gistfile1.java

/**
 * Artifício para evitar que o CLA do comando seja adulterado pela ChannelImpl.setChannel().
 * Thanks Bruno Jesus!
 * <p/>
 * Vide: http://www.java2s.com/Open-Source/Java/6.0-JDK-Modules-sun/security/sun/security/smartcardio/ChannelImpl.java.htm
 *
 * @param channel Canal
 * @param cla     CLA do comando
 */
private static void preventCLACorruption(CardChannel channel, int cla) {
    final int newChannelNumber = (((cla >= 0) && (cla <= 3)) ? cla : 0);
    if (channel.getChannelNumber() != newChannelNumber) {
        try {
            Field f = channel.getClass().getDeclaredField("channel");
            f.setAccessible(true);
            f.set(channel, newChannelNumber);
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
}