客户端响应过滤器读取实体问题（泽西）

Question

Im using Jerseys client side filters for caching. Request for reading and response for caching values. How to read entity body from client response filter, dont have methods like read, getEntity when using normal client calls from client builder. Only method i found maybe usefull is getEntityStream but not having much luck with it. For caching im using EhCache. Im novice user help:)

REQUEST:

public class ClientCacheResponseFilter implements ClientResponseFilter

private Ehcache ehcache;

public ClientCacheRequestFilter(Ehcache ehcache) {
    this.ehcache = ehcache;
}

@Override
public void filter(ClientRequestContext request) throws IOException {
    System.out.println("REQUEST FILTER");

    if (!request.getMethod().equalsIgnoreCase("GET")) {
        return;
    }
    String key = request.getUri().toString();
    System.out.println("REQ KEY: " + key);

    System.out.println("LOOKING FOR CACHE");
    if (!ehcache.getClientCache().containsKey(key)) {
        System.out.println("EMPTY CACHE");
        return;
    }

    Cache<String, Object> cache = ehcache.getClientCache();
    Object value = cache.get(key);
    if (value != null) {

        System.out.println("REQUEST FILTER - SECOND TIME READING CACHE");
        System.out.println("CACHE ENTRY VALUE: " + value);

        Response response = Response.ok()
                .entity(value)
                .type(MediaType.APPLICATION_JSON)
                .build();

        System.out.println("SENDING ENTITY");
        request.abortWith(response);
    }
}

RESPONSE:

private Ehcache ehcache;

public ClientCacheResponseFilter(Ehcache ehcache) {
    this.ehcache = ehcache;
}

@Override
public void filter(ClientRequestContext request, ClientResponseContext response) throws IOException {
    System.out.println("RESPONSE FILTER");
    if (!request.getMethod().equalsIgnoreCase("GET")) {
        return;
    }

    if (response.getStatus() == 200) {

        System.out.println("CACHING VALUE");
        String key = request.getUri().toString();

        ehcache.getClientCache().put(key,  ?);  // GET ENTITY FROM RESPONSE ?
        
    }
}

CLIENT CALL:

    WebTarget webTarget = CLIENT.target(API_URL).path("games");
    Invocation.Builder builder = webTarget.request(MediaType.APPLICATION_JSON);
    
    try (Response response = builder.get()) {
        
        if (response.getStatus() == 200) {
            return response.readEntity(new GenericType<List<Game>>() {
            });
        }
    }
    return Collections.EMPTY_LIST;
}

Answer 1

Assuming you are using Jersey 2.x, the ClientResponseContext can be cast to the Jersey specific ClientResponse , which has the readEntity(..) method (similar to the client Response#readEntity() method). You also can call bufferEntity() before you read the entity. This way the client will be able to read the entity again.

So for example if you want to get the JSON string response, you can simply do

// in response filter
ClientResponse res = (ClientResponse) response;
res.bufferEntity();
String jsonResponse = res.readEntity(String.class);