It is well-known fact that testing web pages is very hard by its characteristics.
One tool that professor suggested is HttpUnit:
http://httpunit.sourceforge.net/doc/cookbook.html
It is not so much surprising in the sense of technology. However, it had very interesting interface to test web pages. Most of web page testing tools mocks the behaviors of web browser. Some of them actually records tester's clicking.
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One of the approach of HttpUnit is parsing the HTML page into DOM tree, and returns some of parts that are interested to testers. The syntax gave me the impression that it seems like JavaScript syntax.
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However, we still have difficulty of web page testing. HttpUnit requires that the target web pages had to be deploied on web server, which takes fairly long time. I don't think we can skip the deploying part for testing. We need to test the very last result, which should be resulted by a web container. For this problem, we may need a light-weight web application server inside of IDEs.