001    // Copyright 2008, 2010 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.tapestry5.internal;
016    
017    import org.apache.tapestry5.EventContext;
018    
019    /**
020     * Placeholder used when no context is available.
021     */
022    public class EmptyEventContext implements EventContext
023    {
024        /**
025         * Always returns zero.
026         */
027        public int getCount()
028        {
029            return 0;
030        }
031    
032        /**
033         * This should never be called because the count is always zero.
034         */
035        public <T> T get(Class<T> desiredType, int index)
036        {
037            return null;
038        }
039    
040        public String[] toStrings()
041        {
042            return InternalConstants.EMPTY_STRING_ARRAY;
043        }
044    }