Modeling a Relationship Between Entity Beans

Relationships can be modeled between any two entity beans on a class diagram. The entity bean at each end of a relationship must be EJB 2.0, with container-managed persistence and have a local interface.

To model a relationship between two Enterprise JavaBeans on a diagram:

1. Click the icon for the relationship you want to create, from those listed on the EJB Component Palette:
   
   
   • Relationship 1 to * 
   • Directed Relationship 1 to 1 
   • Directed Relationship 1 to * 
   • Directed Strong Aggregation 
     
     Notes: The navigability and multiplicity of a relationship end can be changed after it has been created.

If these icons are not displayed, select EJB from the dropdown on the Component Palette.

• Click the entity bean at the 'owning', or 'from', end of the relationship.

  Note: If you want to represent this relationship using a container-managed relationship (CMR) field, this is the bean in which the field will be created.

• Click the entity bean at the 'to' end of the relationship.
• Click the relationship line on the diagram, then click the text fields adjacent to the association to enter the relationship name.

  Note: To change the multiplicity of a relationship end on the diagram, right-click on the relationship end and choose either Multiplicity > 1 or Multiplicity > *.

Related topics

Modeling a Bean on a Diagram

Modeling a Reference Between Modeled Beans

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