@Override
  public void size(final int size) {
    if (size > a.length) {
      ensureCapacity(size);
    }
    if (size > this.size) {
      Arrays.fill(a, this.size, size, (null));
    } else {
      Arrays.fill(a, size, this.size, (null));
    }
    this.size = size;
  }
Grows this array list, ensuring that it can contain the given number of entries without
resizing, and in case enlarging it at least by a factor of two.

@param capacity the new minimum capacity for this array list.
geode-core/src/main/java/org/apache/geode/internal/cache/IdentityArrayList.java