= Class Diagram

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The diagram below shows a simplified version of Apache Causeway' internal metamodel.


[plantuml]
----
include::docs:resources:partial$plantuml-stereotypes.puml[]

package metamodel {

    class LogicalType<<value>> {
        +type
    }

    class Object\nSpecification<<desc>> {
        +objectSpecId
        ....
        -fullyQualifiedClassName
    }

    class Object\nMember<<desc>> {

    }

    class Object\nAction<<desc>> {

    }

    class Object\nAssociation<<desc>> {

    }

    class OneToOne\nAssociation<<desc>> {

    }

    class OneToMany\nAssociation<<desc>> {

    }

    interface FacetHolder<<desc>> {
    }

    class Object\nActionParameter<<desc>> {
    }

    class OneToOne\nActionParameter<<desc>> {
    }

    interface Facet<<desc>> {
    }

    class OneToMany\nActionParameter<<desc>> {
    }
}

package runtime {
    class ManagedObject<<ppt>> {
        +getSpecification()
        +getPojo()
    }
    class Bookmark<<value>> {

    }
}



Object\nSpecification -up-> LogicalType
Object\nSpecification -down-> "*" Object\nMember
Object\nMember ^-down- Object\nAssociation
Object\nMember ^-down- Object\nAction
Object\nAssociation ^-down- OneToOne\nAssociation
Object\nAssociation ^-down- OneToMany\nAssociation
Object\nActionParameter ^-down- OneToOne\nActionParameter
Object\nActionParameter ^-down- OneToMany\nActionParameter
Object\nAction -left-> "*" Object\nActionParameter

FacetHolder ^-.left- Object\nSpecification
FacetHolder ^-.down- Object\nMember
FacetHolder ^-.down- Object\nActionParameter
FacetHolder -right-> "*" Facet


ManagedObject  -up-> Bookmark

Bookmark -right-> LogicalType

----

where in the `metamodel` package:

`ObjectSpecification`:: is equivalent to `java.lang.Class`
`LogicalType`:: is a value object equivalent to the `@Named#value` attribute
`OneToOneAssociation`:: represents a scalar property
`OneToManyAssociation`:: represents a collection
`ObjectAction`:: represents an action (with multiple parameters, either scalar or list)

and in the `runtime` package:

`Bookmark`:: is equivalent to a tuple of `LogicalType` and an _Identifier_, appears in URLs in the Wicket and Restful Objects viewers

`ManagedObject`:: is equivalent to `java.lang.Object`
