// Copyright 2006, 2007, 2008, 2010 The Apache Software Foundation
//
// 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.apache.tapestry5.internal.transform;
import org.apache.tapestry5.ComponentResources;
import org.apache.tapestry5.annotations.Environmental;
import org.apache.tapestry5.internal.services.ComponentClassCache;
import org.apache.tapestry5.ioc.services.FieldValueConduit;
import org.apache.tapestry5.model.MutableComponentModel;
import org.apache.tapestry5.services.ClassTransformation;
import org.apache.tapestry5.services.ComponentClassTransformWorker;
import org.apache.tapestry5.services.ComponentValueProvider;
import org.apache.tapestry5.services.Environment;
import org.apache.tapestry5.services.TransformField;
/**
* Obtains a value from the {@link Environment} service based on the field type. This is triggered by the presence of
* the {@link Environmental} annotation.
*/
@SuppressWarnings("rawtypes")
public class EnvironmentalWorker implements ComponentClassTransformWorker
{
private final Environment environment;
private final ComponentClassCache classCache;
@SuppressWarnings("unchecked")
private final class EnvironmentalConduit extends ReadOnlyFieldValueConduit
{
private final Class environmentalType;
private final boolean required;
private EnvironmentalConduit(ComponentResources resources, String fieldName, final Class environmentalType,
boolean required)
{
super(resources, fieldName);
this.environmentalType = environmentalType;
this.required = required;
}
public Object get()
{
return required ? environment.peekRequired(environmentalType) : environment.peek(environmentalType);
}
}
public EnvironmentalWorker(Environment environment, ComponentClassCache classCache)
{
this.environment = environment;
this.classCache = classCache;
}
public void transform(ClassTransformation transformation, MutableComponentModel model)
{
for (TransformField field : transformation.matchFieldsWithAnnotation(Environmental.class))
{
transform(field);
}
}
private void transform(TransformField field)
{
Environmental annotation = field.getAnnotation(Environmental.class);
field.claim(annotation);
final String fieldName = field.getName();
final Class fieldType = classCache.forName(field.getType());
final boolean required = annotation.value();
ComponentValueProvider<FieldValueConduit> provider = new ComponentValueProvider<FieldValueConduit>()
{
public FieldValueConduit get(ComponentResources resources)
{
return new EnvironmentalConduit(resources, fieldName, fieldType, required);
}
};
field.replaceAccess(provider);
}
}