code: public boolean hasExpired(Object key) {
  		if (key == null)
  			return false;
  
  		CacheLine line = (CacheLine) cacheLineTable.get(key);
  
  		return hasExpired(line);
  	}
docs: Returns a boolean specifying whether or not the element corresponding to
  the key has expired. Only returns true if element is in cache and has
  expired. Error conditions return false, if no expireTable entry, returns
  true. Always returns false if expireTime <= 0. Also, if SoftReference in
  the CacheLine object has been cleared by the gc return true.
  
  @param key
  The key for the element, used to reference it in the hastables
  and LRU linked list
  @return True is the element corresponding to the specified key has
  expired, otherwise false