### Question:
ContainerDBServiceProviderImpl implements ContainerDBServiceProvider { @Override public void storeContainerKeyCount(Long containerID, Long count) throws IOException { containerKeyCountTable.put(containerID, count); } @Inject  ContainerDBServiceProviderImpl(DBStore dbStore,
                                        Configuration sqlConfiguration); @Override void close(); @Override void initNewContainerDB(Map<ContainerKeyPrefix, Integer>
                                     containerKeyPrefixCounts); @Override void storeContainerKeyMapping(ContainerKeyPrefix containerKeyPrefix,
                                       Integer count); @Override void storeContainerKeyCount(Long containerID, Long count); @Override long getKeyCountForContainer(Long containerID); @Override boolean doesContainerExists(Long containerID); @Override Integer getCountForContainerKeyPrefix(
      ContainerKeyPrefix containerKeyPrefix); @Override Map<ContainerKeyPrefix, Integer> getKeyPrefixesForContainer(
      long containerId); @Override Map<ContainerKeyPrefix, Integer> getKeyPrefixesForContainer(
      long containerId, String prevKeyPrefix); @Override Map<Long, ContainerMetadata> getContainers(int limit,
                                                    long prevContainer); @Override void deleteContainerMapping(ContainerKeyPrefix containerKeyPrefix); @Override long getCountForContainers(); @Override TableIterator getContainerTableIterator(); @Override void storeContainerCount(Long count); @Override void incrementContainerCountBy(long count);  }### Answer:
@Test public void testStoreContainerKeyCount() throws Exception { long containerId = 1L; long nextContainerId = 2L; containerDbServiceProvider.storeContainerKeyCount(containerId, 2L); containerDbServiceProvider.storeContainerKeyCount(nextContainerId, 3L); assertEquals(2, containerDbServiceProvider.getKeyCountForContainer(containerId)); assertEquals(3, containerDbServiceProvider.getKeyCountForContainer(nextContainerId)); containerDbServiceProvider.storeContainerKeyCount(containerId, 20L); assertEquals(20, containerDbServiceProvider.getKeyCountForContainer(containerId)); }