JComboBox is a index-based component. This means that for every paint, it requests the model several getElementAt(x). When the model is small there is no problem, but when the model is bigger you start having a memory issue.
The first remedy is to store your ComboBoxModel on disk, but then you start seeing it's difficult to have a index-based database which is fast enough to this type of access.
On the other hand, Berkeley DB provides a really fast btree database, which solves the problem nicely. But, as a btree it looses a lot of performance to be able to do index-based lookups.
This project provides two new components: JIteratorList and JIteratorComboBox, their model is Iterator-based instead of index-based, which makes it perfect to use with bdb.
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