JSoup 太棒了非常推荐。

I am working on crawler, which will search for goods in e-shops. It's my dissertation, so nothing commercial..

I use Java SE.

I will need some kind of advanced library, to make some tests for diagnostics (if that web page is what I am looking for), and for extracting relevant data from right ones.

Do you have personal experience with parser libraries to recommend me best one?

JSoup is fantastic. Highly recommended.