001    // Copyright 2005 The Apache Software Foundation
002    //
003    // Licensed under the Apache License, Version 2.0 (the "License");
004    // you may not use this file except in compliance with the License.
005    // You may obtain a copy of the License at
006    //
007    //     http://www.apache.org/licenses/LICENSE-2.0
008    //
009    // Unless required by applicable law or agreed to in writing, software
010    // distributed under the License is distributed on an "AS IS" BASIS,
011    // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012    // See the License for the specific language governing permissions and
013    // limitations under the License.
014    
015    package org.apache.tapestry.pageload;
016    
017    import org.apache.tapestry.INamespace;
018    import org.apache.tapestry.services.ClassFinder;
019    
020    /**
021     * Searches for a class with a name matching the page name. Searches in the
022     * default Java package, and possibly additional packages defined as meta-data
023     * within the namespace.
024     * 
025     * @author Howard M. Lewis Ship
026     * @since 4.0
027     */
028    public class NamespaceClassSearchComponentClassProvider implements
029            ComponentClassProvider
030    {
031    
032        /**
033         * Property, defined as meta data of the containing namespace, that defines
034         * a comma-seperated list of packages to search for page or component
035         * classes within.
036         */
037        private String _packagesName;
038    
039        private ClassFinder _classFinder;
040    
041        public String provideComponentClassName(
042                ComponentClassProviderContext context)
043        {
044            INamespace namespace = context.getNamespace();
045            String packages = namespace.getPropertyValue(_packagesName);
046    
047            String componentClassName = context.getName().replace('/', '.');
048    
049            Class clazz = _classFinder.findClass(packages, componentClassName);
050    
051            return clazz == null ? null : clazz.getName();
052        }
053    
054        public void setPackagesName(String packagesName)
055        {
056            _packagesName = packagesName;
057        }
058    
059        public void setClassFinder(ClassFinder classFinder)
060        {
061            _classFinder = classFinder;
062        }
063    }