Wanggang,
Could you please answer the following questions:
1) Are you connected to the Internet when you open the HQL editor or press refresh in the in-editor toolbar? If not, could you try connecting and see if it works then? (This is an issue we are trying to track down right now & I would like to ascertain immediately whether you are facing the same issue)
2) Could you please answer all the questions asked here: Posting Guidelines.
I am especially interested in your error log. Instructions are in the above link. Without your log it will be difficult to track down whatever issue you’re experiencing.
3) Do you have WTP or any other plugins installed? Have you changed your MyEclipse configuration in anyway?
4) Are you using the sample HibernateDemo project as is or have you added any libraries and made changes? Is your Hibernate configuration file valid?
5) Could you go here: Window>Preferences>MyEclipse>Editors>XML>XML Catalog and see if a
-//Hibernate/Hibernate Configuration DTD 3.0//EN entry is present? If you observe the Details Pane when you select this entry, you should get a file system URI – can you go to this location and check if the corresponding DTD file is OK? The file size should be 2547 bytes.
Best,
Brian.