001    // Copyright 2004, 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.junit.mock.c21;
016    
017    import org.apache.tapestry.engine.IPropertySource;
018    
019    /**
020     * Empty implementation just to exercise some code paths in
021     * {@link org.apache.tapestry.engine.AbstractEngine}.
022     * 
023     * @author Howard Lewis Ship
024     * @since 3.0
025     */
026    
027    public class NullPropertySource implements IPropertySource
028    {
029    
030        public String getPropertyValue(String propertyName)
031        {
032            return null;
033        }
034    
035    }