code: public boolean put(final int key) {
  		if (isFull()) { // full
  			resizeArray();
  		}
  		int slot = findSlotByKey(key);
  		if (slot >= 0) {
  			if (log.isDebugEnabled()) {
  				log.debug("key already exists: " + key);
  			}
  			return false; // key already exist
  		}
  		slot = ((-slot) - 1);
  		return addSlot(slot, key);
  	}
docs: put key
  
  @param key
  @return