/* * Copyright 1999-2005 The Apache Software Foundation. *  * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at *  *      http://www.apache.org/licenses/LICENSE-2.0 *  * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */// Contributors:   Mathias Bogaertpackage org.apache.log4j.xml;import org.apache.log4j.Layout;import org.apache.log4j.spi.LoggingEvent;import org.apache.log4j.spi.LocationInfo;import org.apache.log4j.helpers.OptionConverter;import org.apache.log4j.helpers.DateLayout;import org.apache.log4j.helpers.Transform;/** * The output of the XMLLayout consists of a series of log4j:event * elements as defined in the <a * href="log4j.dtd">log4j.dtd</a>. It does not output a * complete well-formed XML file. The output is designed to be * included as an <em>external entity</em> in a separate file to form * a correct XML file. * * <p>For example, if <code>abc</code> is the name of the file where * the XMLLayout ouput goes, then a well-formed XML file would be: *  <pre>   &lt;?xml version="1.0" ?&gt;   &lt;!DOCTYPE log4j:eventSet SYSTEM "log4j.dtd" [&lt;!ENTITY data SYSTEM "abc"&gt;]&gt;   &lt;log4j:eventSet version="1.2" xmlns:log4j="http://jakarta.apache.org/log4j/"&gt; 	&nbsp;&nbsp;&data;  &lt;/log4j:eventSet&gt;  </pre>  * <p>This approach enforces the independence of the XMLLayout and the * appender where it is embedded. * * <p>The <code>version</code> attribute helps components to correctly * intrepret output generated by XMLLayout. The value of this * attribute should be "1.1" for output generated by log4j versions * prior to log4j 1.2 (final release) and "1.2" for relase 1.2 and * later. * * @author Ceki  G&uuml;lc&uuml; * @since 0.9.0  * */public class XMLLayout extends Layout {  private  final int DEFAULT_SIZE = 256;  private final int UPPER_LIMIT = 2048;  private StringBuffer buf = new StringBuffer(DEFAULT_SIZE);  private boolean locationInfo = false;   /**   * The <b>LocationInfo</b> option takes a boolean value. By default,   * it is set to false which means there will be no location   * information output by this layout. If the the option is set to   * true, then the file name and line number of the statement at the   * origin of the log statement will be output.   *   * <p>If you are embedding this layout within an {@link   * org.apache.log4j.net.SMTPAppender} then make sure to set the   * <b>LocationInfo</b> option of that appender as well.   * */  public void setLocationInfo(boolean flag) {    locationInfo = flag;  }    /**     Returns the current value of the <b>LocationInfo</b> option.   */  public boolean getLocationInfo() {    return locationInfo;  }    /** No options to activate. */  public void activateOptions() {  }  /**   * Formats a {@link org.apache.log4j.spi.LoggingEvent} in conformance with the log4j.dtd.   * */  public String format(LoggingEvent event) {    // Reset working buffer. If the buffer is too large, then we need a new    // one in order to avoid the penalty of creating a large array.    if(buf.capacity() > UPPER_LIMIT) {      buf = new StringBuffer(DEFAULT_SIZE);    } else {      buf.setLength(0);    }        // We yield to the \r\n heresy.    buf.append("<log4j:event logger=\"");    buf.append(event.getLoggerName());    buf.append("\" timestamp=\"");    buf.append(event.timeStamp);    buf.append("\" level=\"");    buf.append(event.getLevel());    buf.append("\" thread=\"");    buf.append(event.getThreadName());    buf.append("\">\r\n");    buf.append("<log4j:message><![CDATA[");    // Append the rendered message. Also make sure to escape any    // existing CDATA sections.    Transform.appendEscapingCDATA(buf, event.getRenderedMessage());    buf.append("]]></log4j:message>\r\n");               String ndc = event.getNDC();    if(ndc != null) {      buf.append("<log4j:NDC><![CDATA[");      buf.append(ndc);      buf.append("]]></log4j:NDC>\r\n");           }        String[] s = event.getThrowableStrRep();    if(s != null) {      buf.append("<log4j:throwable><![CDATA[");      for(int i = 0; i < s.length; i++) {	buf.append(s[i]);	buf.append("\r\n");      }      buf.append("]]></log4j:throwable>\r\n");    }        if(locationInfo) {       LocationInfo locationInfo = event.getLocationInformation();	      buf.append("<log4j:locationInfo class=\"");      buf.append(Transform.escapeTags(locationInfo.getClassName()));      buf.append("\" method=\"");      buf.append(Transform.escapeTags(locationInfo.getMethodName()));      buf.append("\" file=\"");      buf.append(locationInfo.getFileName());      buf.append("\" line=\"");      buf.append(locationInfo.getLineNumber());      buf.append("\"/>\r\n");    }        buf.append("</log4j:event>\r\n\r\n");        return buf.toString();  }    /**     The XMLLayout prints and does not ignore exceptions. Hence the     return value <code>false</code>.  */  public boolean ignoresThrowable() {    return false;  }}