XMLFileHandler xref

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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.log4j.chainsaw;
    18
    19  import java.util.StringTokenizer;
    20  import org.apache.log4j.Level;
    21  import org.xml.sax.Attributes;
    22  import org.xml.sax.SAXException;
    23  import org.xml.sax.helpers.DefaultHandler;
    24
    25  /**
    26   * A content handler for document containing Log4J events logged using the
    27   * XMLLayout class. It will create events and add them to a supplied model.
    28   *
    29   * @author <a href="mailto:oliver@puppycrawl.com">Oliver Burn</a>
    30   * @version 1.0
    31   */
    32  class XMLFileHandler
    33      extends DefaultHandler
    34  {
    35      /** represents the event tag **/
    36      private static final String TAG_EVENT = "log4j:event";
    37      /** represents the message tag **/
    38      private static final String TAG_MESSAGE = "log4j:message";
    39      /** represents the ndc tag **/
    40      private static final String TAG_NDC = "log4j:NDC";
    41      /** represents the throwable tag **/
    42      private static final String TAG_THROWABLE = "log4j:throwable";
    43      /** represents the location info tag **/
    44      private static final String TAG_LOCATION_INFO = "log4j:locationInfo";
    45
    46      /** where to put the events **/
    47      private final MyTableModel mModel;
    48      /** the number of events in the document **/
    49      private int mNumEvents;
    50
    51      /** the time of the event **/
    52      private long mTimeStamp;
    53      /** the priority (level) of the event **/
    54      private Level mLevel;
    55      /** the category of the event **/
    56      private String mCategoryName;
    57      /** the NDC for the event **/
    58      private String mNDC;
    59      /** the thread for the event **/
    60      private String mThreadName;
    61      /** the msg for the event **/
    62      private String mMessage;
    63      /** the throwable details the event **/
    64      private String[] mThrowableStrRep;
    65      /** the location details for the event **/
    66      private String mLocationDetails;
    67      /** buffer for collecting text **/
    68      private final StringBuffer mBuf = new StringBuffer();
    69
    70      /**
    71       * Creates a new <code>XMLFileHandler</code> instance.
    72       *
    73       * @param aModel where to add the events
    74       */
    75      XMLFileHandler(MyTableModel aModel) {
    76          mModel = aModel;
    77      }
    78
    79      /** @see DefaultHandler **/
    80      public void startDocument()
    81          throws SAXException
    82      {
    83          mNumEvents = 0;
    84      }
    85
    86      /** @see DefaultHandler **/
    87      public void characters(char[] aChars, int aStart, int aLength) {
    88          mBuf.append(String.valueOf(aChars, aStart, aLength));
    89      }
    90
    91      /** @see DefaultHandler **/
    92      public void endElement(String aNamespaceURI,
    93                             String aLocalName,
    94                             String aQName)
    95      {
    96          if (TAG_EVENT.equals(aQName)) {
    97              addEvent();
    98              resetData();
    99          } else if (TAG_NDC.equals(aQName)) {
    100             mNDC = mBuf.toString();
    101         } else if (TAG_MESSAGE.equals(aQName)) {
    102             mMessage = mBuf.toString();
    103         } else if (TAG_THROWABLE.equals(aQName)) {
    104             final StringTokenizer st =
    105                 new StringTokenizer(mBuf.toString(), "\n\t");
    106             mThrowableStrRep = new String[st.countTokens()];
    107             if (mThrowableStrRep.length > 0) {
    108                 mThrowableStrRep[0] = st.nextToken();
    109                 for (int i = 1; i < mThrowableStrRep.length; i++) {
    110                     mThrowableStrRep[i] = "\t" + st.nextToken();
    111                 }
    112             }
    113         }
    114     }
    115
    116     /** @see DefaultHandler **/
    117     public void startElement(String aNamespaceURI,
    118                              String aLocalName,
    119                              String aQName,
    120                              Attributes aAtts)
    121     {
    122         mBuf.setLength(0);
    123
    124         if (TAG_EVENT.equals(aQName)) {
    125             mThreadName = aAtts.getValue("thread");
    126             mTimeStamp = Long.parseLong(aAtts.getValue("timestamp"));
    127             mCategoryName = aAtts.getValue("logger");
    128             mLevel = Level.toLevel(aAtts.getValue("level"));
    129         } else if (TAG_LOCATION_INFO.equals(aQName)) {
    130             mLocationDetails = aAtts.getValue("class") + "."
    131                 + aAtts.getValue("method")
    132                 + "(" + aAtts.getValue("file") + ":" + aAtts.getValue("line")
    133                 + ")";
    134         }
    135     }
    136
    137     /** @return the number of events in the document **/
    138     int getNumEvents() {
    139         return mNumEvents;
    140     }
    141
    142     ////////////////////////////////////////////////////////////////////////////
    143     // Private methods
    144     ////////////////////////////////////////////////////////////////////////////
    145
    146     /** Add an event to the model **/
    147     private void addEvent() {
    148         mModel.addEvent(new EventDetails(mTimeStamp,
    149                                          mLevel,
    150                                          mCategoryName,
    151                                          mNDC,
    152                                          mThreadName,
    153                                          mMessage,
    154                                          mThrowableStrRep,
    155                                          mLocationDetails));
    156         mNumEvents++;
    157     }
    158
    159     /** Reset the data for an event **/
    160     private void resetData() {
    161         mTimeStamp = 0;
    162         mLevel = null;
    163         mCategoryName = null;
    164         mNDC = null;
    165         mThreadName = null;
    166         mMessage = null;
    167         mThrowableStrRep = null;
    168         mLocationDetails = null;
    169     }
    170 }