### Question:
StoreKeyConverterImplNoOp implements StoreKeyConverter { @Override public Map<StoreKey, StoreKey> convert(Collection<? extends StoreKey> input) throws Exception { Map<StoreKey, StoreKey> output = new HashMap<>(); if (input != null) { input.forEach((storeKey) -> output.put(storeKey, storeKey)); } return output; }  @Override Map<StoreKey, StoreKey> convert(Collection<? extends StoreKey> input); @Override StoreKey getConverted(StoreKey storeKey); @Override void dropCache();  }### Answer:
@Test public void testEmptyInput() throws Exception { Map<StoreKey, StoreKey> storeKeyMap = storeKeyConverter.convert(new ArrayList<>()); assertEquals("storeKeyMap should not have inputs", storeKeyMap.size(), 0); }
@Test public void testNullInput() throws Exception { Map<StoreKey, StoreKey> storeKeyMap = storeKeyConverter.convert(null); assertEquals("storeKeyMap should not have inputs", storeKeyMap.size(), 0); }