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 */
017
018package org.apache.logging.log4j.core;
019
020import org.apache.logging.log4j.Level;
021import org.apache.logging.log4j.Marker;
022import org.apache.logging.log4j.message.Message;
023import org.apache.logging.log4j.util.EnglishEnums;
024
025/**
026 * Interface that must be implemented to allow custom event filtering. It is highly recommended that
027 * applications make use of the Filters provided with this implementation before creating their own.
028 *
029 * <p>This interface supports "global" filters (i.e. - all events must pass through them first), attached to
030 * specific loggers and associated with Appenders. It is recommended that, where possible, Filter implementations
031 * create a generic filtering method that can be called from any of the filter methods.</p>
032 */
033public interface Filter extends LifeCycle {
034
035    /**
036     * Main {@linkplain org.apache.logging.log4j.core.config.plugins.Plugin#elementType() plugin element type} for
037     * Filter plugins.
038     *
039     * @since 2.1
040     */
041    String ELEMENT_TYPE = "filter";
042
043    /**
044     * The result that can returned from a filter method call.
045     */
046     enum Result {
047        /**
048         * The event will be processed without further filtering based on the log Level.
049         */
050        ACCEPT,
051        /**
052         * No decision could be made, further filtering should occur.
053         */
054        NEUTRAL,
055        /**
056         * The event should not be processed.
057         */
058        DENY;
059
060        /**
061         * Returns the Result for the given string.
062         *
063         * @param name The Result enum name, case-insensitive. If null, returns, null
064         * @return a Result enum value or null if name is null
065         */
066        public static Result toResult(final String name) {
067            return toResult(name, null);
068        }
069
070        /**
071         * Returns the Result for the given string.
072         *
073         * @param name The Result enum name, case-insensitive. If null, returns, defaultResult
074         * @param defaultResult the Result to return if name is null
075         * @return a Result enum value or null if name is null
076         */
077        public static Result toResult(final String name, final Result defaultResult) {
078            return EnglishEnums.valueOf(Result.class, name, defaultResult);
079        }
080}
081
082    /**
083     * Returns the result that should be returned when the filter does not match the event.
084     * @return the Result that should be returned when the filter does not match the event.
085     */
086    Result getOnMismatch();
087    /**
088     * Returns the result that should be returned when the filter matches the event.
089     * @return the Result that should be returned when the filter matches the event.
090     */
091    Result getOnMatch();
092
093    /**
094     * Filter an event.
095     * @param logger The Logger.
096     * @param level The event logging Level.
097     * @param marker The Marker for the event or null.
098     * @param msg String text to filter on.
099     * @param params An array of parameters or null.
100     * @return the Result.
101     */
102    Result filter(Logger logger, Level level, Marker marker, String msg, Object... params);
103
104    /**
105     * Filter an event.
106     *
107     * @param logger The Logger.
108     * @param level the event logging level.
109     * @param marker The Marker for the event or null.
110     * @param message The message.
111     * @param p0 the message parameters
112     * @return the Result.
113     */
114    Result filter(Logger logger, Level level, Marker marker, String message, Object p0);
115
116    /**
117     * Filter an event.
118     *
119     * @param logger The Logger.
120     * @param level the event logging level.
121     * @param marker The Marker for the event or null.
122     * @param message The message.
123     * @param p0 the message parameters
124     * @param p1 the message parameters
125     * @return the Result.
126     */
127    Result filter(Logger logger, Level level, Marker marker, String message, Object p0, Object p1);
128
129    /**
130     * Filter an event.
131     *
132     * @param logger The Logger.
133     * @param level the event logging level.
134     * @param marker The Marker for the event or null.
135     * @param message The message.
136     * @param p0 the message parameters
137     * @param p1 the message parameters
138     * @param p2 the message parameters
139     * @return the Result.
140     */
141    Result filter(Logger logger, Level level, Marker marker, String message, Object p0, Object p1, Object p2);
142
143    /**
144     * Filter an event.
145     *
146     * @param logger The Logger.
147     * @param level the event logging level.
148     * @param marker The Marker for the event or null.
149     * @param message The message.
150     * @param p0 the message parameters
151     * @param p1 the message parameters
152     * @param p2 the message parameters
153     * @param p3 the message parameters
154     * @return the Result.
155     */
156    Result filter(Logger logger, Level level, Marker marker, String message, Object p0, Object p1, Object p2, Object p3);
157
158    /**
159     * Filter an event.
160     *
161     * @param logger The Logger.
162     * @param level the event logging level.
163     * @param marker The Marker for the event or null.
164     * @param message The message.
