Java aplication not able to detect card reader sometimes

Question

Hi
We have a Java application (jre1.6.0_05.) which runs as window service under "Local System". It tries to detect card reader after every one minute. Normally it is working fine. However on some machines (which can be Windows XP, 2003 Server etc) some times it is not able to detect Card Reader, while other applications (which are not Java based) are able to detect. Sometimes service restart helps in solving the issue, but it reoccurs again after few hours/days.
Below is the exception we get:
javax.smartcardio.CardException: list() failed
at sun.security.smartcardio.PCSCTerminals.list(PCSCTerminals.java:109)
at javax.smartcardio.CardTerminals.list(CardTerminals.java:55)
Below is the code we are using to get list of terminals:
TerminalFactory factory = TerminalFactory.getDefault();
try {
terminals = factory.terminals().list();
} catch (CardException e) {
e.printStackTrace();
}Any idea what might be causing this random problem?

Answer 1

Hi,
According to the source for OpenJDK 6 (b19) the only way to get the exception you posted was with a PCSCException being thrown with the root exception wrapped in the new exception.
// from PCSCTerminals.list(State state)
try {
    // do some stuff to get the reader list
} catch (PCSCException e) {
    throw new CardException("list() failed", e);
}If this was not the case in the version you have, you will definitely see the root cause with the new JDK.
Cheers,
Shane