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

Solution

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.