从URL获取图像(Java)

import java.net.*;
import java.io.*;

public class ImageDownloader {
    public static void main(String[] args) throws Exception {
        String url = "https://example.com/image.jpg";
        URLConnection connection = new URL(url).openConnection();
        connection.setRequestProperty("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.36");
        InputStream inputStream = connection.getInputStream();
        byte[] buffer = new byte[1024];
        int length = 0;
        while ((length = inputStream.read(buffer)) != -1) {
            System.out.write(buffer, 0, length);
        }
        inputStream.close();
    }
}