Invoking REST API using spring resttemplate with JSON Response as POJO will degrade the performance?

问题

Greetings Spring Experts,

I am new to spring and trying to invoke an api using RestTemplate from my @Service class. I will be getting the response in the from of JSON.

I followed the json parsing with resttemplate to create my POJOs from the JSON response and used the following code to invoke the Rest API.

ResponseEntity<BackendAPI> response = restTemplate.exchange(URL,
            HttpMethod.GET, requestEntity, BackendAPI.class);

Then using the getter setters I am extracting the values from BackendAPI class and creating the JSON Object FrontendAPI.class to send the response to the caller of my sprint boot api.

Now there is another way of doing the same without manually creating the POJOs rather using ObjectMapper to dynamically create the JSON Object from the backend api response and traversing through the nodes to retrieve the values to create the FrontendAPI.class object as below.

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");

My JSON response from backend is similar to below

{
"@odata.context": "some context value here",
"value": [{
    "@odata.id": "odata id value1",
    "@odata.etag": "W/\"CQEet/1EgOuA\"",
    "Id": "id1",
    "Subject": "subject1"
}, {
    "@odata.id": "odata id value2",
    "@odata.etag": "W/\"CyEet/1EgOEk1t/\"",
    "Id": "id2",
    "Subject": "subject2"
}]

}

And I have 10 such endpoints to deal with.

So my real concern is by creating the POJOs from JSON and using resttemplate.exchange method to automap the response to POJO am I creating a performance hole?

In other words using ObjectMapper to dynamically map the response is better / faster way over using pre-defined POJOs?

Please Note, my backend api response object is static and the fields will not change.

Thanks in advance for your help.

来源：https://stackoverflow.com/questions/57767273/invoking-rest-api-using-spring-resttemplate-with-json-response-as-pojo-will-degr

标签

spring-boot

serialization

resttemplate