### Question:
CGroupsMemoryResourceHandlerImpl implements MemoryResourceHandler { @Override public List<PrivilegedOperation> teardown() throws ResourceHandlerException { return null; } CGroupsMemoryResourceHandlerImpl(CGroupsHandler cGroupsHandler); @Override List<PrivilegedOperation> bootstrap(Configuration conf); @Override List<PrivilegedOperation> reacquireContainer(ContainerId containerId); @Override List<PrivilegedOperation> updateContainer(Container container); @Override List<PrivilegedOperation> preStart(Container container); @Override List<PrivilegedOperation> postComplete(ContainerId containerId); @Override List<PrivilegedOperation> teardown(); @Override String toString();  }### Answer:
@Test public void testTeardown() throws Exception { Assert.assertNull(cGroupsMemoryResourceHandler.teardown()); }