001    // Copyright 2009 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.services;
016    
017    import org.apache.tapestry5.ioc.annotations.UsesOrderedConfiguration;
018    
019    /**
020     * Used by {@link org.apache.tapestry5.corelib.components.ExceptionDisplay} to characterize each stack frame that is
021     * presented.  Implemented as a chain-of-command service.
022     *
023     * @since 5.1.0.0
024     */
025    @UsesOrderedConfiguration(StackTraceElementAnalyzer.class)
026    public interface StackTraceElementAnalyzer
027    {
028        /**
029         * Returns the CSS class appropriate to the frame.
030         *
031         * @param frame stack trace element to be analyzed
032         * @return the CSS class name, or null
033         */
034        String classForFrame(StackTraceElement frame);
035    }