code: public synchronized E elementAt(int index) {
          if (index >= elementCount) {
              throw new ArrayIndexOutOfBoundsException(index + " >= " + elementCount);
          }
  
          return elementData(index);
      }
docs: Returns the component at the specified index.
  
  <p>This method is identical in functionality to the {@link #get(int)}
  method (which is part of the {@link List} interface).
  
  @param      index   an index into this vector
  @return     the component at the specified index
  @throws ArrayIndexOutOfBoundsException if the index is out of range
  ({@code index < 0 || index >= size()})