JsonNodeSerializer implements Serializer<String, JsonNode> { @Override public String deserializeKey(byte[] key) throws SerializationException { return new String(key, UTF_8); }  @Override String deserializeKey(byte[] key); @Override JsonNode deserializeValue(byte[] value); @Override byte[] serializeKey(String key); @Override byte[] serializeValue(JsonNode value);  }
@Test public void deserializeKey() { String result = underTest.deserializeKey(keyBytes); assertThat(result, is(key)); }