I hit a page that had a Java applet and got the following “Missing Plugin” message.
Basically, my browser – firefox was unable to locate a Java Plugin needed to execute the applet on the page.
It also gave me an option to “install the missing plugin” which essentially involved downloading a complete JRE which would take time.
However, since I already had the latest JRE installed on my system, this is how I went about configuring firefox to use the same.
1. View the contents of the firefox plugins folder to look for existing/older Java plugins (if any)
abhi@abhiltlnx(~)$ type firefox firefox is /usr/bin/firefox abhi@abhiltlnx(~)$ ls -ll /usr/bin/firefox lrwxrwxrwx 1 root root 25 2008-02-08 03:05 /usr/bin/firefox -> ../lib/firefox/firefox.sh abhi@abhiltlnx(~)$ ls -lth /usr/lib/firefox/ total 12M drwxr-xr-x 2 root root 4.0K 2008-02-08 03:05 icons drwxr-xr-x 2 root root 4.0K 2008-02-08 03:05 plugins drwxr-xr-x 6 root root 4.0K 2008-02-08 03:05 res drwxr-xr-x 2 root root 4.0K 2008-02-08 03:05 searchplugins drwxr-xr-x 2 root root 4.0K 2008-02-08 03:05 greprefs drwxr-xr-x 3 root root 4.0K 2008-02-08 03:05 chrome drwxr-xr-x 2 root root 4.0K 2008-02-08 03:05 components drwxr-xr-x 5 root root 4.0K 2008-02-08 03:05 defaults drwxr-xr-x 2 root root 4.0K 2008-02-08 03:05 dictionaries drwxr-xr-x 5 root root 4.0K 2008-02-08 03:05 extensions -rwxr-xr-x 1 root root 9.4M 2007-09-25 00:22 firefox-bin -rwxr-xr-x 1 root root 14K 2007-09-25 00:22 mozilla-xremote-client -rwxr-xr-x 1 root root 107K 2007-09-25 00:22 libxpcom_compat.so -rwxr-xr-x 1 root root 798K 2007-09-25 00:22 libxpcom_core.so -rwxr-xr-x 1 root root 9.6K 2007-09-25 00:22 libxpcom.so -rwxr-xr-x 1 root root 14K 2007-09-25 00:22 libxpistub.so -rwxr-xr-x 1 root root 62K 2007-09-25 00:22 updater -rwxr-xr-x 1 root root 621K 2007-09-25 00:22 libmozjs.so -rwxr-xr-x 1 root root 22K 2007-09-25 00:22 xpicleanup -rw-r--r-- 1 root root 158 2007-09-25 00:22 browserconfig.properties -rwxr-xr-x 1 root root 6.1K 2007-09-25 00:22 firefox.sh -rw-r--r-- 1 root root 177 2007-09-25 00:19 readme.txt -rwxr-xr-x 1 root root 11K 2007-09-25 00:19 run-mozilla.sh -rw-r--r-- 1 root root 145 2007-09-25 00:19 updater.ini abhi@abhiltlnx(~)$ ls -lth /usr/lib/firefox/plugins/ total 24K -rwxr-xr-x 1 root root 22K 2007-09-25 00:22 libnullplugin.so
2. Locate the Java plugin library file in the installed JDK/JRE
The java plugin file will be – $JRE_HOME/jre/plugin/i386/ns7/libjavaplugin_oji.so
abhi@abhiltlnx(~)$ type java java is hashed (/usr/bin/java) abhi@abhiltlnx(~)$ ls -ll /usr/bin/java lrwxrwxrwx 1 root root 30 2008-02-17 06:22 /usr/bin/java -> /opt/java/jdk1.6.0_04/bin/java abhi@abhiltlnx(~)$ cd /opt/java/jdk1.6.0_04/ abhi@abhiltlnx(/opt/java/jdk1.6.0_04)$ ls -lth jre/plugin/i386/ns7/ total 140K -rwxr-xr-x 1 root root 134K 2007-12-14 15:04 libjavaplugin_oji.so abhi@abhiltlnx(/opt/java/jdk1.6.0_04)$
3. Create a soft/symbolic link to the java plugin file in the firefox plugins folder.
Note: root access needed… use sudo.
abhi@abhiltlnx(/opt/java/jdk1.6.0_04)$ sudo ln -s jre/plugin/i386/ns7/libjavaplugin_oji.so /usr/lib/firefox/plugins/ root's password: abhi@abhiltlnx(/opt/java/jdk1.6.0_04)$ ls -lth /usr/lib/firefox/plugins/ total 28K lrwxrwxrwx 1 root root 62 2008-02-26 00:54 libjavaplugin_oji.so -> /opt/java/jdk1.6.0_04/jre/plugin/i386/ns7/libjavaplugin_oji.so -rwxr-xr-x 1 root root 22K 2007-09-25 00:22 libnullplugin.so abhi@abhiltlnx(/opt/java/jdk1.6.0_04)$
Exit and restart firefox. You should be able to view the applet on the page.
If you have any issues, make sure that Java has been enabled in the content tab of the firefox preferences dialog (Edit -> Preferences -> Content)
4. View Java Console
In order to view any System.out or System.err messages from the applet, configure the Java Control Panel
abhi@abhiltlnx(/opt/java/jdk1.6.0_04/bin)$ javaws -viewer & [1] 14233 abhi@abhiltlnx(/opt/java/jdk1.6.0_04/bin)$
Restart firefox and now when an applet gets executed, you’ll view the Java Console with all the messages.
Resources:
Java SE6 Release Notes: Manual Installation and Registration of Linux Plugin
How To use Java with Firefox on 64-bit openSuSE 10.3
To learn more:
- About Java Applets –
Applets lesson from Java Tutorials - About Java Plugins –
Java Plugin Guide