install Java plugin under UbuntuFrom:http://www.googies.info/blog/15.html
Java applets have recently been used under Linux. By default, neither Firefox nor Google Chrome for Linux has a Java plugin installed. You need to install them manually.
First, make sure that you have Java installed. You can choose to install the JDK (Java Development Kit) or install the JRE separately (Java Runtime environment). The JDK is the core of the entire Java system, including JRE, a stack of Java tools, and a Java-based class library, and the JRE is a collection of environments that are required to run Java programs, including the JVM (Java Virtual Machine) standard implementation and the Java Core Class library. Here, I assume that the JRE is already installed in the/opt/java/jre1.7.0_19/directory.
Firefox
By default, Firefox-related library files are located in the/usr/lib/firefox-$VERSION/directory (you can find the library file directory through the Whereis Firefox command). Execute the following command sequentially:
cd/usr/lib/firefox-$VERSION/plugins
sudo ln-s/opt/java/jre1.6.0_19/plugin/i386/ns7/libjavaplugin_oji.so or
sudo ln-s/opt/java/jre1.6.0_19/lib/i386/libnpjp2.so
Where Libjavaplugin_oji.so is an older plug-in library, and Libnpjp2.so is a plug-in library that belongs to the Next-generation Java plugin-in technology. The first library has not been able to fully support the latest Java applet applications (see here, here and here, etc.). But Firefox 2 does not support the new Libnpjp2.so plug-in library, so only the first way to add the Libjavaplugin_oji.so plug-in library, and Firefox 3 fully support the latest plug-in library.
Finally, enter "About:plugins" in the Firefox address bar to see if the installation was successful.
Google-chrome for Linux
Execute the following command sequentially:
sudo mkdir/opt/google/chrome/plugins
Cd/opt/google/chrome/plugins
Ln-s/opt/java/jre1.6.0_19/lib/i386/libnpjp2.so
Google Chrome for Linux can only support next-generation Java plugin.
Also, enter about:plugins in the address bar to see if the installation was successful.