@Override
      public void run() {
        Region region = getRootRegion(regionName);
        assertEquals("a", region.get("a"));
        assertEquals("b", region.get("b"));
        assertEquals(null, region.get("c"));
        assertEquals(null, region.get("d"));
      }
Test the we can have both a connection pool and a cache writer.

The expected order of operations for put is: local writer put on server
geode-core/src/distributedTest/java/org/apache/geode/cache/ConnectionPoolAndLoaderDUnitTest.java