// Copyright 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.lang.reflect.Modifier;
import org.apache.tapestry5.annotations.Property;
import org.apache.tapestry5.ioc.internal.util.InternalUtils;
import org.apache.tapestry5.model.MutableComponentModel;
import org.apache.tapestry5.services.ClassTransformation;
import org.apache.tapestry5.services.ComponentClassTransformWorker;
import org.apache.tapestry5.services.ComponentMethodAdvice;
import org.apache.tapestry5.services.ComponentMethodInvocation;
import org.apache.tapestry5.services.FieldAccess;
import org.apache.tapestry5.services.TransformField;
import org.apache.tapestry5.services.TransformMethodSignature;
/**
* Provides the getter and setter methods. The methods are added as "existing", meaning that field access to them will
* be transformed as necessary by other annotations. This worker needs to be scheduled before any worker that might
* delete a field.
*
* @see org.apache.tapestry5.annotations.Property
*/
public class PropertyWorker implements ComponentClassTransformWorker
{
public void transform(ClassTransformation transformation, MutableComponentModel model)
{
for (TransformField field : transformation.matchFieldsWithAnnotation(Property.class))
{
createAccessorsForField(transformation, field);
}
}
private void createAccessorsForField(ClassTransformation transformation, TransformField field)
{
Property annotation = field.getAnnotation(Property.class);
String propertyName = InternalUtils.capitalize(InternalUtils.stripMemberName(field.getName()));
if (annotation.read())
addGetter(transformation, field, propertyName);
if (annotation.write())
addSetter(transformation, field, propertyName);
}
private void addSetter(ClassTransformation transformation, TransformField field, String propertyName)
{
TransformMethodSignature setter = new TransformMethodSignature(Modifier.PUBLIC, "void", "set" + propertyName,
new String[]
{ field.getType() }, null);
ensureNotOverride(transformation, setter);
final FieldAccess access = field.getAccess();
transformation.getOrCreateMethod(setter).addAdvice(new ComponentMethodAdvice()
{
public void advise(ComponentMethodInvocation invocation)
{
access.write(invocation.getInstance(), invocation.getParameter(0));
}
});
}
private void ensureNotOverride(ClassTransformation transformation, TransformMethodSignature signature)
{
if (transformation.isDeclaredMethod(signature))
throw new RuntimeException(String.format(
"Unable to create new method %s as it already exists in class %s.", signature, transformation
.getClassName()));
}
private void addGetter(ClassTransformation transformation, TransformField field, String propertyName)
{
TransformMethodSignature getter = new TransformMethodSignature(Modifier.PUBLIC, field.getType(), "get"
+ propertyName, null, null);
ensureNotOverride(transformation, getter);
final FieldAccess access = field.getAccess();
transformation.getOrCreateMethod(getter).addAdvice(new ComponentMethodAdvice()
{
public void advise(ComponentMethodInvocation invocation)
{
invocation.overrideResult(access.read(invocation.getInstance()));
}
});
}
}