Hi!
Using Hibernate 2.1 with latest versions of XDoclet and HSQLDB.

I have a M:M relation between two tables; statistics_tbl (mapped as StatisticsBean) and test_tbl (TestBean). The TestBean adds statistics (using a java.util.Set with lazy invokation).

Like: new TestBean().addStatistics(new StatisticsBean());

Now, it seems like all instances belonging to a perticular testBean are beeing created each time new statistics are beeing added to the Set. Each testBean may have tens of thousands of statisticsbeans, which will affect performance if all instances have to be created for each add();.

Maybe the add() method calls size() which invokes the statisticsbeans???

How to solve this?

Thanks
/Martin

Here's my guess (perhaps not a good one). Since it is a Set, all elements must be unique. It has to therefore test this, and the only way to test uniqueness is to load the Set. Perhaps you want a Bag for this (allows duplicates, so in some cases will be faster at inserts, but slower at updates).

See http://www.hibernate.org/hib_docs/v3/reference/en/html/performance.html#performance-collections-mostefficentinverse