| /* |
| * Copyright 2011-2012 Niclas Hedhman. |
| * Copyright 2014 Paul Merlin. |
| * |
| * 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 |
| * ied. |
| * |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.qi4j.api.query.grammar; |
| |
| import java.lang.reflect.AccessibleObject; |
| import java.lang.reflect.Member; |
| import java.lang.reflect.Proxy; |
| import org.qi4j.api.association.AssociationStateHolder; |
| import org.qi4j.api.association.NamedAssociation; |
| import org.qi4j.api.composite.Composite; |
| import org.qi4j.api.composite.CompositeInstance; |
| import org.qi4j.functional.Function; |
| |
| /** |
| * Function to get Entity NamedAssociations. |
| */ |
| public class NamedAssociationFunction<T> |
| implements Function<Composite, NamedAssociation<T>> |
| { |
| private final AssociationFunction<?> traversedAssociation; |
| private final ManyAssociationFunction<?> traversedManyAssociation; |
| private final NamedAssociationFunction<?> traversedNamedAssociation; |
| private final AccessibleObject accessor; |
| |
| public NamedAssociationFunction( AssociationFunction<?> traversedAssociation, |
| ManyAssociationFunction<?> traversedManyAssociation, |
| NamedAssociationFunction<?> traversedNamedAssociation, |
| AccessibleObject accessor |
| ) |
| { |
| this.traversedAssociation = traversedAssociation; |
| this.traversedManyAssociation = traversedManyAssociation; |
| this.traversedNamedAssociation = traversedNamedAssociation; |
| this.accessor = accessor; |
| } |
| |
| public AssociationFunction<?> traversedAssociation() |
| { |
| return traversedAssociation; |
| } |
| |
| public ManyAssociationFunction<?> traversedManyAssociation() |
| { |
| return traversedManyAssociation; |
| } |
| |
| public NamedAssociationFunction<?> traversedNamedAssociation() |
| { |
| return traversedNamedAssociation; |
| } |
| |
| public AccessibleObject accessor() |
| { |
| return accessor; |
| } |
| |
| @Override |
| public NamedAssociation<T> map( Composite entity ) |
| { |
| try |
| { |
| Object target = entity; |
| if( traversedAssociation != null ) |
| { |
| target = traversedAssociation.map( entity ).get(); |
| } |
| if( traversedManyAssociation != null ) |
| { |
| throw new IllegalArgumentException( "Cannot traverse ManyAssociations" ); |
| } |
| if( traversedNamedAssociation != null ) |
| { |
| throw new IllegalArgumentException( "Cannot traverse NamedAssociations" ); |
| } |
| |
| CompositeInstance handler = (CompositeInstance) Proxy.getInvocationHandler( target ); |
| return ( (AssociationStateHolder) handler.state() ).namedAssociationFor( accessor ); |
| } |
| catch( IllegalArgumentException e ) |
| { |
| throw e; |
| } |
| catch( Throwable e ) |
| { |
| throw new IllegalArgumentException( e ); |
| } |
| } |
| |
| @Override |
| public String toString() |
| { |
| if( traversedAssociation != null ) |
| { |
| return traversedAssociation.toString() + "." + ( (Member) accessor ).getName(); |
| } |
| else |
| { |
| return ( (Member) accessor ).getName(); |
| } |
| } |
| } |