用java语言写一个从http://www.nmc.cn/publish/radar/chinaall.html网页爬取雷达图片的程序

下面是一个使用Java语言和Jsoup库爬取http://www.nmc.cn/publish/radar/chinaall.html网页上雷达图片的程序：

import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;
import org.jsoup.select.Elements;
import java.io.BufferedInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.URL;

public class RadarImageCrawler {
    public static void main(String[] args) throws IOException {
        String url = "http://www.nmc.cn/publish/radar/chinaall.html";
        Document doc = Jsoup.connect(url).get();
        Elements imgElements = doc.select("#container > div > div > img");
        for (Element imgElement : imgElements) {
            String imgUrl = imgElement.absUrl("src");
            if (imgUrl.endsWith(".png")) {
                System.out.println("Downloading " + imgUrl);
                String fileName = imgUrl.substring(imgUrl.lastIndexOf("/") + 1);
                saveImage(imgUrl, fileName);
            }
        }
    }

    private static void saveImage(String imgUrl, String fileName) throws IOException {
        URL url = new URL(imgUrl);
        BufferedInputStream in = new BufferedInputStream(url.openStream());
        FileOutputStream out = new FileOutputStream(fileName);
        byte[] buf = new byte[1024];
        int n = 0;
        while ((n = in.read(buf)) != -1) {
            out.write(buf, 0, n);
        }
        in.close();
        out.close();
        System.out.println("Saved " + fileName);
    }
}

这个程序使用了Jsoup库来解析HTML文档，查找页面上所有的图片元素，并下载URL以“.png”结尾的图片。下载的图片将在程序的运行目录下保存。注意，下载图片可能需要一段时间，具体时间取决于网络速度和图片大小。