@Override
    public KTableValueGetterSupplier<K, KeyValue<K1, V1>> view() {
        final KTableValueGetterSupplier<K, V> parentValueGetterSupplier = parent.valueGetterSupplier();

        return new KTableValueGetterSupplier<K, KeyValue<K1, V1>>() {

            public KTableValueGetter<K, KeyValue<K1, V1>> get() {
                return new KTableMapValueGetter(parentValueGetterSupplier.get());
            }

            @Override
            public String[] storeNames() {
                throw new StreamsException("Underlying state store not accessible due to repartitioning.");
            }
        };
    }
KTable repartition map functions are not exposed to public APIs, but only used for keyed aggregations.
<p>
Given the input, it can output at most two records (one mapped from old value and one mapped from new value).
streams/src/main/java/org/apache/kafka/streams/kstream/internals/KTableRepartitionMap.java