001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache license, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the license for the specific language governing permissions and
015 * limitations under the license.
016 */
017package org.apache.logging.log4j.core.filter;
018
019import org.apache.logging.log4j.core.Filter;
020import org.apache.logging.log4j.core.LifeCycle;
021import org.apache.logging.log4j.core.LogEvent;
022
023/**
024 * Interface implemented by Classes that allow filtering to occur.
025 *
026 * <p>
027 * Extends {@link LifeCycle} since filters have a life cycle.
028 * </p>
029 */
030public interface Filterable extends LifeCycle {
031
032    /**
033     * Adds a new Filter. If a Filter already exists it is converted to a CompositeFilter.
034     * @param filter The Filter to add.
035     */
036    void addFilter(Filter filter);
037
038    /**
039     * Removes a Filter.
040     * @param filter The Filter to remove.
041     */
042    void removeFilter(Filter filter);
043
044    /**
045     * Returns an Iterator for all the Filters.
046     * @return an Iterator for all the Filters.
047     */
048    Filter getFilter();
049
050    /**
051     * Determine if a Filter is present.
052     * @return true if a Filter is present, false otherwise.
053     */
054    boolean hasFilter();
055
056    /**
057     * Determines if the event should be filtered.
058     * @param event The LogEvent.
059     * @return true if the event should be filtered, false otherwise.
060     */
061    boolean isFiltered(LogEvent event);
062}