private void removeFirst() {
    list.remove(1);
    assertEquals(6, list.size());
    for (int i = 0; i < 6; i++) {
      assertEquals(i + 2, list.get(i));
    }
  }
This tests concurrent modification of IndexElemArray and to make sure elementData and size are
updated atomically. Ticket# GEODE-106.
geode-core/src/test/java/org/apache/geode/cache/query/internal/index/IndexElemArrayJUnitTest.java