001    /**
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    package org.apache.camel.blueprint;
018    
019    import java.util.Properties;
020    
021    import org.apache.camel.CamelContext;
022    import org.apache.camel.component.properties.PropertiesResolver;
023    import org.apache.camel.util.ObjectHelper;
024    
025    /**
026     * A {@link PropertiesResolver} which supports the <tt>blueprint</tt> scheme.
027     * <p/>
028     * This implementation will sit on top of any existing configured
029     * {@link org.apache.camel.component.properties.PropertiesResolver} and will delegate
030     * to any non <tt>blueprint</tt> schemes.
031     */
032    public class BlueprintPropertiesResolver implements PropertiesResolver {
033    
034        private final PropertiesResolver delegate;
035        private final BlueprintPropertiesParser blueprint;
036    
037        public BlueprintPropertiesResolver(PropertiesResolver delegate, BlueprintPropertiesParser blueprint) {
038            this.delegate = delegate;
039            this.blueprint = blueprint;
040        }
041    
042        @Override
043        public Properties resolveProperties(CamelContext context, String... urls) throws Exception {
044            Properties answer = new Properties();
045    
046            boolean explicit = false;
047    
048            for (String url : urls) {
049                if (url.startsWith("blueprint:")) {
050                    String ref = ObjectHelper.after(url, "blueprint:");
051                    blueprint.addPropertyPlaceholder(ref);
052                    // indicate an explicit blueprint id was configured
053                    explicit = true;
054                } else {
055                    // delegate the url
056                    answer.putAll(delegate.resolveProperties(context, url));
057                }
058            }
059    
060            if (!explicit) {
061                // auto lookup blueprint property placeholders to use if none explicit was configured
062                // this is convention over configuration
063                String[] ids = blueprint.lookupPropertyPlaceholderIds();
064                for (String id : ids) {
065                    blueprint.addPropertyPlaceholder(id);
066                }
067            }
068    
069            return answer;
070        }
071    
072    }