165     * @param p0 the message parameters
166     * @param p1 the message parameters
167     * @param p2 the message parameters
168     * @param p3 the message parameters
169     * @param p4 the message parameters
170     * @return the Result.
171     */
172    Result filter(Logger logger, Level level, Marker marker, String message, Object p0, Object p1, Object p2, Object p3,
173            Object p4);
174
175    /**
176     * Filter an event.
177     *
178     * @param logger The Logger.
179     * @param level the event logging level.
180     * @param marker The Marker for the event or null.
181     * @param message The message.
182     * @param p0 the message parameters
183     * @param p1 the message parameters
184     * @param p2 the message parameters
185     * @param p3 the message parameters
186     * @param p4 the message parameters
187     * @param p5 the message parameters
188     * @return the Result.
189     */
190    Result filter(Logger logger, Level level, Marker marker, String message, Object p0, Object p1, Object p2, Object p3,
191            Object p4, Object p5);
192
193    /**
194     * Filter an event.
195     *
196     * @param logger The Logger.
197     * @param level the event logging level.
198     * @param marker The Marker for the event or null.
199     * @param message The message.
200     * @param p0 the message parameters
201     * @param p1 the message parameters
202     * @param p2 the message parameters
203     * @param p3 the message parameters
204     * @param p4 the message parameters
205     * @param p5 the message parameters
206     * @param p6 the message parameters
207     * @return the Result.
208     */
209    Result filter(Logger logger, Level level, Marker marker, String message, Object p0, Object p1, Object p2, Object p3,
210            Object p4, Object p5, Object p6);
211
212    /**
213     * Filter an event.
214     *
215     * @param logger The Logger.
216     * @param level the event logging level.
217     * @param marker The Marker for the event or null.
218     * @param message The message.
219     * @param p0 the message parameters
220     * @param p1 the message parameters
221     * @param p2 the message parameters
222     * @param p3 the message parameters
223     * @param p4 the message parameters
224     * @param p5 the message parameters
225     * @param p6 the message parameters
226     * @param p7 the message parameters
227     * @return the Result.
228     */
229    Result filter(Logger logger, Level level, Marker marker, String message, Object p0, Object p1, Object p2, Object p3,
230            Object p4, Object p5, Object p6, Object p7);
231
232    /**
233     * Filter an event.
234     *
235     * @param logger The Logger.
236     * @param level the event logging level.
237     * @param marker The Marker for the event or null.
238     * @param message The message.
239     * @param p0 the message parameters
240     * @param p1 the message parameters
241     * @param p2 the message parameters
242     * @param p3 the message parameters
243     * @param p4 the message parameters
244     * @param p5 the message parameters
245     * @param p6 the message parameters
246     * @param p7 the message parameters
247     * @param p8 the message parameters
248     * @return the Result.
249     */
250    Result filter(Logger logger, Level level, Marker marker, String message, Object p0, Object p1, Object p2, Object p3,
251            Object p4, Object p5, Object p6, Object p7, Object p8);
252
253    /**
254     * Filter an event.
255     *
256     * @param logger The Logger.
257     * @param level the event logging level.
258     * @param marker The Marker for the event or null.
259     * @param message The message.
260     * @param p0 the message parameters
261     * @param p1 the message parameters
262     * @param p2 the message parameters
263     * @param p3 the message parameters
264     * @param p4 the message parameters
265     * @param p5 the message parameters
266     * @param p6 the message parameters
267     * @param p7 the message parameters
268     * @param p8 the message parameters
269     * @param p9 the message parameters
270     * @return the Result.
271     */
272    Result filter(Logger logger, Level level, Marker marker, String message, Object p0, Object p1, Object p2, Object p3,
273            Object p4, Object p5, Object p6, Object p7, Object p8, Object p9);
274
275    /**
276     * Filter an event.
277     * @param logger The Logger.
278     * @param level The event logging Level.
279     * @param marker The Marker for the event or null.
280     * @param msg Any Object.
281     * @param t A Throwable or null.
282     * @return the Result.
283     */
284    Result filter(Logger logger, Level level, Marker marker, Object msg, Throwable t);
285
286    /**
287     * Filter an event.
288     * @param logger The Logger.
289     * @param level The event logging Level.
290     * @param marker The Marker for the event or null.
291     * @param msg The Message
292     * @param t A Throwable or null.
293     * @return the Result.
294     */
295    Result filter(Logger logger, Level level, Marker marker, Message msg, Throwable t);
296
297    /**
298     * Filter an event.
299     * @param event The Event to filter on.
300     * @return the Result.
301     */
302    Result filter(LogEvent event);
303
304}