I love doing online stock trading in my free time. Because I spend most of the day at my job I cannot do much of it. So, I'm thinking of making a software that will automatically place trades for me based on the trading strategy that I created. The trading platform that my broker provided me is java and html5 based and I access it with a web browser. My broker does not provide API for automated trading. I have understanding of some basic Javascript and Python programming. So, in order to make my algo trading software I need to do some reverse engineering. Don't know java (no time to learn also) and don't have enough money for hiring a programmer. Is there anyway I can reverse engineer a java applet using Python/Javascript? If I can, what else I need to learn about reverse engineering, as I know only basic python and JS.

  • 3
    I would be very careful with using an undocumented, reverse-engineered API for trading; changes to the API/network protocol won't be announced, and the result might prove quite costly. Commented Apr 29, 2015 at 13:40

2 Answers 2


If I understand well, you would like to reverse a Java applet in order to plug your own tool on a specific API (which is incidentally a trading platform).

I do not know why you are speaking about Javascript/Python... If you are reversing a Java application, then you need to know about Java applications... There is no escape from reality, unfortunately.

Anyway, what you need to use is a Java Decompiler in order to recover as much possible from the *.class files you got from the application you want to understand. There are several Java Decompilers that you can find, here is a small list (from the most featured to the least):

You can find more information by looking to this similar question on SO.


If its web based, you may not have to reverse the Java app.

Have you tried tools like Fiddler - http://www.telerik.com/fiddler - to capture web traffic that occurs when you execute a trade?

You could figure out what parts of the API the browser is actually calling when certain things are executed by capturing that in Fiddler.

You could then write a program in python to act as you in the browser.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.