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${__javaScript(rndStocks =Math.floor(Math.random()*('${numberStocks}'));$numberStocks='${numberStocks}' - rndStocks; ,numberOfSellStocks)}
Get a random number between 0 and jmeter varialbe numberStocks then subtract that number from numberStocks returns rndStocks in numberOfSellStocks
Embeded Browser Stuff.
JDIC ( Java desktop ) BlackBerry (Mozilla) Both above require Mozilla installed and are not very fun
Flyingsuacer A pure java XHTML renderer. Looks Promising.