Since we cant directly upload the Applet code into the google and then include it in the blogger post checkout the the way we have to add the Applet code into the blogger.
We cant simply add the Applet code to post in the blogger. For e.g. let us add the following applet code <applet code=ThreeD.class width=100 height=100></applet> into the post then we see a box with a 'x' mark on the left side corner as shown below.
Inorder to solve the problem we have to modify the Applet code so that blogger can track down where the following applet is actually present.
Solution to the problem comes up with a tag "codebase" ...
What is codebase?
Codebase tells the browser where the applet files are located, but if all files (including the HTML file, .class files, and images) are all together in one folder on your own server or local system, you should not specify CODEBASE. Likewise, if you are going to use the applet off-line, do not use a CODEBASE.
If you are using something like BLOGGER, then yes, you will definitely need to use a codebase address (since .class files can't be directly stored on the .blogspot server).
Something like this
<applet code=ThreeD.class width=100 height=100 codebase=http://www.yoursite.com/files/ ></applet>
I have provided the exact link location where the applet code is stored.