Robert Harper wrote:
>
> I am using the Tomcat user database to hold information for users. 
> What I need to do is retrieve the group a user is in from the 
> database. My problem comes when I have a servlet add a new user, 
> assign it to a roll and a group, then try to access the user from 
> another servlet running in the same context. I often get exceptions 
> thrown when I call the save() method on the user object stating that 
> Tomcat cannot rename the tomcat-users.xml to tomcat-users.xml.old. The 
> user info is still in memory and if enough time passes or the server 
> is stopped, the data eventually gets flushed to disk. There are 
> methods for finding the user, finding a roll, and finding a group, but 
> I don’t see a method for finding a group for a given user using the 
> MBeanServer().
>
> I had been using the XML libraries to load the database and then 
> search through it finding the user then getting the assigned roll but 
> it only works when the new user information is flushed to disk. What 
> would be the best way to do this?
>
Use some kind of a database related realm:

    * http://tomcat.apache.org/tomcat-5.5-doc/realm-howto.html#JDBCRealm
    * http://tomcat.apache.org/tomcat-5.5-doc/realm-howto.html#DataSourceRealm

Memory realm (tomcat-users.xml file) is a very simple one, following 
documentation: "*MemoryRealm* is a simple demonstration implementation 
of the Tomcat 5 |Realm| interface. It is not designed for production use."

-- 
Mikolaj Rydzewski      <miki@ceti.pl>        http://ceti.pl/~miki/
                    PGP KeyID: 8b12ab02
There are three kinds of people: men, women and unix.