For the processdefinition there is a conversion script. Not sure if it covers everything but certainly saves you from a lot of manual work.
For the database there is (unfortunaltely) no tool for converting it. From jbpm3 on, we will make sure if there are any db changes that scripts will be available to do the conversion.
It also take a lot of work to change your code, since the core is completely different. We have a small abstraction framework between our application and jbpm and had it completely rewritten...
So it definitely need some manual work, but it pays well, because jBPM 3 is much nicer :-)
If you developed your own ui (as recommended) maybe, but the actionhandlers should still work.
When designpatterns are applied in the right places, even the ui should not be difficult to migrate. I myself tried as an off-the-record experiment to migrate a custom build ui for staffware to jBPM. Took me just three days.
we are also in the process of migration from 2.0 to 3.0. we are actually on Production and so there is a certain degree of risk involved in the migration effort. so we would like to know if there is any documentation at the schema level for both 2.0 and 3.0.
we do understand the 2.0 schema, but we have not much idea of the 3.0 schema, without going thrgh the source code. we will be able to achieve it, but since we are on production, its a bit risky proposition.
so if any of us have done the migration and there is some documentation or guidelines/checklist to do the migration, it would be helpful.
Thanks in advance,