I am attempting to do what I would have guessed would be pretty simple, but as it turns out is not. I have an ACR122 NFC reader and a bunch of Mifare Classic and Mifare Ultralight tags, and all I want to do is read and write a mime-type and a short text string to each card from a Java application. Here's what I've got working so far:
- I can connect to my reader and listen for tags
- I can detect which type of tag is on the reader
- On the Mifare Classic tags I can loop through all of the data on the tag (after programming the tag from my phone) and build an ascii string, but most of the data is "junk" data
- I can determine whether or not there is an Application directory on the tag.
Here's my code for doing that:
Main:
public static void main(String[] args){
TerminalFactory factory = TerminalFactory.getDefault();
List<CardTerminal> terminals;
try{
TerminalHandler handler = new TerminalHandler();
terminals = factory.terminals().list();
CardTerminal cardTerminal = terminals.get(0);
AcsTerminal terminal = new AcsTerminal();
terminal.setCardTerminal(cardTerminal);
handler.addTerminal(terminal);
NfcAdapter adapter = new NfcAdapter(handler.getAvailableTerminal(), TerminalMode.INITIATOR);
adapter.registerTagListener(new CustomNDEFListener());
adapter.startListening();
System.in.read();
adapter.stopListening();
}
catch(IOException e){
}
catch(CardException e){
System.out.println("CardException: " + e.getMessage());
}
}
CustomNDEFListener:
public class CustomNDEFListener extends AbstractCardTool
{
@Override
public void doWithReaderWriter(MfClassicReaderWriter readerWriter)
throws IOException{
NdefMessageDecoder decoder = NdefContext.getNdefMessageDecoder();
MadKeyConfig config = MfConstants.NDEF_KEY_CONFIG;
if(readerWriter.hasApplicationDirectory()){
System.out.println("Application Directory Found!");
ApplicationDirectory directory = readerWriter.getApplicationDirectory();
}
else{
System.out.println("No Application Directory Found, creating one.");
readerWriter.createApplicationDirectory(config);
}
}
}
From here, I seem to be at a loss as for how to actually create and interact with an application. Once I can create the application and write Record objects to it, I should be able to write the data I need using the TextMimeRecord type, I just don't know how to get there. Any thoughts?
::Addendum:: Apparently there is no nfc-tools tag, and there probably should be. Would someone with enough rep be kind enough to create one and retag my question to include it?
::Second Addendum:: Also, I am willing to ditch NFC-Tools if someone can point me in the direction of a library that works for what I need, is well documented, and will run in a Windows environment.