@Override
  public boolean hasNext() throws IOException {
    requirePeek();
    com.fasterxml.jackson.core.JsonToken token = peek;
    return token != END_OBJECT & token != END_ARRAY;
  }
{@link JsonReader} implementation backed by Jackson's {@link JsonParser}.
Provides measurable JSON parsing improvements over Gson's native implementation.
Error reporting might differ, however.
gson/src/org/immutables/gson/stream/JsonParserReader.java