1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache license, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the license for the specific language governing permissions and
15 * limitations under the license.
16 */
17
18 package org.apache.logging.log4j.core;
19
20 import java.util.Locale;
21
22 import org.apache.logging.log4j.Level;
23 import org.apache.logging.log4j.Marker;
24 import org.apache.logging.log4j.core.net.Protocol;
25 import org.apache.logging.log4j.message.Message;
26 import org.apache.logging.log4j.util.EnglishEnums;
27
28 /**
29 * Interface that must be implemented to allow custom event filtering. It is highly recommended that
30 * applications make use of the Filters provided with this implementation before creating their own.
31 *
32 * This interface supports "global" filters (i.e. - all events must pass through them first), attached to
33 * specific loggers and associated with Appenders. It is recommended that, where possible, Filter implementations
34 * create a generic filtering method that can be called from any of the filter methods.
35 */
36 public interface Filter {
37
38 /**
39 * The result that can returned from a filter method call.
40 */
41 public enum Result {
42 /**
43 * The event will be processed without further filtering based on the log Level.
44 */
45 ACCEPT,
46 /**
47 * No decision could be made, further filtering should occur.
48 */
49 NEUTRAL,
50 /**
51 * The event should not be processed.
52 */
53 DENY;
54
55 /**
56 * Returns the Result for the given string.
57 *
58 * @param name The Result enum name, case-insensitive. If null, returns, null
59 * @return a Result enum value or null if name is null
60 */
61 public static Result toResult(String name) {
62 return toResult(name, null);
63 }
64
65 /**
66 * Returns the Result for the given string.
67 *
68 * @param name The Result enum name, case-insensitive. If null, returns, defaultResult
69 * @param defaultResult the Result to return if name is null
70 * @return a Result enum value or null if name is null
71 */
72 public static Result toResult(String name, Result defaultResult) {
73 return EnglishEnums.valueOf(Result.class, name, defaultResult);
74 }
75 }
76
77 /**
78 * Returns the result that should be returned when the filter does not match the event.
79 * @return the Result that should be returned when the filter does not match the event.
80 */
81 Result getOnMismatch();
82 /**
83 * Returns the result that should be returned when the filter matches the event.
84 * @return the Result that should be returned when the filter matches the event.
85 */
86 Result getOnMatch();
87
88 /**
89 * Filter an event.
90 * @param logger The Logger.
91 * @param level The event logging Level.
92 * @param marker The Marker for the event or null.
93 * @param msg String text to filter on.
94 * @param params An array of parameters or null.
95 * @return the Result.
96 */
97 Result filter(Logger logger, Level level, Marker marker, String msg, Object... params);
98
99 /**
100 * Filter an event.
101 * @param logger The Logger.
102 * @param level The event logging Level.
103 * @param marker The Marker for the event or null.
104 * @param msg Any Object.
105 * @param t A Throwable or null.
106 * @return the Result.
107 */
108 Result filter(Logger logger, Level level, Marker marker, Object msg, Throwable t);
109
110 /**
111 * Filter an event.
112 * @param logger The Logger.
113 * @param level The event logging Level.
114 * @param marker The Marker for the event or null.
115 * @param msg The Message
116 * @param t A Throwable or null.
117 * @return the Result.
118 */
119 Result filter(Logger logger, Level level, Marker marker, Message msg, Throwable t);
120
121 /**
122 * Filter an event.
123 * @param event The Event to filter on.
124 * @return the Result.
125 */
126 Result filter(LogEvent event);
127
128 }