@Test
  public void testFacadeTotalBytesNoRegion() {
    CacheOperationFacade facade = new AutoBalancer().getCacheOperationFacade();

    assertThat(facade.getTotalDataSize(new HashMap<>())).isEqualTo(0);
  }
UnitTests for AutoBalancer. All collaborators should be mocked.
geode-rebalancer/src/test/java/org/apache/geode/cache/util/AutoBalancerJUnitTest.java