Address elements using json path in Jackson and Gson

Question

I want to address elements in a json object using their json path. Json-path java library provide such facility [1].

 String jsonString = "{\"delivery_codes\": [{\"postal_code\": {\"district\": \"Ghaziabad\", \"pin\": 201001, \"pre_paid\": \"Y\", \"cash\": \"Y\", \"pickup\": \"Y\", \"repl\": \"N\", \"cod\": \"Y\", \"is_oda\": \"N\", \"sort_code\": \"GB\", \"state_code\": \"UP\"}}]}";
 String jsonExp = "$.delivery_codes";
 JsonNode pincodes = JsonPath.read(jsonExp, jsonString, JsonNode.class);
 System.out.println("pincodesJson : "+pincodes);

Is it possible to do this using jackson or gson also instead of using json-path ?

Thanks

JsonPath is a JSON query library, Gson and Jackson are not and you have to traverse the latter JSON representations yourself. What's the real point of the question? — Lyubomyr Shaydariv, Apr 19 '17 at 10:58
I am going to do an performance evaluation and a comparison on similar libraries. Could you please provide me some Json query libraries? — Minudika, Apr 19 '17 at 11:03
Unfortunately no, I haven't heard any of such libraries other than JsonPath. — Lyubomyr Shaydariv, Apr 19 '17 at 11:05
Sachin Gupta has suggested a way to use Jackson `JsonNode.at`. I didn't know that Jackson provides this out of box. :) — Lyubomyr Shaydariv, Apr 19 '17 at 17:39

Sachin Gupta · Accepted Answer · 2017-04-19T11:07:34.793

You can try at method of Jackson JsonNode, which uses JSON pointer expression:

Eg:

String jsonString = "{\"delivery_codes\": [{\"postal_code\": {\"district\": \"Ghaziabad\", \"pin\": 201001, \"pre_paid\": \"Y\", \"cash\": \"Y\", \"pickup\": \"Y\", \"repl\": \"N\", \"cod\": \"Y\", \"is_oda\": \"N\", \"sort_code\": \"GB\", \"state_code\": \"UP\"}}]}";
ObjectMapper mapper = new ObjectMapper();
JsonNode node = mapper.readTree(jsonString);
int pincode = node.at("/delivery_codes/0/postal_code/pin").asInt();

Address elements using json path in Jackson and Gson

1 Answers1