使用JAVA从HTML中提取所有图像

Question

I want to get the list of all Image urls from HTML source of a webpage(Both abosulte and relative urls). I used Jsoup to parse the HTML but its not giving all images. For example when I am parsing google.com HTML source its showing zero images..In google.com HTML source image links are in form..

"background:url(/intl/en_com/images/srpr/logo1w.png)

And in rediff.com the images links are in form..

videoArr[j]=new Array("http://ishare.rediff.com/video/entertainment/bappi-da-the-first-indian-in-grammy-jury/2684982","http://datastore.rediff.com/h86-w116/thumb/5E5669666658606D6A6B6272/v3np2zgbla4vdccf.D.0.bappi.jpg","Bappi Da - the first Indian In Grammy jury","http://mypage.rediff.com/profile/getprofile/LehrenTV/12669275","LehrenTV","(2:33)"); j = 1 videoArr[j]=new Array("http://ishare.rediff.com/video/entertainment/bebo-shahid-jab-they-met-again-/2681664","http://datastore.rediff.com/h86-w116/thumb/5E5669666658606D6A6B6272/ra8p9eeig8zy5qvd.D.0.They-Met-Again.jpg","Bebo-Shahid : Jab they met again!","http://mypage.rediff.com/profile/getprofile/LehrenTV/12669275","LehrenTV","(2:17)");

All images are not with in "img" tags..I also want to extract images which are not even with in "img" tags as shown in above HTML source.

How can I do this..?Please help me on this.. Thanks

Answer 1

This is going to be a bit difficult, I think. You basically need a library that will download a web page, construct the page's DOM and execute any javascript that may alter the DOM. After all that is done you have to extract all the possible images from the DOM. Another possible option is to intercept all calls by library to download resources, examine the URL and if the URL is an image record that URL.

My suggestion would be to start by playing with HtmlUnit(http://htmlunit.sourceforge.net/gettingStarted.html.) It does a good job of building the DOM. I'm not sure what types of hooks it has, for intercepting the methods that download resources. Of course if it doesn't provide you with the hooks you can always use AspectJ or simply modify the HtmlUnit source code. Good luck, this sounds like a reasonably interesting problem. You should post your solution, when you figure it out.

Answer 2

If you just want every image referred to in the page, can't you just scan the HTML and any linked javascript or CSS with a simple regex? How likely is it you'd get [-:_./%a-zA-Z0-9]*(.jpg|.png|.gif) in the HTML/JS/CSS that's not an image? I'd guess not very likely. And you should be allowing for broken links anyway.

Karthik's suggestion would be more correct, but I imagine it's more important to you to just get absolutely everything and filter out uninteresting images.