// Copyright 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 java.util.List;
import java.util.Map;
import java.util.TreeMap;
import org.apache.tapestry5.annotations.ApplicationState;
import org.apache.tapestry5.annotations.SessionState;
import org.apache.tapestry5.func.Predicate;
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.ApplicationStateManager;
import org.apache.tapestry5.services.ClassTransformation;
import org.apache.tapestry5.services.ComponentClassTransformWorker;
import org.apache.tapestry5.services.TransformField;
/**
* Looks for the {@link ApplicationState} and {@link org.apache.tapestry5.annotations.SessionState} annotations and
* converts read and write access on such fields into calls to the {@link ApplicationStateManager}.
*/
public class ApplicationStateWorker implements ComponentClassTransformWorker
{
private final ApplicationStateManager applicationStateManager;
private final ComponentClassCache componentClassCache;
public ApplicationStateWorker(ApplicationStateManager applicationStateManager,
ComponentClassCache componentClassCache)
{
this.applicationStateManager = applicationStateManager;
this.componentClassCache = componentClassCache;
}
public void transform(ClassTransformation transformation, MutableComponentModel model)
{
Map<TransformField, Boolean> fields = new TreeMap<TransformField, Boolean>();
for (TransformField field : transformation.matchFieldsWithAnnotation(ApplicationState.class))
{
ApplicationState annotation = field.getAnnotation(ApplicationState.class);
fields.put(field, annotation.create());
field.claim(annotation);
}
for (TransformField field : transformation.matchFieldsWithAnnotation(SessionState.class))
{
SessionState annotation = field.getAnnotation(SessionState.class);
fields.put(field, annotation.create());
field.claim(annotation);
}
for (Map.Entry<TransformField, Boolean> e : fields.entrySet())
{
transform(transformation, e.getKey(), e.getValue());
}
}
@SuppressWarnings("unchecked")
private void transform(ClassTransformation transformation, TransformField field, final boolean create)
{
final Class fieldClass = componentClassCache.forName(field.getType());
field.replaceAccess(new FieldValueConduit()
{
public void set(Object newValue)
{
applicationStateManager.set(fieldClass, newValue);
}
public Object get()
{
return create ? applicationStateManager.get(fieldClass) : applicationStateManager
.getIfExists(fieldClass);
}
});
final String expectedName = field.getName() + "Exists";
List<TransformField> fields = transformation.matchFields(new Predicate<TransformField>()
{
public boolean accept(TransformField field)
{
return field.getType().equals("boolean") && field.getName().equalsIgnoreCase(expectedName);
}
});
for (TransformField existsField : fields)
{
existsField.claim(this);
String className = transformation.getClassName();
String fieldName = existsField.getName();
existsField.replaceAccess(new ReadOnlyFieldValueConduit(className, fieldName)
{
public Object get()
{
return applicationStateManager.exists(fieldClass);
}
});
}
}
}