| /* |
| * 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.sling.fsprovider.internal.parser; |
| |
| import java.io.File; |
| import java.util.Collections; |
| import java.util.Map; |
| |
| import org.apache.commons.collections.map.LRUMap; |
| |
| /** |
| * Cache for parsed content from content files (e.g. JSON, JCR XML). |
| */ |
| public final class ContentFileCache { |
| |
| private final Map<String,ContentElement> contentCache; |
| private final ContentElement NULL_ELEMENT = new ContentElementImpl(null, Collections.<String,Object>emptyMap()); |
| |
| /** |
| * @param maxSize Cache size. 0 = caching disabled. |
| */ |
| @SuppressWarnings("unchecked") |
| public ContentFileCache(int maxSize) { |
| if (maxSize > 0) { |
| this.contentCache = Collections.synchronizedMap(new LRUMap(maxSize)); |
| } |
| else { |
| this.contentCache = null; |
| } |
| } |
| |
| /** |
| * Get content. |
| * @param path Path (used as cache key). |
| * @param file File |
| * @return Content or null |
| */ |
| public ContentElement get(String path, File file) { |
| ContentElement content = null; |
| if (contentCache != null) { |
| content = contentCache.get(path); |
| } |
| if (content == null) { |
| content = ContentFileParserUtil.parse(file); |
| if (content == null) { |
| content = NULL_ELEMENT; |
| } |
| if (contentCache != null) { |
| contentCache.put(path, content); |
| } |
| } |
| if (content == NULL_ELEMENT) { |
| return null; |
| } |
| else { |
| return content; |
| } |
| } |
| |
| /** |
| * Remove content from cache. |
| * @param path Path (used as cache key) |
| */ |
| public void remove(String path) { |
| if (contentCache != null) { |
| contentCache.remove(path); |
| } |
| } |
| |
| /** |
| * Clear whole cache |
| */ |
| public void clear() { |
| if (contentCache != null) { |
| contentCache.clear(); |
| } |
| } |
| |
| /** |
| * @return Current cache size |
| */ |
| public int size() { |
| if (contentCache != null) { |
| return contentCache.size(); |
| } |
| else { |
| return 0; |
| } |
| } |
| |
| } |