Working for the enemy

I was offered a work in a company that works for banks, those damn thiefs. To add insult to the injury, they use Java as their main language.

What should i do? Do i sell my soul to the devil for the sweet bucks?

Take the job.

If you're in a position where money can make a difference in your life, put your morals on the backburner for a bit and make some money.  If you've got cash in the bank, take the job for the lulz.

Then, after you get a hold on the job and learn to coast, start using that free time you've earned to get some inside info.  Your local hacker group could benefit from this, and you could profit financially if you find the right set of people.  Shit, even an email list could be worthwhile if you're willing to phish. 

Just remember who the enemy is.