| /* |
| * 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.felix.ipojo.manipulator.metadata; |
| |
| import java.io.IOException; |
| import java.util.ArrayList; |
| import java.util.List; |
| |
| import org.apache.felix.ipojo.manipulator.MetadataProvider; |
| import org.apache.felix.ipojo.metadata.Element; |
| |
| /** |
| * A {@code CacheableMetadataProvider} provides simple caching methods to avoid |
| * calling {@link MetadataProvider#getMetadatas()} twice. |
| * |
| * TODO Do we really need this ? ATM it is not used ... |
| * |
| * @author <a href="mailto:dev@felix.apache.org">Felix Project Team</a> |
| */ |
| public class CacheableMetadataProvider implements MetadataProvider { |
| |
| /** |
| * Delegate. |
| */ |
| private MetadataProvider m_delegate; |
| |
| /** |
| * Cached elements. |
| */ |
| private List<Element> m_cached; |
| |
| public CacheableMetadataProvider(MetadataProvider delegate) { |
| m_delegate = delegate; |
| } |
| |
| public List<Element> getMetadatas() throws IOException { |
| |
| // Only ask the delegate if cache is empty |
| if (m_cached == null) { |
| m_cached = new ArrayList<Element>(); |
| m_cached.addAll(m_delegate.getMetadatas()); |
| } |
| return m_cached; |
| } |
| } |