无法获取HTTP响应的JSON

Question

I'm simply trying to get the JSON returned by a HTTP GET request in Java 8. My code:

import javax.ws.rs.client.Client;
import javax.ws.rs.client.ClientBuilder;

Client client = ClientBuilder.newClient();

Response response = client.target("https://dog.ceo/api/breeds/list/all")
        .request()
        .header("Content-type", MediaType.APPLICATION_JSON)
        .get();

String json_string = EntityUtils.toString(response.getEntity());

I get error with the last line:

java: incompatible types: java.lang.Object cannot be converted to org.apache.http.HttpEntity

How can I simply get JSON from the response?

I have tried:

    JSONObject jsonObject = client.target("https://dog.ceo/api/breeds/list/all")
            .request()
            .header("Content-type", MediaType.APPLICATION_JSON)
            .get(JSONObject.class);

    System.out.println("jsonObject is " + jsonObject);

I get the error:

javax.ws.rs.client.ResponseProcessingException: org.glassfish.jersey.message.internal.MessageBodyProviderNotFoundException: MessageBodyReader not found for media type=application/json, type=class org.json.JSONObject, genericType=class org.json.JSONObject.

I also tried:

    Response response = client.target("https://dog.ceo/api/breeds/list/all")
            .request()
            .header("Content-type", MediaType.APPLICATION_JSON)
            .get();

    System.out.println(response.getEntity().toString());

I get: org.glassfish.jersey.client.internal.HttpUrlConnector$2@350d3f4d

How can something this basic - get me JSON from Response - be so difficult?

Answer 1

The Problem is this part:

// [...]
String json_string = EntityUtils.toString(response.getEntity());

---

Try doing it like this:

// [...]
String json_string = EntityUtils.toString((HttpEntity) response.getEntity());

It's just a guess though, since I don't have a running code i can not test it.

Answer 2

May try to use response.readEntity(String.class) or response.readEntity(HttpEntity.class) . https://docs.oracle.com/javaee/7/api/javax/ws/rs/core/Response.html#readEntity-java.lang.Class- That should give you a type you can work with.

EDIT: response.readEntity(String.class) did work in the end.