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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  // Please note that if you move this class, make sure to update the Interpolator class (if still applicable) or remove
19  // this comment if no longer relevant
20  
21  import javax.servlet.ServletContext;
22  
23  import org.apache.logging.log4j.core.LogEvent;
24  import org.apache.logging.log4j.core.config.plugins.Plugin;
25  import org.apache.logging.log4j.core.lookup.AbstractLookup;
26  
27  @Plugin(name = "web", category = "Lookup")
28  public class WebLookup extends AbstractLookup {
29      private static final String ATTR_PREFIX = "attr.";
30      private static final String INIT_PARAM_PREFIX = "initParam.";
31  
32      /**
33       * @deprecated Use {@link WebLoggerContextUtils#getServletContext()}.
34       */
35      @Deprecated
36      protected ServletContext getServletContext() {
37          return WebLoggerContextUtils.getServletContext();
38      }
39  
40      @Override
41      public String lookup(final LogEvent event, final String key) {
42          final ServletContext ctx = WebLoggerContextUtils.getServletContext();
43          if (ctx == null) {
44              return null;
45          }
46  
47          if (key.startsWith(ATTR_PREFIX)) {
48              final String attrName = key.substring(ATTR_PREFIX.length());
49              final Object attrValue = ctx.getAttribute(attrName);
50              return attrValue == null ? null : attrValue.toString();
51          }
52  
53          if (key.startsWith(INIT_PARAM_PREFIX)) {
54              final String paramName = key.substring(INIT_PARAM_PREFIX.length());
55              return ctx.getInitParameter(paramName);
56          }
57  
58          if ("rootDir".equals(key)) {
59              final String root = ctx.getRealPath("/");
60              if (root == null) {
61                  final String msg = "Failed to resolve web:rootDir -- " +
62                          "servlet container unable to translate virtual path " +
63                          " to real path (probably not deployed as exploded";
64                  throw new IllegalStateException(msg);
65              }
66              return root;
67          }
68  
69          if ("contextPath".equals(key)) {
70              return ctx.getContextPath();
71          }
72  
73          if ("servletContextName".equals(key)) {
74              return ctx.getServletContextName();
75          }
76  
77          if ("serverInfo".equals(key)) {
78              return ctx.getServerInfo();
79          }
80  
81          if ("effectiveMajorVersion".equals(key)) {
82              return String.valueOf(ctx.getEffectiveMajorVersion());
83          }
84  
85          if ("effectiveMinorVersion".equals(key)) {
86              return String.valueOf(ctx.getEffectiveMinorVersion());
87          }
88  
89          if ("majorVersion".equals(key)) {
90              return String.valueOf(ctx.getMajorVersion());
91          }
92  
93          if ("minorVersion".equals(key)) {
94              return String.valueOf(ctx.getMinorVersion());
95          }
96  
97          if (ctx.getAttribute(key) != null) {
98              return ctx.getAttribute(key).toString();
99          }
100 
101         if (ctx.getInitParameter(key) != null) {
102             return ctx.getInitParameter(key);
103         }
104 
105         ctx.log(getClass().getName() + " unable to resolve key '" + key + '\'');
106         return null;
107     }
108 }