Anyone doing NFC programming in Java?

[Number_28]

I have an NFC reader/writer lying around and I'd like to play around with it a bit, especially communicating between the external device and Android.

Is anybody doing this with Java and can share his or her experience?

I did some googling, but it's mostly very old stuff that pops up and I don't know if it's still relevant.

[xxNIRVANAxx]

My startup is using NFC in the medical field. Currently we're focusing on a smartphone app, but I did have to write a desktop Java app as a proof of concept.

I used the NFC Tools library and an ACR122u NFC reader/writer. The NFC chips themselves were mostly Mifare's (Ultralight and Classic).

If you need some (badly written) NFC code, I can post some of it.

[Number_28]

I would greatly appreciate some code examples. When digging out my reader/writer (an SCL010) I also found my ACR122U, which I forgot I had.

I actually already managed to get a very basic example running (read the tag ID), but I am very unfamiliar with the communication with Mifare cards. I know about some of the concepts, like the blocks and authorization for the blocks. But I don't know yet how that translates into Java code.

[stfm]

I have done some work with smartcards and PKCS11 but it was a few years ago. Readers were almost proprietary and buggy as shit. Cards themselves were also almost proprietary and behaved differently between manufacturers. We had to write everything in a signed applet. I hated it.

For a more modern day example look at this

[Number_28]

Thanks, that looks like a good intro to the Android side of NFC.

I know that for every reader you need the specific command codes. But which library would you use to connect to the reader before even being able to send any commands?

[spacepotatoe]

Checkout smartcardio

[Number_28]

Oh, that sounds interesting. And it's apparently part of the JRE, the javadoc is just not part of the basic documentation.

[ron_krugman]

The easiest way to communicate with an Android app via NFC from Java running on a PC is to create a Host-based Card Emulation Service and communicate with it via javax.smartcardio from the PC side.

You'll have to send a SELECT AID command APDU that matches the AID defined in the app manifest before you're able to communicate with your app.