db4o provides a special API to move classes between packages, rename classes or fields.
Use the configuration API to rename a class.You need to rename the class before you open the database.
configuration.common().objectClass("com.db4odoc.strategies.refactoring.PersonOld") .rename("com.db4odoc.strategies.refactoring.PersonNew");
Use the configuration API to rename a field. You need to rename the field before you open the database.
configuration.common().objectClass("com.db4odoc.strategies.refactoring.PersonOld") .objectField("name").rename("sirname");
The safe order of actions for renaming is: