import org.apache.hadoop.yarn.server.nodemanager.recovery.NMStateStoreService.RecoveredDeletionServiceState; //导入依赖的package包/类
@Test
public void testDeletionTaskStorage() throws IOException {
  // test empty when no state
  RecoveredDeletionServiceState state =
      stateStore.loadDeletionServiceState();
  assertTrue(state.getTasks().isEmpty());

  // store a deletion task and verify recovered
  DeletionServiceDeleteTaskProto proto =
      DeletionServiceDeleteTaskProto.newBuilder()
      .setId(7)
      .setUser("someuser")
      .setSubdir("some/subdir")
      .addBasedirs("some/dir/path")
      .addBasedirs("some/other/dir/path")
      .setDeletionTime(123456L)
      .addSuccessorIds(8)
      .addSuccessorIds(9)
      .build();
  stateStore.storeDeletionTask(proto.getId(), proto);
  restartStateStore();
  state = stateStore.loadDeletionServiceState();
  assertEquals(1, state.getTasks().size());
  assertEquals(proto, state.getTasks().get(0));

  // store another deletion task
  DeletionServiceDeleteTaskProto proto2 =
      DeletionServiceDeleteTaskProto.newBuilder()
      .setId(8)
      .setUser("user2")
      .setSubdir("subdir2")
      .setDeletionTime(789L)
      .build();
  stateStore.storeDeletionTask(proto2.getId(), proto2);
  restartStateStore();
  state = stateStore.loadDeletionServiceState();
  assertEquals(2, state.getTasks().size());
  assertTrue(state.getTasks().contains(proto));
  assertTrue(state.getTasks().contains(proto2));

  // delete a task and verify gone after recovery
  stateStore.removeDeletionTask(proto2.getId());
  restartStateStore();
  state = stateStore.loadDeletionServiceState();
  assertEquals(1, state.getTasks().size());
  assertEquals(proto, state.getTasks().get(0));

  // delete the last task and verify none left
  stateStore.removeDeletionTask(proto.getId());
  restartStateStore();
  state = stateStore.loadDeletionServiceState();
  assertTrue(state.getTasks().isEmpty());
}