Apr 25
Handy Hibernate 3 Logger Reference
In my [admittedly] limited 3 years of using Hibernate, I’ve found that a lot of folks are confused about what loggers to use when trying to debug Hibernate issues.
These people (myself included, on occasion) will end up opening the floodgates and doing something like this (log4j) syntax:
<logger name="org.hibernate">
<level value="DEBUG">
</level>
</logger>
While this (obviously) works, Hibernate is nothing if not verbose in its logging, and this will easily generate megabytes of Hibernate logs.
Hibernate uses the standard logging pattern of naming loggers after the classes they’re enclosed in, as suggested by Sun itself. So if you’re familiar with the Hibernate code, it can be fairly easy to pick out the right package qualifier in your logging configuration to get logging where you want it.
Unfortunately, many/most developers aren’t familiar enough with the Hibernate source code to know these things off the top of their heads.
Thankfully, the Hibernate folks have kindly documented some logging settings, including logging of SQL (which is the simple shortcut org.hibernate.SQL.
I have a couple more useful loggers to add to the list:
- org.hibernate.engine.query.HQLQueryPlan – which will display the source of any HQL query executed prior to execution and parameter binding
- org.hibernate.engine.QueryParameters – will display the name / value pairs of query parameters bound to HQL queries
I’ll plan on updating this post with additional information as I run across it.
