Id assume someone with decent coding knowledge would atleast be able to use the search bar for a few seconds to see the hundreds of threads and tutorials that adress this. Read up, try things yourself or learn from the tuts, post when you have a prblem or issue with your project and people can help.
To start off, if.you want to directly alter the game you need to read write and edit as3, if you want something less direct, you could apply your java skills to modifying an already made proxy, or make your own.