@Override
  public void removeElements(final int from, final int to) {
    it.unimi.dsi.fastutil.Arrays.ensureFromTo(size, from, to);
    System.arraycopy(a, to, a, from, size - to);
    size -= (to - from);
    int i = to - from;
    while (i-- != 0) {
      a[size + i] = null;
    }
  }
Removes elements of this type-specific list using optimized system calls.

@param from the start index (inclusive).
@param to the end index (exclusive).
geode-core/src/main/java/org/apache/geode/internal/cache/IdentityArrayList.java