Guys, I really need your help. I have a Project about any systems activities related to java Program and I choose Mini Search Engine. Can you please Help me of how to use Class and Objects cause I'm about to use them in my source code. thanks.

Just look on the web. You will find many tutorials on classes and objects. It's not realistic to expect someone here to write a new tutorial just for you.

DaniWeb Member Rules (which you agreed to when you signed up) include:
"Do provide evidence of having done some work yourself if posting questions from school or work assignments"
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Make a start, then when/if you get stuck post what you have done so far and someone will help you from there.