public static void tryLoggingClassPaths(JobConf job, Logger logger) {
    if (logger != null && logger.isDebugEnabled()) {
      tryToLogClassPath("conf", job.getClassLoader(), logger);
      tryToLogClassPath("thread", Thread.currentThread().getContextClassLoader(), logger);
    }
  }
Logs the class paths of the job class loader and the thread context class loader to the passed logger.
Checks both loaders if getURLs method is available; if not, prints a message about this (instead of the class path)

Note: all messages will always be logged with DEBUG log level.
ql/src/java/org/apache/hadoop/hive/ql/exec/Utilities.java