写个多线程下载https资源的java代码

好的，以下是多线程下载https资源的Java代码：

import java.io.*;
import java.net.*;
import java.util.concurrent.*;

public class MultiThreadedDownloader {
    private static final int BUFFER_SIZE = 4096;
    private static final int MAX_THREADS = 10;

    public static void download(String urlStr, String savePath) throws IOException {
        URL url = new URL(urlStr);
        HttpURLConnection conn = (HttpURLConnection) url.openConnection();
        int responseCode = conn.getResponseCode();
        if (responseCode == HttpURLConnection.HTTP_OK) {
            int contentLength = conn.getContentLength();
            int numThreads = Math.min(MAX_THREADS, contentLength / BUFFER_SIZE);
            ExecutorService executor = Executors.newFixedThreadPool(numThreads);
            int startPos = ;
            int partSize = contentLength / numThreads;
            for (int i = ; i < numThreads; i++) {
                int endPos = startPos + partSize - 1;
                if (i == numThreads - 1) {
                    endPos = contentLength - 1;
                }
                executor.execute(new DownloadThread(url, startPos, endPos, savePath));
                startPos += partSize;
            }
            executor.shutdown();
            try {
                executor.awaitTermination(Long.MAX_VALUE, TimeUnit.NANOSECONDS);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        } else {
            throw new IOException("Server returned HTTP response code: " + responseCode);
        }
    }

    private static class DownloadThread implements Runnable {
        private URL url;
        private int startPos;
        private int endPos;
        private String savePath;

        public DownloadThread(URL url, int startPos, int endPos, String savePath) {
            this.url = url;
            this.startPos = startPos;
            this.endPos = endPos;
            this.savePath = savePath;
        }

        @Override
        public void run() {
            try {
                HttpURLConnection conn = (HttpURLConnection) url.openConnection();
                conn.setRequestMethod("GET");
                conn.setRequestProperty("Range", "bytes=" + startPos + "-" + endPos);
                InputStream inputStream = conn.getInputStream();
                RandomAccessFile file = new RandomAccessFile(savePath, "rw");
                file.seek(startPos);
                byte[] buffer = new byte[BUFFER_SIZE];
                int bytesRead;
                while ((bytesRead = inputStream.read(buffer)) != -1) {
                    file.write(buffer, , bytesRead);
                }
                file.close();
                inputStream.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

希望能对您有所帮助！