/webportal/src/main/java/org/apache/log4j/filter/MDCMatchFilter.java

  1/*
  2 * Copyright 1999,2004 The Apache Software Foundation.
  3 *
  4 * Licensed under the Apache License, Version 2.0 (the "License");
  5 * you may not use this file except in compliance with the License.
  6 * You may obtain a copy of the License at
  7 *
  8 *      http://www.apache.org/licenses/LICENSE-2.0
  9 *
 10 * Unless required by applicable law or agreed to in writing, software
 11 * distributed under the License is distributed on an "AS IS" BASIS,
 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 13 * See the License for the specific language governing permissions and
 14 * limitations under the License.
 15 */
 16
 17package org.apache.log4j.filter;
 18
 19import org.apache.log4j.spi.LoggingEvent;
 20import org.apache.log4j.MDC;
 21
 22
 23/**
 24  The MDCMatchFilter matches a configured value against the
 25  value of a configured key in the MDC of a logging event.
 26
 27  <p>The filter admits three options <b>KeyToMatch</b>,
 28  <b>ValueToMatch</b>, and <b>ExactMatch</b>.
 29
 30  <p>The value of <b>KeyToMatch</b> property determines which
 31  key is used to match against in the MDC. The value of that
 32  key is used to test against the <b>ValueToMatch</b property.
 33  The <b>KeyToMatch</b> property must be set before this filter
 34  can function properly.
 35
 36  <p>The value of <b>ValueToMatch</b> property determines the
 37  string value to match against. If <b>ExactMatch</b> is set
 38  to true, a match will occur only when <b>ValueToMatch</b> exactly
 39  matches the MDC value of the logging event.  Otherwise, if the
 40  <b>ExactMatch</b> property is set to <code>false</code>, a match
 41  will occur if <b>ValueToMatch</b> is contained anywhere within the
 42  MDC value. The <b>ExactMatch</b> property is set to
 43  <code>false</code> by default.
 44
 45  <p>Note that by default the value to match is set to
 46  <code>null</code> and will only match if the key is not contained
 47  or the value is null in the MDC.
 48
 49  <p>For more information about how the logging event will be
 50  passed to the appender for reporting, please see
 51  the {@link MatchFilterBase} class.
 52
 53  @author Mark Womack
 54
 55  @since 1.3
 56*/
 57public class MDCMatchFilter extends MatchFilterBase {
 58  /**
 59    The key to match in the MDC of the LoggingEvent. */
 60  String keyToMatch;
 61
 62  /**
 63    The value to match in the MDC value of the LoggingEvent. */
 64  String valueToMatch;
 65
 66  /**
 67    Do we look for an exact match or just a "contains" match? */
 68  boolean exactMatch = false;
 69
 70  /**
 71    Sets the key to match in the MDC of the LoggingEvent.
 72
 73    @param key The key that will be matched. */
 74  public void setKeyToMatch(String key) {
 75    keyToMatch = key;
 76  }
 77
 78  /**
 79    Gets the key to match in the MDC of the LoggingEvent.
 80
 81    @return String The key that will be matched. */
 82  public String getKeyToMatch() {
 83    return keyToMatch;
 84  }
 85
 86  /**
 87    Sets the value to match in the NDC value of the LoggingEvent.
 88
 89    @param value The value to match. */
 90  public void setValueToMatch(String value) {
 91    valueToMatch = value;
 92  }
 93
 94  /**
 95    Gets the value to match in the NDC value of the LoggingEvent.
 96
 97    @return String The value to match. */
 98  public String getValueToMatch() {
 99    return valueToMatch;
100  }
101
102  /**
103    Set to true if configured value must exactly match the MDC
104    value of the LoggingEvent. Set to false if the configured
105    value must only be contained in the MDC value of the
106    LoggingEvent. Default is false.
107
108    @param exact True if an exact match should be checked for. */
109  public void setExactMatch(boolean exact) {
110    exactMatch = exact;
111  }
112
113  /**
114    Returns the true if an exact match will be checked for.
115
116    @return boolean True if an exact match will be checked for. */
117  public boolean getExactMatch() {
118    return exactMatch;
119  }
120
121  /**
122    Returns true if a key to match has been configured.
123
124    @return boolean True if a match can be performed. */
125  protected boolean canMatch() {
126    return (keyToMatch != null);
127  }
128
129  /**
130    If <b>ExactMatch</b> is set to true, returns true only when
131    <b>ValueToMatch</b> exactly matches the MDC value of the
132    logging event. If the <b>ExactMatch</b> property
133    is set to <code>false</code>, returns true when
134    <b>ValueToMatch</b> is contained anywhere within the MDC
135    value. Otherwise, false is returned.
136
137    @param event The logging event to match against.
138    @return boolean True if matches criteria. */
139  protected boolean match(LoggingEvent event) {
140    // get the mdc value for the key from the event
141    // use the toString() value of the value object
142    //Object mdcObject = event.getMDC(keyToMatch); //removed in Log4j-1.3
143    Object mdcObject = MDC.get(keyToMatch);
144    String mdcValue;
145
146    if (mdcObject != null) {
147      mdcValue = mdcObject.toString();
148    } else {
149      mdcValue = null;
150    }
151
152    // check for a match
153    if (mdcValue == null) {
154      return (valueToMatch == null);
155    } else {
156      if (valueToMatch != null) {
157        if (exactMatch) {
158          return mdcValue.equals(valueToMatch);
159        } else {
160          return (mdcValue.indexOf(valueToMatch) != -1);
161        }
162      } else {
163        return false;
164      }
165    }
166  }
167}