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A collection of classes shared by broadleaf profile, cms, admin, and core.
/*
* #%L
* BroadleafCommerce Common Libraries
* %%
* Copyright (C) 2009 - 2013 Broadleaf Commerce
* %%
* 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.
* #L%
*/
package org.broadleafcommerce.common.web.resource;
import net.sf.ehcache.Cache;
import net.sf.ehcache.CacheManager;
import net.sf.ehcache.Element;
import org.apache.commons.io.IOUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.broadleafcommerce.common.cache.CacheStatType;
import org.broadleafcommerce.common.cache.StatisticsService;
import org.broadleafcommerce.common.extension.ExtensionResultHolder;
import org.broadleafcommerce.common.resource.GeneratedResource;
import org.broadleafcommerce.common.util.StreamingTransactionCapableUtil;
import org.springframework.core.Ordered;
import org.springframework.core.io.Resource;
import java.io.IOException;
import java.io.StringWriter;
import java.util.List;
/**
* An abstract GeneratedResourceHandler that is capable of responding to a single specified filename and generate
* contents for that filename. This abstract parent will handle caching of the generated resource.
*
* @author Andre Azzolini (apazzolini)
*
*/
public abstract class AbstractGeneratedResourceHandler implements Ordered {
public static final int DEFAULT_ORDER = 10000;
protected static final Log LOG = LogFactory.getLog(AbstractGeneratedResourceHandler.class);
@javax.annotation.Resource(name="blStatisticsService")
protected StatisticsService statisticsService;
@javax.annotation.Resource(name="blStreamingTransactionCapableUtil")
protected StreamingTransactionCapableUtil transUtil;
@javax.annotation.Resource(name = "blResourceRequestExtensionManager")
protected ResourceRequestExtensionManager extensionManager;
protected Cache generatedResourceCache;
/**
* @param path
* @return booelean determining whether or not this handler is able to handle the given request
*/
public abstract boolean canHandle(String path);
/**
* @param path
* @param locations
* @return the Resource representing this file
*/
public abstract Resource getFileContents(String path, List locations);
/**
* @param cachedResource
* @param path
* @param locations
* @return whether or not the given cachedResource needs to be regenerated
*/
public abstract boolean isCachedResourceExpired(GeneratedResource cachedResource, String path, List locations);
/**
* Attempts to retrive the requested resource from cache. If not cached, generates the resource, caches it,
* and then returns it
*
* @param request
* @param location
* @return the generated resource
*/
public Resource getResource(final String path, final List locations) {
Element e = getGeneratedResourceCache().get(path);
Resource r = null;
if (e == null) {
statisticsService.addCacheStat(CacheStatType.GENERATED_RESOURCE_CACHE_HIT_RATE.toString(), false);
} else {
statisticsService.addCacheStat(CacheStatType.GENERATED_RESOURCE_CACHE_HIT_RATE.toString(), true);
}
boolean shouldGenerate = false;
if (e == null || e.getObjectValue() == null) {
shouldGenerate = true;
} else if (e.getObjectValue() instanceof GeneratedResource
&& isCachedResourceExpired((GeneratedResource) e.getObjectValue(), path, locations)) {
shouldGenerate = true;
} else {
r = (Resource) e.getObjectValue();
}
if (shouldGenerate) {
r = getFileContents(path, locations);
e = new Element(path, r);
getGeneratedResourceCache().put(e);
}
return r;
}
/**
* This method can be used to read in a resource given a path and at least one resource location
*
* @param path
* @param locations
* @return the resource from the file system, classpath, etc, if it exists
*/
protected Resource getRawResource(String path, List locations) {
ExtensionResultHolder erh = new ExtensionResultHolder();
extensionManager.getProxy().getOverrideResource(path, erh);
if (erh.getContextMap().get(ResourceRequestExtensionHandler.RESOURCE_ATTR) != null) {
return (Resource) erh.getContextMap().get(ResourceRequestExtensionHandler.RESOURCE_ATTR);
}
for (Resource location : locations) {
try {
Resource resource = location.createRelative(path);
if (resource.exists() && resource.isReadable()) {
return resource;
}
}
catch (IOException ex) {
LOG.debug("Failed to create relative resource - trying next resource location", ex);
}
}
return null;
}
/**
* @param resource
* @return the UTF-8 String represetation of the contents of the resource
*/
protected String getResourceContents(Resource resource) throws IOException {
StringWriter writer = null;
try {
writer = new StringWriter();
IOUtils.copy(resource.getInputStream(), writer, "UTF-8");
return writer.toString();
} finally {
if (writer != null) {
writer.flush();
writer.close();
}
}
}
protected Cache getGeneratedResourceCache() {
if (generatedResourceCache == null) {
generatedResourceCache = CacheManager.getInstance().getCache("generatedResourceCache");
}
return generatedResourceCache;
}
@Override
public int getOrder() {
return DEFAULT_ORDER;
}
}