@Nullable public static JsonParser enterPath(JsonParser parser, String path) throws IOException {
    if (!checkStartObject(parser, false)) return null;

    JsonToken value;
    while ((value = parser.nextValue()) != JsonToken.END_OBJECT) {
      if (value == null) {
        // End of input so ignore.
        return null;
      }
      if (parser.getCurrentName().equalsIgnoreCase(path) && value != JsonToken.VALUE_NULL) {
        return parser;
      } else {
        parser.skipChildren();
      }
    }
    return null;
  }
Navigates to a field of a JSON-serialized object. For example,

<pre>{@code
JsonParser status = enterPath(JsonAdapters.jsonParser(stream), "message", "status");
if (status != null) throw new IllegalStateException(status.nextString());
}</pre>
zipkin-storage/elasticsearch/src/main/java/zipkin2/elasticsearch/internal/JsonReaders.java