HtmlUnit is a "GUI-Less browser for Java programs". It models HTML documents and provides an API that allows you to invoke pages, fill out forms, click links, etc... just like you do in your "normal" browser.
It has fairly good JavaScript support (which is constantly improving) and is able to work even with quite complex AJAX libraries, simulating Chrome, Firefox or Internet Explorer depending on the configuration used.
It is typically used for testing purposes or to retrieve information from web sites.
HtmlUnit is not a generic unit testing framework. It is specifically a way to simulate a browser for testing purposes and is intended to be used within another testing framework such as JUnit or TestNG. Refer to the document "Getting Started with HtmlUnit" for an introduction.
HtmlUnit is used as the underlying "browser" by different Open Source tools like Canoo WebTest, JWebUnit, WebDriver, JSFUnit, WETATOR, Celerity, Spring MVC Test HtmlUnit, ...
HtmlUnit was originally written by Mike Bowler of Gargoyle Software and is released under the Apache 2 license. Since then, it has received many contributions from other developers, and would not be where it is today without their assistance.
Documentation
Tutorials
Place all the required jars in your classpath. All of these can be found in the lib directory of the HtmlUnit installation.
For maven, you would add:
<dependency>
<groupId>net.sourceforge.htmlunit</groupId>
<artifactId>htmlunit</artifactId>
<version>2.24</version>
</dependency>HtmlUnit provides excellent JavaScript support, simulating the behavior of the configured browser (Firefox or Internet Explorer). It uses the Rhino JavaScript engine for the core language (plus workarounds for some Rhino bugs) and provides the implementation for the objects specific to execution in a browser.
The unit tests of some well-known JavaScript libraries are included in HtmlUnit's own unit tests; based on these unit tests, the following libraries are known to work well with HtmlUnit:
Disabling JavaScript support: to disable JavaScript processing for one WebClient, call webClient.getOptions().setJavaScriptEnabled(false).
JavaScript code is executed just like in normal browsers when the page loads or when an handler is triggered. Additionally HtmlUnit provides the ability to inject code into an existing page via HtmlPage.executeJavascript(String yourJsCode).
Refer to the changes document for details on what is being added.