@Test
  public void testRegionClose() throws Exception {
    // start server first
    PORT1 = initServerCache(true);
    pool = (PoolImpl) createClientCache(NetworkUtils.getServerHostName(), PORT1);
    populateCache();
    registerInterestInBothTheRegions();
    closeBothRegions();

    assertFalse(pool.isDestroyed());
    pool.destroy();
    assertTrue(pool.isDestroyed());
    server1.invoke(ClientServerMiscDUnitTestBase::verifyNoCacheClientProxyOnServer);

  }
Test two regions: notify by subscription is true. Both the regions have registered interest in
all the keys. Close both the regions. When the last region is closed , it should close the
ConnectionProxy on the client , close all the server connection threads on the server & remove
the CacheClientProxy from the CacheClient notifier
geode-dunit/src/main/java/org/apache/geode/internal/cache/tier/sockets/ClientServerMiscDUnitTestBase.java