void validate(Region r1, Region r2) {
    if (!validate) {
      return;
    }

    Collection entrySet = r2.entrySet();
    Iterator iterator = entrySet.iterator();
    Map.Entry mapEntry = null;
    Object key, value = null;
    while (iterator.hasNext()) {
      mapEntry = (Map.Entry) iterator.next();
      key = mapEntry.getKey();
      value = mapEntry.getValue();
      if (!(r1.containsKey(key))) {
        fail(" region1 does not contain Key " + key + " but was expected to be there");
      }
      if (!(r1.get(key).equals(value))) {
        fail(" value for key " + key + " is " + r1.get(key)
            + " which is not consistent, it is supposed to be " + value);
      }
    }
    assertEquals(r2.size(), r1.size());

    r1.destroyRegion();
    r2.destroyRegion();
  }
Tests the bug where a get operation on an evicted entry fails to get value as the oplog is
deleted by the roller, but the entry was not rolled.
geode-core/src/integrationTest/java/org/apache/geode/internal/cache/ConcurrentRegionOperationsJUnitTest.java