A small and simple java nfc writer/reader for the mifare ultralight C Tags written in Java 1.6
NFCReader reader = new NFCReader();
Properties tagContent=reader.read();
String tagID=tagContent.get(NFCReader.PROPERTY_TYPE_TAG_IDENTITY);
String tagValue=tagContent.get(NFCReader.PROPERTY_TYPE_TAG_VALUE);
... tagID contains the unique ID of the MIFARE-Ultralight C chip
... tagValue contains the userData of the MIFARE-Ultralight C chip
NFCWriter writer = new NFCWriter();
writer.write("Hello World");
NFCWriter writer = new NFCWriter();
writer.lockTag();
... (see the example in the folder appletDemo) or have a look in the wiki https://github.com/thomasX/nfc-util/wiki