You have not described a scenario which requires an ESB. That is not to say that it might be useful in your architecture, but I'm just saying that the particular use case above does not require one. An ESB becomes very useful in cases where you need to do heterogeneous system integration, service orchestration and/or mediation.
If all you need is help with building up a persistence layer, then my gut reaction would be to suggest Hibernate Tools:
which can reverse-engineer an existing database schema and create the whole persistence layer for you.
When it comes to fronting it with JSF, you can go the standards-based approach and use JPA (which Hibernate implements), or take it a step farther and use something like JBoss Seam to easily wire together your presentation, business, and persistence tiers: