JavaCard OS

I came across an problem when using the Java Smart Card I/O API. No matter when I send a command APDU to my applet, and this command returns any data, and an exception is thrown:

Exception in thread "main" javax.smartcardio.CardException: Could not obtain response
at sun.security.smartcardio.ChannelImpl.doTransmit(ChannelImpl.java:169)
at sun.security.smartcardio.ChannelImpl.transmit(ChannelImpl.java:73)

Does anybody know how do I solve this problem?

I think that you are sending an APDU command case 1 (P3=0), just like:


If your applet invoke the method

, it will expect data from the APDU buffer, and if you don't send data, this exception will be throwed by smartcardio API.

So as what has been mentioned above, even for APDU commands that are sent without any data attached. You have to send a dummy data attached to it.

At the applet side, do a setIncomingAndReceive()
first and ignore the retrieved dummy data. then proceed with your response.