code: private final void resizeArray() {
  		if (log.isDebugEnabled()) {
  			log.debug("resizeArray size=" + keys.length + " newsize=" + (keys.length << 1));
  		}
  		final int[] newkeys = new int[keys.length << 1]; // double space
  		System.arraycopy(keys, 0, newkeys, 0, allocated);
  		keys = newkeys;
  	}
docs: Resize array