How to scrape a website with dynamic content loading? - java

How can I scrape a website with dynamic content loading, like a forbes.com article, but without using web-driver (it's slow) in apache http client.
I've tried getting the sitemap.xml but their sitemap includes only the latest articles and I want info from very old articles.
Also, I want a more generic solution and with the web-driver (I use selenium with phantomJS now) is site-specific and slow.

I'd suggest you to try this tool ui4j. It's a wrapper around the JavaFx WebKit Engine with headless modes. It can help you speeding up things.

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imitate browser with java

I'm looking for a java-framework which enables me to easily communicate with a website.
What I'd like to do is for example:
log into a website
open various pages
read information
submit information into forms
send ajax-requests
read ajax-response
What I'm not looking for is a browser automation plugin like selenium. I'm trying to have my application directly communicate with the website.
That's the general outline. If you can think of a better solution for the following problem, I'm more than willing to follow your advice (:
We're working with an webapplication with an gruesome GUI. Unfortunatley we've got no means to tinker with said application or request changes to it. What I'd ike to do is to build is a client which logs into said application, fetches the data and displays them in a more appropriate manner with additional information based on that data while also providing tools to process this data and submit it back to that web-application.
Thanks in advance.
Selenium does come for JAVA. You can download it from here. http://www.seleniumhq.org/download/
Here is a tutorial:
https://www.airpair.com/selenium/posts/selenium-tutorial-with-java
How Selenium web driver works
Selenium web driver (firefox web driver) will open a web browser(firefox) for you and you can actually see what's going on. The choice of opening a browser window may not be the requirement for you. Then you can use:
HTMLUnitWebDriver
PhantomJSDriverService
Take a look at
http://hc.apache.org/httpcomponents-client-ga/quickstart.html
Its not a framework but a library but should provide you the needed methods to interact with your web application

Parse a page (partly generated by JavaScript) by using Selenium

I've got a problem: I want to parse a page (e.g. this one) to collect information about the offered apps and save these information into a database.
Moreover I am using crawler4j for visiting every (available) page. But the problem - as I can see - is, that crawler4j needs links to follow in the source code.
But in this case the hrefs are generated by some JavaScript code so that crawler4j does not get new links to visit / pages to crawl.
So my idea was to use Selenium so that I can inspect several Elements like in a real Browser like Chrome or Firefox (I'm quite new with this).
But, to be honest, I don't know how to get the "generated" HTML instead of the source code.
Can anybody help me?
To inspect elements, you do not need the Selenium IDE, just use Firefox with the Firebug extension. Also, with the developer tools add on you can view a page's source and also the generated source (this is mainly for PHP).
Crawler4J can not handle javascript like this. It is better left for another more advanced crawling library. See this response here:
Web Crawling (Ajax/JavaScript enabled pages) using java

Replacement for Jaxer for parsing/crawling websites

I have an old tool an (ex-)colleague wrote a few years back with Jaxer, that I'd like to replace/rewrite.
Jaxer is an (abandoned) server-side framework based on a headless Mozilla/Gecko-Browser allowing you to use JavaScript and the DOM server-side.
Since Jaxer is abandoned and because I have big problems installing and running Aptana Studio 1.5 with Jaxer on a new computer, I'm looking for a library/framework/something on which I can base a new version.
This tool is only run locally inside Aptana Studio (the IDE for Jaxer) and was never intended to be an actual web app. It crawls our customers websites by loading them page by page into the server-side Mozilla. In order to do that it uses jQuery and predefined CSS selectors to find the links in the menus and parse other information out of the pages. The final result is basically a glorified sitemap.
I'd like to keep this modus operandi if possible and continue using jQuery/JavaScript/the DOM to load and parse/access the pages, but it can be wrapped in a framework based on another language such as Java. I considered writing something based on Gecko myself, but that seems a bit over the top, so I'm open for an other suggestions.
As far as HTML crawling/parsing goes:
http://ccil.org/~cowan/XML/tagsoup/
or
http://jsoup.org/

Use HtmlUnit as crawler

I needed a headless browser to parse pages.
HtmlUnit allow me to setup a Heroku Java app to fullfil this purpose.
But now I'm meeting with couple of issues.
The current one is malformed url "//path" instead of "/path" or "http(s)://path".
I downloaded sources of the 2.9.4 version and pushed tiny fixes in the sources ...
It's not really efficient to modify standard sources for obvious maintainability reasons.
I'm so wondering if i'm not digging in the wrong direction.
HtmlUnit is designed to browse pages in a testing purpose. Mine is to do like a browser, so make page working the most possible, especially because my damned targeted websites are the kind of ultra-dirty-not-respecting-anything...
What is your opinion about this retrospection ?
HTML Unit is used in Selenium 2/Web Driver for headless browser "simulation". There it works fine.
So I see no reason not to try Html Unit. May you can have a look at Selenium 2/Web Driver too.

autogenerate HTTP screen scraping Java code

I need to screen scrape some data from a website, because it isn't available via their web service. When I've needed to do this previously, I've written the Java code myself using Apache's HTTP client library to make the relevant HTTP calls to download the data. I figured out the relevant calls I needed to make by clicking through the relevant screens in a browser while using the Charles web proxy to log the corresponding HTTP calls.
As you can imagine this is a fairly tedious process, and I'm wodering if there's a tool that can actually generate the Java code that corresponds to a browser session. I expect the generated code wouldn't be as pretty as code written manually, but I could always tidy it up afterwards. Does anyone know if such a tool exists? Selenium is one possibility I'm aware of, though I'm not sure if it supports this exact use case.
Thanks,
Don
I would also add +1 for HtmlUnit since its functionality is very powerful: if you are needing behaviour 'as though a real browser was scraping and using the page' that's definitely the best option available. HtmlUnit executes (if you want it to) the Javascript in the page.
It currently has full featured support for all the main Javascript libraries and will execute JS code using them. Corresponding with that you can get handles to the Javascript objects in page programmatically within your test.
If however the scope of what you are trying to do is less, more along the lines of reading some of the HTML elements and where you dont much care about Javascript, then using NekoHTML should suffice. Its similar to JDom giving programmatic - rather than XPath - access to the tree. You would probably need to use Apache's HttpClient to retrieve pages.
The manageability.org blog has an entry which lists a whole bunch of web page scraping tools for Java. However, I do not seem to be able to reach it right now, but I did find a text only representation in Google's cache here.
You should take a look at HtmlUnit - it was designed for testing websites but works great for screen scraping and navigating through multiple pages. It takes care of cookies and other session-related stuff.
I would say I personally like to use HtmlUnit and Selenium as my 2 favorite tools for Screen Scraping.
A tool called The Grinder allows you to script a session to a site by going through its proxy. The output is Python (runnable in Jython).

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