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Lesson: All About Sockets (The Java™ Tutorials > Custom Networking)

Okay, I finally see what you're saying. Depending on what exactly the actions are, you could pull this off using the Robot class, but it's going to get complicated if you're doing any non-trvial...

Take a look at the Robot class.

...why do you need to do this? There might be a better way to accomplish your end goal.