the characters up and occasionally leaves stray characters.
  

Restrictions

• For Netscape Navigator, the only valid host is the host the code is residing on. Sun's Appletviewer is unrestricted and can connect anywhere.
  

The source

• Telnet.java - source of the main class. Based on dummy telnet code written by Jamie Cameron (jameson@ncb.gov.sg)
• Emulation.java - source of the abstract class for emulation subclasses.
• ANSI.java - source of the ANSI Emulation subclass.
• VT100.java - source of the VT100 Emulation subclass.

For non-commercial use I have three requests:

1. (c)1996 Bret Dahlgren appears on the page.
2. There is a pointer to the original page of the
   code (http://bret.dahlgren.com/telnet/) so users
   can see the code for themselves.
3. I am notified of the URL.

Version 0.94  - Multitude of changes in IAC, new fields parameter,
                scroll regions and more bug fixes.  All source files have
                changed.  See each one for specific changes.
Version 0.93  - Now working on cleaning up platform dependent bugs.
                Telnet - Windows NT and BSD/OS think the width of the
                characters are twice what they really are. Cut them in
                half. If this bug is fixed the change will be bypassed.
                NT was acting strangely by not showing the last two
                characters on the screen.  I put in a
                System.out.println("") and the problem went away.  This
                is a stop gap measure and will be taken out when a
                real solution is found or the bug is fixed.
                I was able to fix up the top of the screen for BSD/OS
                and Windows NT so all the buttons appear now.  Please
                send me screen shots of your telnet with your os.name
                if you can't see the connect and disconnect buttons. 

                ANSI/VT100 - bug when cursor positioning went out
                of range it didn't verify and would cause an array out-
                of-bounds exception.  Now it's constrained to the array
                of the screen.
Version 0.92  - ANSI/VT100 - Now completely clear parameters, sometimes
                screwed up ESC [H because the second parameter was invalid.
                Now store background/foreground for each character because the
                cursor screwed it up occasionally.
                Now handle CR and LF correctly.
Version 0.91a - ANSI.class - Fixed Telnet commands echoing to screen.
                Now will print characters above 127.
                Added ESC [? pass over for VT100 codes.
                Copied over to make base VT100.class 
Version 0.91a - Telnet IAC Authentication Option code handled.  Expect a few of
                these changes while other people try it with their particular
                telnet daemons.
Version 0.91  - Fixed the period key problem. Kluged it by catching it on keyUp.
Version 0.90  - Initial release.

Feedback: Please send me your comments and requests to bret@dahlgren.com.

This file was last updated April 27, 1996