下载整个网页 [英] Download the entire webpage
问题描述
可以使用 HTMLEditorKit
下载整个网页。但是,我需要下载需要滚动的整个网页才能加载其整个内容。这个技术最通常是通过与Ajax捆绑在一起的JavaScript来实现的。
There are ways to download an entire webpage, using HTMLEditorKit
. However, I need to download an entire webpage which needs scrolling in order to load its entire content. This technology is achieved most commonly through JavaScript bundled with Ajax.
Q。:有没有办法欺骗注定的网页,使用只有 Java代码
,以便下载其完整内容?
Q.: Is there a way to trick the destined webpage, using only Java code
, in order to download its full content?
Q.2:如果这不可能只有Java,那么是否可能与JavaScript结合?
Q.2: If this is not possible only with Java, then is it possible in combination with JavaScript?
简单的通知,我写的:
public class PageDownload {
public static void main(String[] args) throws Exception {
String webUrl = "...";
URL url = new URL(webUrl);
URLConnection connection = url.openConnection();
InputStream is = connection.getInputStream();
InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr);
HTMLEditorKit htmlKit = new HTMLEditorKit();
HTMLDocument htmlDoc = (HTMLDocument) htmlKit.createDefaultDocument();
HTMLEditorKit.Parser parser = new ParserDelegator();
HTMLEditorKit.ParserCallback callback = htmlDoc.getReader(0);
parser.parse(br, callback, true);
for (HTMLDocument.Iterator iterator = htmlDoc.getIterator(HTML.Tag.IMG);
iterator.isValid(); iterator.next()) {
AttributeSet attributes = iterator.getAttributes();
String imgSrc = (String) attributes.getAttribute(HTML.Attribute.SRC);
if (imgSrc != null && (imgSrc.endsWith(".jpg") || (imgSrc.endsWith(".jpeg"))
|| (imgSrc.endsWith(".png")) || (imgSrc.endsWith(".ico"))
|| (imgSrc.endsWith(".bmp")))) {
try {
downloadImage(webUrl, imgSrc);
} catch (IOException ex) {
System.out.println(ex.getMessage());
}
}
}
}
private static void downloadImage(String url, String imgSrc) throws IOException {
BufferedImage image = null;
try {
if (!(imgSrc.startsWith("http"))) {
url = url + imgSrc;
} else {
url = imgSrc;
}
imgSrc = imgSrc.substring(imgSrc.lastIndexOf("/") + 1);
String imageFormat = null;
imageFormat = imgSrc.substring(imgSrc.lastIndexOf(".") + 1);
String imgPath = null;
imgPath = "..." + imgSrc + "";
URL imageUrl = new URL(url);
image = ImageIO.read(imageUrl);
if (image != null) {
File file = new File(imgPath);
ImageIO.write(image, imageFormat, file);
}
} catch (Exception ex) {
ex.printStackTrace();
}
}
}
推荐答案
是的,您可以通过Java代码欺骗您的本地用户下载网页。您不能通过Java脚本下载HTMl静态内容。 JavaScript不提供您创建Java提供的文件。
Yes you can trick a a webpage to download on your locals by Java code. You can not Download HTMl Static content by Java Script. JavaScript is not providing you to create a files as Java Provides.
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
public class HttpDownloadUtility {
private static final int BUFFER_SIZE = 4096;
/**
* Downloads a file from a URL
* @param fileURL HTTP URL of the file to be downloaded
* @param saveDir path of the directory to save the file
* @throws IOException
*/
public static void downloadFile(String fileURL, String saveDir)
throws IOException {
URL url = new URL(fileURL);
HttpURLConnection httpConn = (HttpURLConnection) url.openConnection();
int responseCode = httpConn.getResponseCode();
// always check HTTP response code first
if (responseCode == HttpURLConnection.HTTP_OK) {
String fileName = "";
String disposition = httpConn.getHeaderField("Content-Disposition");
String contentType = httpConn.getContentType();
int contentLength = httpConn.getContentLength();
if (disposition != null) {
// extracts file name from header field
int index = disposition.indexOf("filename=");
if (index > 0) {
fileName = disposition.substring(index + 10,
disposition.length() - 1);
}
} else {
// extracts file name from URL
fileName = fileURL.substring(fileURL.lastIndexOf("/") + 1,
fileURL.length());
}
System.out.println("Content-Type = " + contentType);
System.out.println("Content-Disposition = " + disposition);
System.out.println("Content-Length = " + contentLength);
System.out.println("fileName = " + fileName);
// opens input stream from the HTTP connection
InputStream inputStream = httpConn.getInputStream();
String saveFilePath = saveDir + File.separator + fileName;
// opens an output stream to save into file
FileOutputStream outputStream = new FileOutputStream(saveFilePath);
int bytesRead = -1;
byte[] buffer = new byte[BUFFER_SIZE];
while ((bytesRead = inputStream.read(buffer)) != -1) {
outputStream.write(buffer, 0, bytesRead);
}
outputStream.close();
inputStream.close();
System.out.println("File downloaded");
} else {
System.out.println("No file to download. Server replied HTTP code: " + responseCode);
}
httpConn.disconnect();
}
}
这篇关于下载整个网页的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!