Both having pros and cons which will be explained in (earlier) posts below and summarized in the last section. For this list I have tried two different implementations a ice:selectManyListbox and an ice:dataTable toegether with ice:rowSelector.
ICEFACES ROWSELECTOR HOW TO
I'll leave vanilla attributes out of scope, and only look on how to select the roles the user wishes the subject to fulfill (role creation is left out of this use case). I have chosen for a master detail view: A list of all subjects, clicking on one subject presents you the subject in focus and the possibility to edit the subject's attributes. We're approaching our final goal: how to display this in a gui. The 2 one-2-many relationships are intuitively mapped in the entities Subject, Actor and Role. I'm not completely sure this is the right approach but for me it worked well. So instead of modeling a many2many relationship I modeled 2 one-to-many relationships. However in the end it turns out to be dead meat (see question 6 and 7). You loose control over your join table (in my use case, an actor exists for a certain period, for a new period the actor must be cloned), see also this blog, where the author introduces some life in the join table. However I'm not convinced this is the way to go to map many-to-many relations. In ejb3 the possibility exists to directly indicate a many-to-many relation ship using an annotation with the same name and indicating a join-table. The actor is a period based entity, during a season, the next season he may give up his role as trainer, or give up his role as competition member. Of course a role maybe played by many actors, and a subject may fulfill many roles. A subject performing a role becomes an actor. I have a subject (which may be of interest to our club: a person, store selling us volleybals, the room landlord etc) Furter I have roles, some of the roles will be connected to posts on the balance sheets (like credit, trainer, rent or debitor: compition player, recreational player). The versions used in this example: jboss 4.2 (ejb3), seam 1.2.1, mysql 5.0m icefaces 1.6.0 and jsf-ri (?.?) Please note that this example is part of my "project" accountancy for sportclubs, see earliest blog for more details. Note that here is quite some documentation on the ejb (jpa) modelling, but the actual gui implementation is missing in most cases. I havent found too much documentation or examples on the internet, so I thought I just publish my own efforts here. Introduction many to many A challenging and interesting usecase for me has been the implementation of a many-to-many relations in a user interface.
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