@Override
      public Object call() throws Exception {
        ClientCacheFactory cf = new ClientCacheFactory();
        cf.addPoolServer(getServerHostName(server1.getHost()), port);
        ClientCache cache = getClientCache(cf);
        cache.createClientRegionFactory(ClientRegionShortcut.CACHING_PROXY).create(regName);
        Region r1 = getRootRegion(regName);
        for (int i = 0; i < 20; i++) {
          r1.put("key-" + i, new PortfolioPdx(i));
        }
        return null;
      }
Used for saving & restoring oldObserver without serialization
geode-core/src/distributedTest/java/org/apache/geode/cache/query/dunit/SelectStarQueryDUnitTest.java