@Test
  public void testDoNotAddDefaultObserver() {
    conf.setBoolean(REMOVE_QUOTA_ON_TABLE_DELETE, false);
    master.updateConfigurationForQuotasObserver(conf);
    // Configuration#getStrings returns null when unset
    assertNull(conf.getStrings(MASTER_COPROCESSOR_CONF_KEY));
  }
Test class for MasterQuotasObserver that does not require a cluster.
hbase-server/src/test/java/org/apache/hadoop/hbase/quotas/TestMasterQuotasObserverWithMocks.java