API or framework for handling transactions I am developing a JSP web (based on Java) and I would like to let users send the altcoins to my servers wallet. I need something what would monitor if the coins (DOGE/BTC etc.) has arrived and just after that let the users do something. 

Is there anything like this? I am new here and maybe it is broad but let me explain better if you need. 

I mean something like this: http://bitcoinj.github.io/getting-started

but not only for BTC also for other coins.
for example you can subscribe to unconfirmed transaction on the blockchain websocket and monitor when your addresses appear in the flow.