private void stopManagerQuietly() {
    try {
      if (hasCache() && !basicGetCache().isClosed()) {
        stopManager();
      }
    } catch (DistributedSystemDisconnectedException | NullPointerException ignore) {
    }
  }
Note: Overriding MethodRule is only way to get {@code Object target}
geode-core/src/distributedTest/java/org/apache/geode/management/ManagementTestRule.java