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1   /*
2    *  Licensed to the Apache Software Foundation (ASF) under one
3    *  or more contributor license agreements.  See the NOTICE file
4    *  distributed with this work for additional information
5    *  regarding copyright ownership.  The ASF licenses this file
6    *  to you under the Apache License, Version 2.0 (the
7    *  "License"); you may not use this file except in compliance
8    *  with the License.  You may obtain a copy of the License at
9    *
10   *    http://www.apache.org/licenses/LICENSE-2.0
11   *
12   *  Unless required by applicable law or agreed to in writing,
13   *  software distributed under the License is distributed on an
14   *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15   *  KIND, either express or implied.  See the License for the
16   *  specific language governing permissions and limitations
17   *  under the License.
18   *
19   */
20  package org.apache.mina.util;
21  
22  import java.util.Arrays;
23  import java.util.Map;
24  import java.util.Set;
25  import java.util.logging.Formatter;
26  import java.util.logging.LogRecord;
27  
28  import org.slf4j.MDC;
29  
30  /**
31   * Implementation of {@link java.util.logging.Formatter} that generates xml in the log4j format.
32   * <p>
33   * The generated xml corresponds 100% with what is generated by
34   * log4j's <a href=http://logging.apache.org/log4j/1.2/apidocs/org/apache/log4j/xml/XMLLayout.html">XMLLayout</a>
35   * <p>
36   * The MDC properties will only be correct when <code>format</code> is called from the same thread
37   * that generated the LogRecord.
38   * <p>
39   * The file and line attributes in the locationInfo element will always be "?"
40   * since java.util.logging.LogRecord does not provide that info.
41   * <p>
42   * The implementation is heavily based on org.apache.log4j.xml.XMLLayout
43   * </p>
44   *
45   * @author <a href="http://mina.apache.org">Apache MINA Project</a>
46   */
47  public class Log4jXmlFormatter extends Formatter {
48  
49      private final int DEFAULT_SIZE = 256;
50  
51      private final int UPPER_LIMIT = 2048;
52  
53      private StringBuffer buf = new StringBuffer(DEFAULT_SIZE);
54  
55      private boolean locationInfo = false;
56  
57      private boolean properties = false;
58  
59      /**
60       * The <b>LocationInfo</b> option takes a boolean value. By default,
61       * it is set to false which means there will be no location
62       * information output by this layout. If the the option is set to
63       * true, then the file name and line number of the statement at the
64       * origin of the log statement will be output.
65       *
66       * @param flag whether locationInfo should be output by this layout
67       */
68      public void setLocationInfo(boolean flag) {
69          locationInfo = flag;
70      }
71  
72      /**
73       * Returns the current value of the <b>LocationInfo</b> option.
74       *
75       * @return whether locationInfo will be output by this layout
76       */
77      public boolean getLocationInfo() {
78          return locationInfo;
79      }
80  
81      /**
82       * Sets whether MDC key-value pairs should be output, default false.
83       *
84       * @param flag new value.
85       */
86      public void setProperties(final boolean flag) {
87          properties = flag;
88      }
89  
90      /**
91       * Gets whether MDC key-value pairs should be output.
92       *
93       * @return true if MDC key-value pairs are output.
94       */
95      public boolean getProperties() {
96          return properties;
97      }
98  
99      @Override
100     @SuppressWarnings("unchecked")
101     public String format(final LogRecord record) {
102         // Reset working buffer. If the buffer is too large, then we need a new
103         // one in order to avoid the penalty of creating a large array.
104         if (buf.capacity() > UPPER_LIMIT) {
105             buf = new StringBuffer(DEFAULT_SIZE);
106         } else {
107             buf.setLength(0);
108         }
109         buf.append("<log4j:event logger=\"");
110         buf.append(Transform.escapeTags(record.getLoggerName()));
111         buf.append("\" timestamp=\"");
112         buf.append(record.getMillis());
113         buf.append("\" level=\"");
114 
115         buf.append(Transform.escapeTags(record.getLevel().getName()));
116         buf.append("\" thread=\"");
117         buf.append(String.valueOf(record.getThreadID()));
118         buf.append("\">\r\n");
119 
120         buf.append("<log4j:message><![CDATA[");
121         // Append the rendered message. Also make sure to escape any
122         // existing CDATA sections.
123         Transform.appendEscapingCDATA(buf, record.getMessage());
124         buf.append("]]></log4j:message>\r\n");
125 
126         if (record.getThrown() != null) {
127             String[] s = Transform.getThrowableStrRep(record.getThrown());
128             if (s != null) {
129                 buf.append("<log4j:throwable><![CDATA[");
130                 for (String value : s) {
131                     Transform.appendEscapingCDATA(buf, value);
132                     buf.append("\r\n");
133                 }
134                 buf.append("]]></log4j:throwable>\r\n");
135             }
136         }
137 
138         if (locationInfo) {
139             buf.append("<log4j:locationInfo class=\"");
140             buf.append(Transform.escapeTags(record.getSourceClassName()));
141             buf.append("\" method=\"");
142             buf.append(Transform.escapeTags(record.getSourceMethodName()));
143             buf.append("\" file=\"?\" line=\"?\"/>\r\n");
144         }
145 
146         if (properties) {
147             Map contextMap = MDC.getCopyOfContextMap();
148             if (contextMap != null) {
149                 Set keySet = contextMap.keySet();
150                 if ((keySet != null) && (keySet.size() > 0)) {
151                     buf.append("<log4j:properties>\r\n");
152                     Object[] keys = keySet.toArray();
153                     Arrays.sort(keys);
154                     for (Object key1 : keys) {
155                         String key = (key1 == null ? "" : key1.toString());
156                         Object val = contextMap.get(key);
157                         if (val != null) {
158                             buf.append("<log4j:data name=\"");
159                             buf.append(Transform.escapeTags(key));
160                             buf.append("\" value=\"");
161                             buf.append(Transform.escapeTags(String.valueOf(val)));
162                             buf.append("\"/>\r\n");
163                         }
164                     }
165                     buf.append("</log4j:properties>\r\n");
166                 }
167             }
168 
169         }
170         buf.append("</log4j:event>\r\n\r\n");
171 
172         return buf.toString();
173     }
174 
175 }