@Override
    public List<CompletedCheckpoint> getAllCheckpoints() {
        return new ArrayList<>(completedCheckpoints);
    }
@Test
    void testRecoverSortedCheckpoints() throws Exception {
        final TestingStateHandleStore<CompletedCheckpoint> stateHandleStore =
                builder.setGetAllSupplier(() -> createStateHandles(3)).build();
        final CompletedCheckpointStore completedCheckpointStore =
                createCompletedCheckpointStore(stateHandleStore);
        final List<CompletedCheckpoint> recoveredCompletedCheckpoint =
                completedCheckpointStore.getAllCheckpoints();
        assertThat(recoveredCompletedCheckpoint).hasSize(3);
        final List<Long> checkpointIds =
                recoveredCompletedCheckpoint.stream()
                        .map(CompletedCheckpoint::getCheckpointID)
                        .collect(Collectors.toList());
        assertThat(checkpointIds).containsExactly(1L, 2L, 3L);
    }