RestTemplate and acessing json

Question

I have seen the responses from many other posts but would like to understand if there is a better way to do the same thing.

Requirement:- I am using restTemplate to talk to web service which returns JSON output which is dynamic. As a consumer I don't want to access all fields but is interested in few of them. I am using Spring framework with Jackson parser and found the way of accessing it

     String  response = restTemplate.getForObject(targetUrl, String.class);
     System.out.println(response);
     ObjectMapper mapper = new ObjectMapper();
     JsonNode rootNode = mapper.readValue(response, JsonNode.class);
     JsonNode uri = rootNode.get("uri");
     System.out.println(uri.asText());

Do you know any better way to do it? Mapping to java Object is something that I dont want to do as the json output is not in my control

Answer 1

If your RestTemplate is configured with the default HttpMessageConverters, which is provided by Jackson2ObjectMapperBuilder, you may directly get a JsonNode from restTemplate.getForObject.

For example,

ArrayNode resources = restTemplate.getForObject("/resources", ArrayNode.class);

Or,

ObjectNode resource = restTemplate.getForObject("/resources/123", ObjectNode.class);

Note that ArrayNode and ObjectNode are sub-classes of JsonNode.