@Test
    public void getCacheSingleton_returnsNullInAllVMs() {
      assertThat(GemFireCacheImpl.getInstance()).isNull();
      for (VM vm : getAllVMs()) {
        vm.invoke(() -> assertThat(GemFireCacheImpl.getInstance()).isNull());
      }
    }
Used by test {@link #defaultDoesNothing()}.

<p>
NOTE: please keep the use of deprecated GemFireCacheImpl.getInstance().
geode-dunit/src/distributedTest/java/org/apache/geode/test/dunit/rules/tests/CacheRuleBuilderDistributedTest.java