i3.dragos.gm.core.proxy
Class RelationClassProxy

java.lang.Object
  i3.dragos.gm.core.proxy.GraphEntityClassProxy
      i3.dragos.gm.core.proxy.RelationClassProxy

All Implemented Interfaces:

ExistenceCheckable, GraphEntityClass, MetaAttributable, RelationClass

public class RelationClassProxy
extends GraphEntityClassProxy
implements RelationClass

An RelationClassProxy delegates all method calls to the underlying relation class except for those that access fields which are used after an relation class has been deleted.

Author:

Boris Boehlen <boehlen@cs.rwth-aachen.de>

Field Summary

Fields inherited from class i3.dragos.gm.core.proxy.GraphEntityClassProxy

proxiedEntityClass

Constructor Summary

RelationClassProxy(RelationClass e)
Constructs a new wrapper for an relation class.

Method Summary

RelationEndClass	declareRelationEndClass(java.lang.String name, GraphEntityClass target, Cardinality card, RelationEndDirection direction) Adds a relation end to the relation class.
java.util.Collection<? extends RelationEndClass>	getRelationEndClasses() Returns a collection with all relation ends of the relation class.
void	undeclareRelationEndClass(RelationEndClass rec) Undeclares a relation end previously declared for the relation class.

Methods inherited from class i3.dragos.gm.core.proxy.GraphEntityClassProxy

addSubClass, checkExistence, checkExistenceOptional, declareAttribute, equals, getAllDeclaredAttributes, getAllMetaAttributes, getAllSubClasses, getAllSuperClasses, getAttribute, getDataSourceURL, getDeclaredAttributes, getDirectSubClasses, getDirectSuperClasses, getInternalIdentifier, getMetaAttribute, getName, getProxyGraphEntityClass, getWrappedGraphEntityClass, hasAttribute, hashCode, isAbstract, isMetaAttributeKeyReserved, isMetaAttributeSet, isSubClassOf, isSuperClassOf, removeSubClass, setMetaAttribute, toString, undeclareAllAttributes, undeclareAttribute, undeclareAttribute, unsetMetaAttribute

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface i3.dragos.gm.core.schema.GraphEntityClass

addSubClass, declareAttribute, equals, getAllDeclaredAttributes, getAllSubClasses, getAllSuperClasses, getAttribute, getDataSourceURL, getDeclaredAttributes, getDirectSubClasses, getDirectSuperClasses, getInternalIdentifier, getName, getWrappedGraphEntityClass, hasAttribute, hashCode, isAbstract, isSubClassOf, isSuperClassOf, removeSubClass, undeclareAllAttributes, undeclareAttribute, undeclareAttribute

Methods inherited from interface i3.dragos.gm.core.schema.MetaAttributable

getAllMetaAttributes, getMetaAttribute, isMetaAttributeKeyReserved, isMetaAttributeSet, setMetaAttribute, unsetMetaAttribute

Methods inherited from interface i3.dragos.gm.core.schema.ExistenceCheckable

checkExistence, checkExistenceOptional

Constructor Detail

RelationClassProxy

public RelationClassProxy(RelationClass e)

Constructs a new wrapper for an relation class.

Parameters:

e - The relation class to wrap.

Method Detail

declareRelationEndClass

public RelationEndClass declareRelationEndClass(java.lang.String name,
                                                GraphEntityClass target,
                                                Cardinality card,
                                                RelationEndDirection direction)
                                         throws EntityNotFoundException,
                                                DragosException,
                                                EntityAlreadyExistsException

Adds a relation end to the relation class.

Specified by:

declareRelationEndClass in interface RelationClass

Parameters:

name - The name of the relation end.

target - The target of the relation end.

card - The cardinality allowed for the target.

direction - The direction of the relation end.

Returns:

the new relation end class.

Throws:

EntityNotFoundException - if the graph element class does not exist.

EntityAlreadyExistsException - if a schema entity with the same name has already been declared.

DragosException - if something else went wrong.

undeclareRelationEndClass

public void undeclareRelationEndClass(RelationEndClass rec)
                               throws EntityNotFoundException,
                                      DragosException

Undeclares a relation end previously declared for the relation class.

It simply performs an additional check whether the RelationEndClass to undeclare really belongs to this RelationClass, throwing an EntityNotFoundException if not. Afterwards, it follows the same procedure as Schema.undeclareGraphEntityClass(GraphEntityClass).

This method could/should be implemented roughly as follows:

 if (! this.equals(rec.getRelationClass())) {
     throw new EntityNotFoundException("RelationEndClass " + rec + " does not belong to " + toString());
 }
 getSchema().undeclareGraphEntityClass(rec);
 

Specified by:

undeclareRelationEndClass in interface RelationClass

Parameters:

rec - The RelationEndClass to undeclare.

Throws:

EntityNotFoundException - if the RelationEndClass does not exist or does not belong to this RelationClass.

DragosException - if something else went wrong.

See Also:

Schema.undeclareGraphEntityClass(GraphEntityClass)

getRelationEndClasses

public java.util.Collection<? extends RelationEndClass> getRelationEndClasses()
                                                                       throws DragosException

Returns a collection with all relation ends of the relation class. The elements of the collection are of type RelationEndClass

Specified by:

getRelationEndClasses in interface RelationClass

Returns:

a collection with all relation ends of the relation class.

Throws:

DragosException - if something went wrong.