/*
* Copyright (c) 2007, Rickard Öberg. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
package org.qi4j.runtime.association;
import java.lang.reflect.Type;
import org.qi4j.api.association.Association;
import org.qi4j.api.association.AssociationDescriptor;
import org.qi4j.api.association.AssociationWrapper;
import org.qi4j.api.entity.EntityReference;
import org.qi4j.api.property.Property;
import org.qi4j.functional.Function2;
/**
* Implementation of Association to a single Entity.
*/
public final class AssociationInstance<T>
extends AbstractAssociationInstance<T>
implements Association<T>
{
private Property<EntityReference> associationState;
public AssociationInstance( AssociationInfo associationInfo,
Function2<EntityReference, Type, Object> entityFunction,
Property<EntityReference> associationState
)
{
super( associationInfo, entityFunction );
this.associationState = associationState;
}
// Association implementation
@Override
public T get()
{
return getEntity( associationState.get() );
}
@Override
public void set( T newValue )
throws IllegalArgumentException
{
checkImmutable();
checkType( newValue );
associationInfo.checkConstraints( newValue );
// Change association
associationState.set( getEntityReference( newValue ) );
}
public Property<EntityReference> getAssociationState()
{
return associationState;
}
@Override
public String toString()
{
if( associationState.get() == null )
{
return "";
}
else
{
return associationState.get().toString();
}
}
@Override
public int hashCode()
{
int hash = associationInfo.hashCode() * 61; // Descriptor
if( associationState.get() != null )
{
hash += associationState.get().hashCode() * 3; // State
}
return hash;
}
@Override
public boolean equals( Object o )
{
if( this == o )
{
return true;
}
if( o == null || getClass() != o.getClass() )
{
return false;
}
Association<?> that = (Association) o;
// Unwrap if needed
while( that instanceof AssociationWrapper )
{
that = ( (AssociationWrapper) that ).next();
}
// Descriptor equality
AssociationInstance<?> thatInstance = (AssociationInstance) that;
AssociationDescriptor thatDescriptor = (AssociationDescriptor) thatInstance.associationInfo();
if( !associationInfo.equals( thatDescriptor ) )
{
return false;
}
// State equality
if( associationState.get() != null
? !associationState.get().equals( thatInstance.associationState.get() )
: thatInstance.associationState.get() != null )
{
return false;
}
return true;
}
}