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
015package 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 */
022public 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}