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@Evolving
public class KeyQuery<K, V> implements Query<V> {
  // static factory to create a new KeyQuery, given a key
  public static <K, V> KeyQuery<K, V> withKey(final K key);

  // getter for the key
  public K getKey();
}

// ======================================
// example usage in IQIQv2:

Integer key = 1;

// note that "mystore" is a KeyValueStore<Integer, ValueAndTimestamp<Integer>>,
// hence the result type        
InteractiveQueryRequest<ValueAndTimestamp<Integer>> query =
  inStore("mystore")
    .withQuery(KeyQuery.withKey(key));
     
// run the query
InteractiveQueryResult<ValueAndTimestamp<Integer>> result = kafkaStreams.query(query);

// In this example, it doesn't matter which partition ran the query, so we just
// grab the result from the partition that returned something
// (this is what IQ currently does under the covers).

Integer value = result.getOnlyPartitionResult().getResult().value();

// ======================================
// For comparison, here is how the query would look in current IQ:
// (note, this glosses over many of the problems described above.
//  the example is here to illustrate the different ergonomics
//  of the two APIs.)

// create the query parameters
StoreQueryParameters<ReadOnlyKeyValueStore<Integer, ValueAndTimestamp<Integer>>> storeQueryParameters =
  StoreQueryParameters.fromNameAndType(
    "mystore", 
    QueryableStoreTypes.timestampedKeyValueStore()
  );

// get a store handle to run the query
ReadOnlyKeyValueStore<Integer, ValueAndTimestamp<Integer>> store =
  kafkaStreams.store(storeQueryParameters);

// query the store
Integer value1 = store.get(key).value();