Friday Demo

FridayDemo.java

package com.bobocode.lesson12;

import com.bobocode.lesson11.NasaResponse;
import com.bobocode.lesson11.Photo;
import org.apache.commons.lang3.tuple.Pair;
import org.springframework.web.client.RestTemplate;

import java.net.URI;
import java.util.*;
import java.util.concurrent.CompletableFuture;
import java.util.stream.Collectors;

public class FridayDemo {
    /*HOMEWORK  #11
        Additional part:
        Speed up your implementation using multiple threads
        Make sure that it works faster than a single-thread impl
        Post a screenshot of your solution
        Implement the same logic using another HTTP client library
        Make sure that it gives the same result
        Post a screenshot of your solution*/

    public static final String NASA_URL = "https://api.nasa.gov/mars-photos/api/v1/rovers/curiosity/photos?sol=15&api_key=DEMO_KEY";

    public static void main(String[] args) {
        RestTemplate restTemplate = new RestTemplate();
        long start = System.currentTimeMillis();
        var response = restTemplate.getForObject(NASA_URL, NasaResponse.class);

        CompletableFuture<Pair<String, Long>>[] array = restTemplate
                .getForObject(NASA_URL, NasaResponse.class)
                .getPhotos().stream()
//                .parallel()
                .map(Photo::getImgSrc)
                .map(img -> {
                    return CompletableFuture.supplyAsync(() -> restTemplate.headForHeaders(URI.create(img)).getLocation())
                            .thenApply(uri -> Pair.of(img, restTemplate.headForHeaders(uri).getContentLength()));
                })

                .toArray(CompletableFuture[]::new);


        CompletableFuture<Void> allOf = CompletableFuture.allOf(array);
        List<Pair<String, Long>> longs = new ArrayList<>();
        for (CompletableFuture<Pair<String, Long>> completableFuture : array) {
            longs.add(completableFuture.join());
        }

        longs.stream().max(Comparator.comparing(Pair::getRight)).ifPresent(System.out::println);
        long time = System.currentTimeMillis() - start;
        System.out.printf("%s millis\n", time);


//        Map<String, Long> map = Objects.requireNonNull(response).getPhotos()
//                .stream()
//                .map(Photo::getImgSrc)
//
//                .collect(toMap(s -> s, img -> {
//
////                    return CompletableFuture.supplyAsync(() -> restTemplate.headForHeaders(img).getLocation())
////                            .thenApply(uri -> restTemplate.headForHeaders(uri).getContentLength())
////                            .join();
//                    URI uri = restTemplate.headForHeaders(img).getLocation();
//                    return restTemplate.headForHeaders(uri).getContentLength();
//                }));


//        long time = System.currentTimeMillis() - start;
//        Optional<Map.Entry<String, Long>> max = map.entrySet()
//                .stream()
//                .max(Map.Entry.comparingByValue());
//
//        max.ifPresent(x -> {
//            System.out.println("img_src:" + x.getKey());
//            System.out.println("size:" + x.getValue());
//        });
    }
}