Can you return a response using OkHttp's enqueue method?

I currently use a normal newCall(Request).execute() as explained in one of Okio's examples, but I would prefer to use their enqueue method to have the action performed be async.

The issue I face however is the fact, that I have to return a String, which is generated from the response of the request.

In the case of the execute method does it look like this right now:

public class HttpUtil{
    private final OkHttpClient CLIENT = new OkHttpClient();

    public HttpUtil(){}
    
    public String getImage(String url) throws IOException{
        Request request = new Request.Builder()
                .url(url)
                .build();

        try(Response response = CLIENT.newCall(request).execute()){
            if(!response.isSuccessful())
                throw new IOException(String.format(
                        "Unexpected code from url %s: %s",
                        url,
                        response
                ));
            
            ResponseBody body = response.body();
            if(body == null)
                throw new NullPointerException("Received empty body!");
            
            String bodyString = body.string();
            if(bodyString.isEmpty())
                throw new NullPointerException("Received empty body!");
            
            return new JSONObject(bodyString).getString("link");
        }
    }
}

From the above method can you see that I generate a new JSONObject using the returned body as String and then get the field value of "link".

Is there now any way I could still return a String, while using the enqueue method?

Return a Future<String> so you are actually doing async programming, otherwise it's a pointless exercise to complicate the code using async methods while try to keep your simple sync method.

public class HttpUtil {
  private final OkHttpClient CLIENT = new OkHttpClient();

  public Future<String> getImage(String url) throws IOException {
    Request request = new Request.Builder()
      .url(url)
      .build();

    CompletableFuture<String> f = new CompletableFuture<>();

    CLIENT.newCall(request).enqueue(new Callback() {
        @Override
        public void onFailure(@NotNull Call call, @NotNull IOException e) {
          f.completeExceptionally(e);
        }

        @Override
        public void onResponse(@NotNull Call call, @NotNull Response response) throws IOException {
          if (!response.isSuccessful())
            throw new IOException(String.format(
              "Unexpected code from url %s: %s",
              url,
              response
            ));

          String bodyString = response.body().string();
          
          f.complete(new JSONObject(bodyString).getString("link"));
        }
      }
    );
    
    return f;
  }
}