package com.dream.appserver.utils;
import org.springframework.stereotype.Service;
import org.springframework.web.multipart.MultipartFile;
import java.io.IOException;
import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.List;
import java.util.concurrent.Executors;
@Service
public class FileUpload {
    private final HttpClient httpClient = HttpClient.newBuilder().version(HttpClient.Version.HTTP_1_1).build();
    public void uploadFiles(List<MultipartFile> files, String uploadUrl) {
        try(var executor = Executors.newVirtualThreadPerTaskExecutor()) {
            files.forEach(file -> {
                executor.submit(() -> uploadFile(file, uploadUrl));
            });
        }
    }
    private void uploadFile(MultipartFile file, String uploadUrl){
        try {
            Path path = Files.createTempFile(file.getOriginalFilename(), null);
            Files.write(path, file.getBytes());
            HttpRequest request = HttpRequest.newBuilder()
                    .uri(URI.create(uploadUrl))
                    .header("Content-Type", "application/octet-stream")
                    .POST(HttpRequest.BodyPublishers.ofFile(path))
                    .build();
            HttpResponse<String> response = httpClient.send(request, HttpResponse.BodyHandlers.ofString());
            System.out.println(response.statusCode());
        } catch (IOException | InterruptedException e) {
            e.printStackTrace();
        }
    }
}

package com.dream.appserver.utils;
import org.springframework.stereotype.Service;
import java.io.InputStream;
import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.nio.file.StandardCopyOption;
import java.util.List;
import java.util.concurrent.Executors;
@Service
public class FileDownload {
    private final HttpClient httpClient = HttpClient.newBuilder().version(HttpClient.Version.HTTP_1_1).build();
    public void downloadFiles(List<String> downloadUrls, String filePath) {
        try(var executor = Executors.newVirtualThreadPerTaskExecutor()){
            for(String downloadUrl : downloadUrls){
                executor.submit(() -> {
                    downloadFiles(downloadUrls, filePath);
                });
            }
        }
    }
    private void downLoadFile(String downloadUrl, String filePath) {
        try {
            HttpRequest request = HttpRequest.newBuilder()
                    .uri(URI.create(downloadUrl))
                    .header("Content-Type", "application/octet-stream")
                    .GET()
                    .build();
            HttpResponse<InputStream> response = httpClient.send(request, HttpResponse.BodyHandlers.ofInputStream());
            if (response.statusCode() == 200) {
                Files.copy(response.body(), Paths.get(filePath), StandardCopyOption.REPLACE_EXISTING);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}