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How do i get the top losers or gainers on a particular day in java.(20 minute delay is not an issue). Is it possible to do this using yahoo finance. I am able to get information on a particular stock but none for the top losers on gainers of the day. I have checked out Stock Market API - Top Gainers/Losers but it doesnt seem to have a full answer.

Im working on a large Economy system for Bukkit and one of the things id like to do is Make a stock trading system. Where would i start and what is needed to have a perfect system?