// Copyright 2006, 2007 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.tapestry.internal.transform;
import org.apache.tapestry.annotations.InjectPage;
import org.apache.tapestry.internal.services.RequestPageCache;
import org.apache.tapestry.internal.structure.Page;
import org.apache.tapestry.ioc.internal.util.InternalUtils;
import org.apache.tapestry.ioc.util.BodyBuilder;
import org.apache.tapestry.model.MutableComponentModel;
import org.apache.tapestry.services.ClassTransformation;
import org.apache.tapestry.services.ComponentClassResolver;
import org.apache.tapestry.services.ComponentClassTransformWorker;
import org.apache.tapestry.services.TransformMethodSignature;
import java.lang.reflect.Modifier;
import java.util.List;
/**
* Peforms transformations that allow pages to be injected into components.
*
* @see org.apache.tapestry.annotations.InjectPage
*/
public class InjectPageWorker implements ComponentClassTransformWorker
{
private final RequestPageCache _requestPageCache;
private final ComponentClassResolver _resolver;
public InjectPageWorker(RequestPageCache requestPageCache, ComponentClassResolver resolver)
{
_requestPageCache = requestPageCache;
_resolver = resolver;
}
public void transform(ClassTransformation transformation, MutableComponentModel model)
{
List<String> names = transformation.findFieldsWithAnnotation(InjectPage.class);
if (names.isEmpty()) return;
String cacheFieldName = transformation.addInjectedField(RequestPageCache.class, "_requestPageCache",
_requestPageCache);
for (String name : names)
addInjectedPage(transformation, name, cacheFieldName);
}
private void addInjectedPage(ClassTransformation transformation, String fieldName, String cacheFieldName)
{
InjectPage annotation = transformation.getFieldAnnotation(fieldName, InjectPage.class);
String pageName = annotation.value();
String fieldType = transformation.getFieldType(fieldName);
String methodName = transformation.newMemberName("read_inject_page", fieldName);
String injectedPageName = InternalUtils.isBlank(pageName) ? _resolver
.resolvePageClassNameToPageName(fieldType) : pageName;
TransformMethodSignature sig = new TransformMethodSignature(Modifier.PRIVATE, fieldType, methodName, null,
null);
BodyBuilder builder = new BodyBuilder();
builder.begin();
builder.addln("%s page = %s.get(\"%s\");", Page.class.getName(), cacheFieldName, injectedPageName);
builder.addln("return (%s) page.getRootElement().getComponent();", fieldType);
builder.end();
transformation.addMethod(sig, builder.toString());
transformation.replaceReadAccess(fieldName, methodName);
transformation.makeReadOnly(fieldName);
transformation.removeField(fieldName);
transformation.claimField(fieldName, annotation);
}
}