/*
* 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 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;
import images.Images;
/**
* Caches images loaded either from the same package as the specified object, or from the <tt>images</tt> package (using the {@link Images} otherwise.
* class).
*
* <p>
* Searches for a fixed set of suffixes: <code>png, gif, jpeg, jpg, svg</code>.
*/
@Singleton
public class ImageResourceCacheClassPath implements ImageResourceCache {
private static final long serialVersionUID = 1L;
private static final List<String> IMAGE_SUFFICES = Arrays.asList("png", "gif", "jpeg", "jpg", "svg");
private static final String FALLBACK_IMAGE = "Default.png";
private final Map<ImageResourceCacheKey, ResourceReference> resourceReferenceByKey = Maps.newConcurrentMap();
private final PackageResourceReference fallbackResource;
public ImageResourceCacheClassPath() {
fallbackResource = new PackageResourceReference(Images.class, FALLBACK_IMAGE);
resourceReferenceByKey.put(new ImageResourceCacheKey(null, null), fallbackResource);
}
@Override
public ResourceReference resourceReferenceFor(final ObjectAdapter adapter) {
return resourceReferenceFor(adapter.getSpecification(), adapter.getIconName());
}
@Override
public ResourceReference resourceReferenceForSpec(final ObjectSpecification spec) {
return resourceReferenceFor(spec, null);
}
private ResourceReference resourceReferenceFor(
final ObjectSpecification specification,
final String iconNameIfAny) {
final Class<?> correspondingClassIfAny = specification != null? specification.getCorrespondingClass(): null;
final ImageResourceCacheKey key = new ImageResourceCacheKey(correspondingClassIfAny, iconNameIfAny);
ResourceReference resourceReference = resourceReferenceByKey.get(key);
if(resourceReference == null) {
resourceReference = findResourceReferenceFor(key);
resourceReferenceByKey.put(key, resourceReference);
}
return resourceReference;
}
protected ResourceReference findResourceReferenceFor(final ImageResourceCacheKey key) {
final List<ImageResourceCacheKey> keys = key.resourcePaths(IMAGE_SUFFICES);
for (ImageResourceCacheKey resourceKey : keys) {
Class<?> resourceClass = resourceKey.getResourceClass();
if(resourceClass == null) {
resourceClass = Images.class;
}
final String iconName = resourceKey.getResourceName();
final InputStream resourceAsStream = resourceClass.getResourceAsStream(iconName);
if (resourceAsStream != null) {
closeSafely(resourceAsStream);
return new PackageResourceReference(resourceClass, iconName);
}
}
return fallbackResource;
}
private static void closeSafely(InputStream resourceAsStream) {
try {
resourceAsStream.close();
} catch (IOException e) {
// ignore
}
}
}