Spring RestTemplate with paginated API

Question

Our REST APIs are returning results in Pages. Here is an example of one Controller

@RequestMapping(value = \"/search\", method = RequestMethod.GET, produces          


        

Answer 1

There is no need in implementing a Page. You just have to use a PagedResources<T> as a type in your ParameterizedTypeReference.

So if your service returns response similar to (objects are removed for brevity):

{
    "_embedded": {
        "events": [
            {...},
            {...},
            {...},
            {...},
            {...}
        ]
    },
    "_links": {
        "first": {...},
         "self": {...},
         "next": {...},
         "last": {...}
    },
    "page": {
        "size": 5,
        "totalElements": 30,
        "totalPages": 6,
        "number": 0
    }
}

And the objects you care are of type Event then you should execute the request like:

ResponseEntity<PagedResources<Event>> eventsResponse = restTemplate.exchange(uriBuilder.build(true).toUri(),
                HttpMethod.GET, null, new ParameterizedTypeReference<PagedResources<Event>>() {});

If you get hold of the resources like:

PagedResources<Event> eventsResources = eventsResponse.getBody();

you will be able to access the page metadata (what you get in the "page" section), the links ("_links" section) and the content:

Collection<Event> eventsCollection = eventsResources.getContent();