Notes on using Java applets in browsers

General Instructions for enabling Java

  • Mozilla and Netscape 4.x: Edit -> Preferences -> Advanced and then check "Enable Java"
  • Internet Explorer 5.5 and 6.0:
    • Windows and Linux: Tools -> Internet Options -> Advanced and then select either the "Microsoft VM" or the "Java Plug-in"
      then do....
      Tools -> Internet Options -> Security -> Custom Level... then scroll down to make sure Java is enabled
    • Mac: On the "task bar", Internet Explorer -> Edit -> Preferences -> Web browser -> Java and then Under "Java options", check the "Enable Java (Apple MRJ)" box
  • Opera: File -> Preferences -> Multimedia and then check "Enable Java"

What to do if you have a problem

The first thing to do is to find the "Java Console" and open it. This may be located in the "View" menu, the "Tools" menu, or the "Web Development" menu, depending on your browser. If you are using the Java Plug-in, then you can also launch the Java Console by clicking (sometimes right-clicking) on the Java icon when you try to run the applet.

If you have error messages in the Java Console, these will be very helpful to the software support people, and you should consider sending the text in the Java Console to them.

General Information on the Java Runtime

Try to use the Sun Java Plug-in whenever possible.

  • Windows
    • Netscape 4.x - no known problems - comes with Java version 1.1.5, and cannot be changed (does not allow for 'swing' components).
    • Netscape 6 and 7 - must get the Java Runtime Plug-in from Sun.
    • Mozilla 1.x - no known problems; must install Java Runtime plug-in (as above).
    • Internet Explorer 6.x - install the Java Runtime Plug-in (version 1.3.1 or 1.4.2+) -- there was a time where Microsoft was not packaging their own Java (some legal battle) so if you have that version, you'll need to use the Plug-in.
    • Internet Explorer 5.x - no known problems; may use the Microsoft VM or install the Java Runtime Plugin (version 1.3.1 or 1.4.2+).
    • Opera 6.x - must install the Java Plug-in (as above) or download the Opera version with Java (recommended).
  • Mac OS9
    • Netscape 4.x - do not use!!
    • Netscape 6 and 7 - install Apple Classic MRJ version 2.2.5 or later and enable Java. Some say it is better to install the MRJ before installing Netscape.
    • Internet Explorer - enable Java and choose the Apple MRJ
  • Mac OSX
    Comes with Java installed. Please be sure you have the latest update from Apple.

    The beta versions of the Safari browser do not re-draw images correctly (line drawings look like they don't get "erased" properly) and do not layout some widgets (buttons, etc). While newer versions of Safari seem to have corrected some of these issues, if you encounter difficulties, you should use a different browser.

    If you are using IE, Mozilla or Opera you might check the JVM version they use. If it is 1.3.1, you might visit this site and try the plug-in from there (which is designed to enable Java 1.4.2 with these browsers).

  • Linux
    • Netscape 4.x - usually will only allow you to use the built-in runtime, version 1.1.5. This does not have "swing" components (modern buttons, menus, etc).
    • Netscape 6 and 7 - install Java Plug-in (version 1.3.1 or 1.4.2+) and enable Java
    • Mozilla 1.x - install the Java plug-in (version 1.3.1 or 1.4.2+) and enable Java.
    • Opera 6 - unknown
  • Solaris (Unix) on Sparc
  • IBM AIX
  • SGI Irix

Source: http://www.ssec.wisc.edu/~tomw/jvm.html