/*
* Copyright (C) The Apache Software Foundation. All rights reserved.
*
* This software is published under the terms of the Apache Software
* License version 1.1, a copy of which has been included with this
* distribution in the LICENSE.txt file. */
// Contributors: Mathias Bogaert
package 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="doc-files/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>
<?xml version="1.0" ?>
<!DOCTYPE log4j:eventSet SYSTEM "log4j.dtd" [<!ENTITY data SYSTEM "abc">]>
<log4j:eventSet version="1.2" xmlns:log4j="http://jakarta.apache.org/log4j/">
&data;
</log4j:eventSet>
</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 Gülcü
* @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 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(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;
}
}
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