// 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.services;
import org.apache.tapestry5.Asset;
import org.apache.tapestry5.ComponentResources;
import org.apache.tapestry5.annotations.Path;
import org.apache.tapestry5.ioc.ObjectLocator;
import org.apache.tapestry5.model.MutableComponentModel;
import org.apache.tapestry5.plastic.ComputedValue;
import org.apache.tapestry5.plastic.InstanceContext;
import org.apache.tapestry5.plastic.PlasticField;
import org.apache.tapestry5.services.AssetSource;
import org.apache.tapestry5.services.transform.InjectionProvider2;
/**
* Performs injection of assets, based on the presence of the {@link Path} annotation. This is more
* useful than the
* general {@link AssetObjectProvider}, because relative assets are supported.
*/
public class AssetInjectionProvider implements InjectionProvider2
{
private final AssetSource assetSource;
public AssetInjectionProvider(AssetSource assetSource)
{
this.assetSource = assetSource;
}
public boolean provideInjection(PlasticField field, ObjectLocator locator, MutableComponentModel componentModel)
{
Path path = field.getAnnotation(Path.class);
if (path == null)
{
return false;
}
final String assetPath = path.value();
final String libraryName = componentModel.getLibraryName();
ComputedValue<Asset> computedAsset = new ComputedValue<Asset>()
{
public Asset get(InstanceContext context)
{
ComponentResources resources = context.get(ComponentResources.class);
// Note how this works: the resources represents the actual instantiated class, and the libraryName
// comes from the componentModel, potentially, the componentModel of a base class (which may have
// a different library name than the subclass).
return assetSource.getComponentAsset(resources, assetPath, libraryName);
}
};
field.injectComputed(computedAsset);
return true;
}
}