/*
* Copyright 2007, Rickard Öberg.
* Copyright 2009, Niclas Hedhman.
* Copyright 2012, Kent Sølvsten.
* Copyright 2013, 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
* implied.
*
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.qi4j.runtime.value;
import org.qi4j.api.association.AssociationStateHolder;
import org.qi4j.api.common.ConstructionException;
import org.qi4j.api.value.ValueBuilder;
import org.qi4j.api.value.ValueComposite;
import org.qi4j.api.value.ValueSerialization;
import org.qi4j.api.value.ValueSerializationException;
import org.qi4j.runtime.structure.ModelModule;
import org.qi4j.runtime.structure.ModuleInstance;
/**
* Implementation of ValueBuilder with a prototype supplied
*/
public class ValueBuilderWithPrototype<T>
implements ValueBuilder<T>
{
private ValueInstance prototypeInstance;
private final ValueModel valueModel;
public ValueBuilderWithPrototype(ModelModule<ValueModel> compositeModelModule, ModuleInstance currentModule, T prototype)
{
valueModel = compositeModelModule.model();
// Use serialization-deserialization to make a copy of the prototype
final Object value;
try
{
// @TODO there is probably a more efficient way to do this
ValueSerialization valueSerialization = currentModule.valueSerialization();
String serialized = valueSerialization.serialize( prototype );
value = valueSerialization.deserialize( valueModel.valueType(), serialized);
}
catch( ValueSerializationException e )
{
throw new IllegalStateException( "Could not serialize-copy Value", e );
}
ValueInstance valueInstance = ValueInstance.valueInstanceOf( (ValueComposite) value );
valueInstance.prepareToBuild();
this.prototypeInstance = valueInstance;
}
@Override
public T prototype()
{
verifyUnderConstruction();
return prototypeInstance.<T>proxy();
}
@Override
public AssociationStateHolder state()
{
verifyUnderConstruction();
return prototypeInstance.state();
}
@Override
public <K> K prototypeFor( Class<K> mixinType )
{
verifyUnderConstruction();
return prototypeInstance.newProxy( mixinType );
}
@Override
public T newInstance()
throws ConstructionException
{
verifyUnderConstruction();
// Set correct info's (immutable) on the state
prototypeInstance.prepareBuilderState();
// Check that it is valid
valueModel.checkConstraints( prototypeInstance.state() );
try
{
return prototypeInstance.<T>proxy();
}
finally
{
// Invalidate builder
prototypeInstance = null;
}
}
private void verifyUnderConstruction()
{
if( prototypeInstance == null )
{
throw new IllegalStateException( "ValueBuilder instances cannot be reused" );
}
}
}