@After
  public void tearDown() {
    for (VM vm : toArray(getController(), vm0, vm1, vm2, vm3, vm4)) {
      vm.invoke(() -> {
        stopLocator();
        disconnectFromDS();
        system = null;
        blackboard = null;
        hook = null;
      });
    }

    // delete locator state files so they don't accidentally get used by other tests
    Invoke.invokeInEveryVM(() -> {
      for (int port : new int[] {port1, port2, port3, port4}) {
        if (port > 0) {
          deleteLocatorStateFile(port);
        }
      }
    });
  }
Tests the ability of the {@link Locator} API to start and stop locators running in remote VMs.

@since GemFire 4.0
geode-core/src/distributedTest/java/org/apache/geode/distributed/LocatorDUnitTest.java