I have to create a query in our backend application using the parameters obtained from the client. Consider this diagram:

I have entities (Type field), those entities’ fields (Parameter), a relation, a value and an operand. So in sql terms the table above translates to this:
... WHERE Item.reach_complience = ”<1%”
and Item.technical.type = ”RES”
and Item.technical.value <= ”1k”
and Item.technical.value >= ”4K7”
and (Item.technical.footprint = ”RC0603” or Item.technical.footprint = ”RC0805”)
and Item.classification.incurrent_handling = ”prefered-to-use”
I really don’t want to reinvent the weel here, so my question is:
Is there a Criteria factory libarary which uses JPA or more specifically Hibernate or is there some 3rd party library which can be used to create criteria queries? We are using Eclipse RCP on the frontend and data arrives to the backend (Spring) through an Apache Cxf service. I wish to write maintainable using JPA’s query syntax.
Yes. I think
ISearchis the best: http://code.google.com/p/hibernate-generic-dao/wiki/Search