/**
     * <p> See this IBM article for information about InterruptedException and how I handled
     * it in this method.
     * <a href="http://www-128.ibm.com/developerworks/java/library/j-jtp05236.html#3.0">
     * Allowing a Thread to end
     * </a>
     * </p>
     *
     * @noinspection InfiniteLoopStatement
     * @see Thread#run()
     */
    public void run() {

        log.debug("Starting thread to purge expired objects from cache every "
                  + (purgeTimeMilliseconds / 1000) + " seconds");

        while (!Thread.currentThread().isInterrupted()) {

            log.trace("thread executing purgeExpired");

            cacheService.purgeExpired();

            try {

                sleep(purgeTimeMilliseconds);

            } catch (InterruptedException e) {

                /**
                 * @see http://www-128.ibm.com/developerworks/java/library/j-jtp05236.html#code5
                 * Allow this thread to end
                 */
            }
        }
    }