Homeworks: problems and fixes

I am not sure which problems happen with which version of Windows in exactly which circumstances. I hope this is helpful in getting around some problems. Please accept my apologies for any unhappiness caused by my failure to identify these problems in advance.

  1. problem The Internet Explorer may download NpvA.html with the name NpvA.htm instead. fix Just use "NpvA.htm" whenever you would have used "NpvA.html".
  2. problem The Internet Explorer adds .htm to .java files. For example, it may save the file NpvA.java with the name NpvA.java.htm. fix Rename the file (easiest in DOS -- "rename NpvA.java.htm NpvA.java" -- or enable show entire file name in Windows), or, when you save the file, do not put the suffix in the dialog box (If you just leave the file name alone, it gives it its original suffix, but if you add .java yourself it adds .htm afterwards).
  3. problem The notepad wants to interpret NpvA.htm or NpvA.java as a file containing a single very long line. fix Download the file again (use the Refresh key in Internet Explorer or Reload in Netscape -- you may also have to clear the cache in IE to keep it from using a locally saved version). The problem is that DOS and Windows do not recognize all text files. Around dinner time Wed, Jan 13, 1999, I changed the one on the Web page to a text format that is compatible with Notepad and still works for the rest of the world too. (Hopefully, this is not a problem anymore.)
  4. problem Using cd in DOS to get to the working directory may not find a directory that is there. fix Work in a simply-named directory such as U:\dybvigs\java or C:\java\0. Usually this problem will happen if the directory name has spaces or other features not available originally in DOS filenames. This is because when the operating system was extended to use more general file names it was done in a clumsy way.
  5. problem You compile your java applet with the changes but when you view the applet you see my original applet. fix Several possibilities: (1) Internet Explorer edited the .html file without asking. Use ``save as'' and ``html only'' in your download. (2) Your compilation failed. Check for error messages when you use javac. (3) There is a logical error in your program. Unfortunately, this is pretty open-ended. It may require some detective work or asking me or a TA to fix the problem.