/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.isis.viewer.wicket.viewer.imagecache;
import images.Images;
import java.io.IOException;
import java.io.InputStream;
import java.util.Arrays;
import java.util.List;
import java.util.Map;
import com.google.common.collect.Maps;
import com.google.inject.Singleton;
import org.apache.wicket.request.resource.PackageResourceReference;
import org.apache.wicket.request.resource.ResourceReference;
import org.apache.isis.core.metamodel.adapter.ObjectAdapter;
import org.apache.isis.core.metamodel.spec.ObjectSpecification;
import org.apache.isis.viewer.wicket.model.models.ImageResourceCache;
/**
* Caches images loaded up the <tt>images</tt> package (using the {@link Images}
* class).
*
* <p>
* Searches for a fixed set of suffixes: {@value #IMAGE_SUFFICES}.
*/
@Singleton
public class ImageResourceCacheClassPath implements ImageResourceCache {
private static final List<String> IMAGE_SUFFICES = Arrays.asList("png", "gif", "jpeg", "jpg");
private static final String FALLBACK_IMAGE = "Default.png";
private final Map<ObjectSpecification, ResourceReference> resourceReferenceBySpec = Maps.newHashMap();
private PackageResourceReference fallbackResourceReference;
@Override
public ResourceReference resourceReferenceFor(ObjectAdapter adapter) {
String adapterIconName = adapter.getIconName();
if (adapterIconName != null) {
return resourceReferenceFor(adapter.getIconName());
}
return resourceReferenceForSpec(adapter.getSpecification());
}
@Override
public ResourceReference resourceReferenceForSpec(final ObjectSpecification spec) {
if(spec == null) {
return fallbackResourceReference();
}
ResourceReference resourceReference = resourceReferenceBySpec.get(spec);
if(resourceReference != null) {
return resourceReference;
}
resourceReference = lookupResourceReferenceFor(spec);
resourceReferenceBySpec.put(spec, resourceReference);
return resourceReference;
}
private ResourceReference lookupResourceReferenceFor(final ObjectSpecification spec) {
final Class<?> correspondingClass = spec.getCorrespondingClass();
final String specName = correspondingClass.getSimpleName();
final ResourceReference resourceReference = resourceReferenceFor(specName);
if(resourceReference != null) {
return resourceReference;
}
// search up hierarchy
final ObjectSpecification superSpec = spec.superclass();
if(superSpec != null) {
return resourceReferenceForSpec(superSpec);
}
return fallbackResourceReference();
}
private ResourceReference fallbackResourceReference() {
if(fallbackResourceReference == null) {
fallbackResourceReference = newPackageResourceReference(FALLBACK_IMAGE);
}
return fallbackResourceReference;
}
private static ResourceReference resourceReferenceFor(final String specName) {
for(String imageSuffix: IMAGE_SUFFICES) {
final String imageName = specName + "." + imageSuffix;
InputStream resourceAsStream = null;
resourceAsStream = Images.class.getResourceAsStream(imageName);
if(resourceAsStream == null) {
continue;
} else {
closeSafely(resourceAsStream);
}
return newPackageResourceReference(imageName);
}
return null;
}
private static PackageResourceReference newPackageResourceReference(final String imageFile) {
return new PackageResourceReference(Images.class, imageFile);
}
private static void closeSafely(InputStream resourceAsStream) {
try {
resourceAsStream.close();
} catch (IOException e) {
// ignore
}
}
}