import com.sun.security.sasl.util.AbstractSaslImpl; //导入依赖的package包/类
/**
 * This hack is done in order to fix a problem in Java 1.6 when using Kerberos
 * <p/>
 * Specific error:
 * java.lang.NullPointerException
 * at com.sun.security.sasl.util.AbstractSaslImpl.traceOutput(AbstractSaslImpl.java:241)
 * at com.sun.security.sasl.gsskerb.GssKrb5Client.evaluateChallenge(GssKrb5Client.java:180)
 */
private static void fixJavaKerberos() {
  try {
    Field loggerField = AbstractSaslImpl.class.getDeclaredField("logger");
    loggerField.setAccessible(true);

    java.util.logging.Logger logger = (java.util.logging.Logger) loggerField.get(null);
    if (logger == null) {
      logger = java.util.logging.Logger.getLogger("javax.security.sasl");
      setFinalStatic(loggerField, logger);
    }
    //Prevent the code in GssKrb5Client.evaluateChallenge to call traceOutput()
    logger.setLevel(Level.OFF);
  } catch (Exception e) {
    Logger.error("Error trying to fix Kerberos connection", e);
  }

}