Configuration conf = new Configuration(false);
schedulerHandler.init(conf);
schedulerHandler.start();
String diagnostics = "Container preempted by RM.";
TaskAttemptImpl mockTask = mock(TaskAttemptImpl.class);
ContainerStatus mockStatus = mock(ContainerStatus.class);
ContainerId mockCId = mock(ContainerId.class);
AMContainer mockAMContainer = mock(AMContainer.class);
when(mockAMContainerMap.get(mockCId)).thenReturn(mockAMContainer);
when(mockAMContainer.getContainerId()).thenReturn(mockCId);