Here is a sample of JDiskExplorer JavaScript relying on Java 1.6 installation when JRE is not already installed.
codebase="http://java.sun.com/update/1.6.0/jinsta ... on=6,0,0,4"
...
type="application/x-java-applet;version=1.6"
...
<PARAM NAME="type" VALUE="application/x-java-applet;version=1.6">
...
Notice the three differences: