private void evaluatePKIndexUsetest(RegionShortcut regionShortcut, String regionName)
      throws Exception {
    Cache cache = CacheUtils.getCache();
    Region r = cache.createRegionFactory(regionShortcut).create(regionName);
    Map map0 = new HashMap();
    Map map1 = new HashMap();
    Map map2 = new HashMap();
    r.put("A0", map0);
    r.put("A1", map1);
    r.put("A2", map2);
    qs.createIndex("pkIndex", IndexType.PRIMARY_KEY, "p.pk", SEPARATOR + regionName + " p");
    QueryObserverImpl observer = new QueryObserverImpl();
    QueryObserverHolder.setInstance(observer);
    SelectResults sr = (SelectResults) qs
        .newQuery("select * from " + SEPARATOR + regionName + " p where p.pk = 'A1'").execute();
    assertEquals(1, sr.size());

    if (!observer.isIndexesUsed) {
      fail("Index not used for operator '='");
    }
  }
Test to check if Region short cut method is used for querying, the Primary key index
utilization occurs or not
geode-core/src/integrationTest/java/org/apache/geode/cache/query/internal/index/IndexUseJUnitTest.java