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 package org.apache.logging.log4j.web;
18
19 import org.apache.logging.log4j.spi.LoggerContext;
20
21 /**
22 * Specifies an interface for setting and clearing a thread-bound {@link LoggerContext} in a Java EE web application.
23 * Also defines constants for context parameter and attribute names. In most cases you will never need to use this
24 * directly because the Log4j filter handles this task automatically. However, in async operations you should wrap
25 * code that executes in separate threads with {@link #setLoggerContext} and {@link #clearLoggerContext}.
26 *
27 * <p>
28 * You can obtain the instance of this for your web application by retrieving the {@link javax.servlet.ServletContext}
29 * attribute named {@code org.apache.logging.log4j.core.web.Log4jWebSupport.INSTANCE}. If needed, you can also obtain
30 * the {@link LoggerContext} instance for your web application by retrieving the {@code ServletContext} attribute named
31 * {@code org.apache.logging.log4j.spi.LoggerContext.INSTANCE}.
32 * </p>
33 */
34 public interface Log4jWebSupport {
35 /**
36 * The {@link javax.servlet.ServletContext} parameter name for the name of the
37 * {@link org.apache.logging.log4j.core.LoggerContext}.
38 */
39 String LOG4J_CONTEXT_NAME = "log4jContextName";
40
41 /**
42 * The {@link javax.servlet.ServletContext} parameter name for the location of the configuration.
43 */
44 String LOG4J_CONFIG_LOCATION = "log4jConfiguration";
45
46 /**
47 * The {@link javax.servlet.ServletContext} parameter name for the JNDI flag.
48 */
49 String IS_LOG4J_CONTEXT_SELECTOR_NAMED = "isLog4jContextSelectorNamed";
50
51 /**
52 * The {@link javax.servlet.ServletContext} parameter name for the flag that disables Log4j's auto-initialization
53 * in Servlet 3.0+ web applications. Set a context parameter with this name to "true" to disable
54 * auto-initialization.
55 */
56 String IS_LOG4J_AUTO_INITIALIZATION_DISABLED = "isLog4jAutoInitializationDisabled";
57
58 /**
59 * The attribute key for the {@link javax.servlet.ServletContext} attribute that the singleton support instance
60 * is stored in.
61 */
62 String SUPPORT_ATTRIBUTE = Log4jWebSupport.class.getName() + ".INSTANCE";
63
64 /**
65 * The attribute key for the {@link javax.servlet.ServletContext} attribute that the {@link LoggerContext}
66 * is stored in.
67 */
68 String CONTEXT_ATTRIBUTE = LoggerContext.class.getName() + ".INSTANCE";
69
70 /**
71 * Sets the logger context so that code executing afterwards can easily and quickly access loggers via
72 * {@link org.apache.logging.log4j.LogManager#getLogger}.
73 */
74 void setLoggerContext();
75
76 /**
77 * Clears the logger context set up in {@link #setLoggerContext}.
78 */
79 void clearLoggerContext();
80
81 /**
82 * Sets the logger context by calling {@link #setLoggerContext}, executes the runnable argument, then clears the
83 * logger context by calling {@link #clearLoggerContext}.
84 *
85 * @param runnable The runnable to execute wrapped with a configured logger context
86 */
87 void wrapExecution(Runnable runnable);
88 }