001    // Copyright 2006 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.ioc.services;
016    
017    /**
018     * Used by {@link org.apache.tapestry5.ioc.services.LoggingDecorator} to track which exceptions have been logged during
019     * the current request (the ExceptionTracker is perthread). This keeps redundant information from appearing in the
020     * console output.
021     */
022    public interface ExceptionTracker
023    {
024        /**
025         * Returns true if the indicated exception has already been logged (it is assumed that the exception will be logged
026         * if this method returns false). The exception is recorded for later checks.
027         *
028         * @param exception to check
029         * @return false if the exception has not been previously checked, true otherwise
030         */
031        boolean exceptionLogged(Throwable exception);
032    }