http://httpunit.sourceforge.net/

A JUnit extension for testing web applications.  Your test cases can emulate a browser and verify behavior of the application.  While it used to be that the emulation was low-level (at the HTTP protocol level, hence the name), higher level constructs are now available.

Also can be used with ServletUnit (included with HttpUnit) to test servlet-based apps without deploying to the container.

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Alternatives:
 * JwebUnit -- runs on top of HttpUnit for higher level constructs.  I no longer am using this, but some say it still provides benefits.
 * HtmlUnit

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BTW, I'm trying now to run HttpUnit with ServletUnit for testing a WebLogic 8.1 app.  I've installed some jar files from Tomcat 4.1.31 (I also tried Tomcat 3.3.2) to provide Jasper support.  I'm being stymied by an exception:

 com.meterware.httpunit.HttpInternalErrorException: Error on HTTP request: 500 javax.servlet.ServletException: org.apache.tools.ant.taskdefs.Javac.setTempdir(Ljava/io/File;)V [[http://localhost/index.jsp]]
	at com.meterware.servletunit.ServletUnitClient.newResponse(ServletUnitClient.java:115)
	at com.meterware.httpunit.WebWindow.getResource(WebWindow.java:164)
	at com.meterware.httpunit.WebWindow.getSubframeResponse(WebWindow.java:128)
	at com.meterware.httpunit.WebWindow.getResponse(WebWindow.java:121)
	at com.meterware.httpunit.WebClient.getResponse(WebClient.java:113)

Anyone know what that means?  Let me know.