Question

如何使WebClient下载外部css样式表和图像主体，就像通常的Web浏览器一样？

Answer 1

我现在正在做的是：

public static final HashMap<String, String> acceptTypes = new HashMap<String, String>(){{
        put("html", "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8");
        put("img", "image/png,image/*;q=0.8,*/*;q=0.5");
        put("script", "*/*");
        put("style", "text/css,*/*;q=0.1");
    }};

protected void downloadCssAndImages(HtmlPage page) {
        String xPathExpression = "//*[name() = 'img' or name() = 'link' and @type = 'text/css']";
        List<?> resultList = page.getByXPath(xPathExpression);

        Iterator<?> i = resultList.iterator();
        while (i.hasNext()) {
            try {
                HtmlElement el = (HtmlElement) i.next();

                String path = el.getAttribute("src").equals("")?el.getAttribute("href"):el.getAttribute("src");
                if (path == null || path.equals("")) continue;

                URL url = page.getFullyQualifiedUrl(path);

                WebRequestSettings wrs = new WebRequestSettings(url);
                wrs.setAdditionalHeader("Referer", page.getWebResponse().getRequestSettings().getUrl().toString());

                client.addRequestHeader("Accept", acceptTypes.get(el.getTagName().toLowerCase()));
                client.getPage(wrs);
            } catch (Exception e) {}
        }



client.removeRequestHeader("Accept");
}

Answer 2

来源：How to get base64 encoded contents for an ImageReader?

HtmlImage img = (HtmlImage) p.getByXPath("//img").get(3);
ImageReader imageReader = img.getImageReader();
BufferedImage bufferedImage = imageReader.read(0);
String formatName = imageReader.getFormatName();
ByteArrayOutputStream byteaOutput = new ByteArrayOutputStream();
Base64OutputStream base64Output = new base64OutputStream(byteaOutput);
ImageIO.write(bufferedImage, formatName, base64output);
String base64 = new String(byteaOutput.toByteArray());

Answer 3

以下是我提出的建议：

public InputStream httpGetLowLevel(URL url) throws IOException
{
    WebRequest wrq=new WebRequest(url);

    ProxyConfig config =webClient.getProxyConfig();

    //set request webproxy
    wrq.setProxyHost(config.getProxyHost());
    wrq.setProxyPort(config.getProxyPort());
    wrq.setCredentials(webClient.getCredentialsProvider().getCredentials(new AuthScope(config.getProxyHost(), config.getProxyPort())));
    for(Cookie c:webClient.getCookieManager().getCookies(url)){
        wrq.setAdditionalHeader("Cookie", c.toString());            
    }           
    WebResponse wr= webClient.getWebConnection().getResponse(wrq);
    return wr.getContentAsStream();
}

我的测试显示，它确实支持代理，并且它不仅携带来自WebClient的cookie，而且如果服务器在响应期间发送新的cookie，WebClient将会吃掉这些cookie

Answer 4

HtmlUnit不下载CSS或图像。它们对无头浏览器毫无用处......

最后我听说它在这里，但是票证标记为私人：http://osdir.com/ml/java.htmlunit.devel/2007-01/msg00021.html

如何告诉HtmlUnit WebClient下载图像和CSS？

4 个答案: