Google Git
Sign in
apache / logging-log4j-site / d0d0de55986756593c08e5d2b8059541eacaf428 / . / log4j-2.0-beta8 / manual / eventlogging.html
blob: a08efa5c5597c2280339f1c6df83c99bc312d893 [file] [log] [blame]
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<!--
Licensed to the Apache Software Foundation (ASF) under one or more
contributor license agreements. See the NOTICE file distributed with
this work for additional information regarding copyright ownership.
The ASF licenses this file to You 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.
-->
<!-- Generated by Apache Maven Doxia at Jul 10, 2013 -->
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title>
Log4j 2 API - Apache Log4j 2</title>
<link rel="stylesheet" href="../css/bootstrap.min.css" type="text/css" />
<link rel="stylesheet" href="../css/site.css" type="text/css" />
<script type="text/javascript" src="../js/jquery.min.js"></script>
<script type="text/javascript" src="../js/bootstrap.min.js"></script>
<script type="text/javascript" src="../js/prettify.min.js"></script>
<script type="text/javascript" src="../js/site.js"></script>
<meta name="author" content="Ralph Goers" />
<meta name="Date-Revision-yyyymmdd" content="20130710" />
<meta http-equiv="Content-Language" content="en" />
</head>
<body class="composite">
<img class="logo-left" src="../images/ls-logo.jpg" alt="Apache logging services logo" />
<img class="logo-right" src="../images/logo.jpg" alt="Apache log4j logo" />
<div class="clear"></div>
<div class="navbar">
<div class="navbar-inner">
<div class="container-fluid">
<a class="brand" href="http://logging.apache.org/log4j/2.x/">Apache Log4j 2 &trade;</a>
<ul class="nav">
<li>
<a href="http://wiki.apache.org/logging" class="external" target="_blank" title="Logging Wiki">Logging Wiki</a>
</li>
<li>
<a href="http://www.apache.org/" class="external" target="_blank" title="Apache">Apache</a>
</li>
<li>
<a href="../../../" title="Logging Services">Logging Services</a>
</li>
<li>
<a href="https://analysis.apache.org/dashboard/index/org.apache.logging.log4j:log4j" class="external" target="_blank" title="Sonar">Sonar</a>
</li>
</ul>
</div>
</div>
</div>
<div class="container-fluid">
<table class="layout-table">
<tr>
<td class="sidebar">
<div class="well sidebar-nav">
<ul class="nav nav-list">
<li class="nav-header"><i class="icon-home"></i>Apache Log4j™ 2</li>
<li class="none">
<a href="../index.html" title="About">About</a>
</li>
<li class="none">
<a href="../download.html" title="Download">Download</a>
</li>
<li class="none">
<a href="../maven-artifacts.html" title="Maven and Ivy">Maven and Ivy</a>
</li>
<li class="none">
<a href="../build.html" title="Build">Build</a>
</li>
<li class="none">
<a href="../changelog.html" title="Changelog">Changelog</a>
</li>
</ul>
<ul class="nav nav-list">
<li class="nav-header"><i class="icon-book"></i>Manual</li>
<li class="none">
<a href="../manual/index.html" title="Introduction">Introduction</a>
</li>
<li class="none">
<a href="../manual/architecture.html" title="Architecture">Architecture</a>
</li>
<li class="none">
<a href="../manual/migration.html" title="Log4j 1.x Migration">Log4j 1.x Migration</a>
</li>
<li class="expanded">
<a href="../manual/api.html" title="API">API</a>
<ul>
<li class="none">
<a href="../manual/flowtracing.html" title="Flow Tracing">Flow Tracing</a>
</li>
<li class="none">
<a href="../manual/markers.html" title="Markers">Markers</a>
</li>
<li class="none active">
<a href="../manual/eventlogging.html" title="Event Logging">Event Logging</a>
</li>
<li class="none">
<a href="../manual/messages.html" title="Messages">Messages</a>
</li>
<li class="none">
<a href="../manual/thread-context.html" title="ThreadContext">ThreadContext</a>
</li>
</ul>
</li>
<li class="collapsed">
<a href="../manual/configuration.html" title="Configuration">Configuration</a>
</li>
<li class="collapsed">
<a href="../manual/webapp.html" title="Web Applications">Web Applications</a>
</li>
<li class="collapsed">
<a href="../manual/plugins.html" title="Plugins">Plugins</a>
</li>
<li class="collapsed">
<a href="../manual/lookups.html" title="Lookups">Lookups</a>
</li>
<li class="collapsed">
<a href="../manual/appenders.html" title="Appenders">Appenders</a>
</li>
<li class="collapsed">
<a href="../manual/layouts.html" title="Layouts">Layouts</a>
</li>
<li class="collapsed">
<a href="../manual/filters.html" title="Filters">Filters</a>
</li>
<li class="collapsed">
<a href="../manual/async.html" title="Async Loggers">Async Loggers</a>
</li>
<li class="none">
<a href="../manual/jmx.html" title="JMX">JMX</a>
</li>
<li class="none">
<a href="../manual/logsep.html" title="Logging Separation">Logging Separation</a>
</li>
<li class="collapsed">
<a href="../manual/extending.html" title="Extending Log4j">Extending Log4j</a>
</li>
</ul>
<ul class="nav nav-list">
<li class="nav-header"><i class="icon-cog"></i>Components</li>
<li class="none">
<a href="../log4j-api/index.html" title="API">API</a>
</li>
<li class="none">
<a href="../log4j-core/index.html" title="Implementation">Implementation</a>
</li>
<li class="none">
<a href="../log4j-jcl/index.html" title="Commons Logging Bridge">Commons Logging Bridge</a>
</li>
<li class="none">
<a href="../log4j-1.2-api/index.html" title="Log4j 1.2 API">Log4j 1.2 API</a>
</li>
<li class="none">
<a href="../log4j-slf4j-impl/index.html" title="SLF4J Binding">SLF4J Binding</a>
</li>
<li class="none">
<a href="../log4j-to-slf4j/index.html" title="Log4j 2 to SLF4J Adapter">Log4j 2 to SLF4J Adapter</a>
</li>
<li class="none">
<a href="../log4j-flume-ng/index.html" title="Apache Flume">Apache Flume</a>
</li>
<li class="none">
<a href="../log4j-taglib/index.html" title="Log4j Tag Library">Log4j Tag Library</a>
</li>
<li class="none">
<a href="../log4j-jmx-gui/index.html" title="Log4j JMX GUI">Log4j JMX GUI</a>
</li>
</ul>
<ul class="nav nav-list">
<li class="nav-header"><i class="icon-info-sign"></i>Project Information</li>
<li class="none">
<a href="../dependencies.html" title="Dependencies">Dependencies</a>
</li>
<li class="none">
<a href="../dependency-convergence.html" title="Dependency Convergence">Dependency Convergence</a>
</li>
<li class="none">
<a href="../dependency-management.html" title="Dependency Management">Dependency Management</a>
</li>
<li class="none">
<a href="../team-list.html" title="Project Team">Project Team</a>
</li>
<li class="none">
<a href="../mail-lists.html" title="Mailing Lists">Mailing Lists</a>
</li>
<li class="none">
<a href="../issue-tracking.html" title="Issue Tracking">Issue Tracking</a>
</li>
<li class="none">
<a href="../license.html" title="Project License">Project License</a>
</li>
<li class="none">
<a href="../source-repository.html" title="Source Repository">Source Repository</a>
</li>
<li class="none">
<a href="../project-summary.html" title="Project Summary">Project Summary</a>
</li>
</ul>
<ul class="nav nav-list">
<li class="nav-header"><i class="icon-cog"></i>Project Reports</li>
<li class="none">
<a href="../changes-report.html" title="Changes Report">Changes Report</a>
</li>
<li class="none">
<a href="../jira-report.html" title="JIRA Report">JIRA Report</a>
</li>
<li class="none">
<a href="../surefire-report.html" title="Surefire Report">Surefire Report</a>
</li>
<li class="none">
<a href="../rat-report.html" title="RAT Report">RAT Report</a>
</li>
</ul>
</div>
<div id="poweredBy">
<a href="http://maven.apache.org/" title="Built by Maven" class="poweredBy">
<img class="poweredBy" alt="Built by Maven" src="../images/maven-feather.png" />
</a>
</div>
</td>
<td class="content">
<!-- Licensed to the Apache Software Foundation (ASF) under one or more
contributor license agreements. See the NOTICE file distributed with
this work for additional information regarding copyright ownership.
The ASF licenses this file to You 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. -->
<div class="section"><h2>Log4j 2 API<a name="Log4j_2_API"></a></h2>
<a name="EventLogging"></a>
<div class="section"><h3>Event Logging<a name="Event_Logging"></a></h3>
<p>
The EventLogger class provides a simple mechanism for logging events that occur in an application.
While the EventLogger is useful as a way of initiating events that should be processed by an audit
Logging system, by itself it does not implement any of the features an audit logging system would require
such as guaranteed delivery.
</p>
<p>The recommended way of using the EventLogger in a typical web application is to populate
the ThreadContext Map with data that is related to the entire lifespan of the request such as the user's
id, the user's ip address, the product name, etc. This can easily be done in a servlet filter where
the ThreadContext Map can also be cleared at the end of the request. When an event that needs to be
recorded occurs a StructuredDataMessage should be created and populated.
Then call EventLogger.logEvent(msg) where msg is a reference to the StructuredDataMessage.</p>
<div class="prettyprint linenums"><pre>
import org.apache.logging.log4j.ThreadContext;
import org.apache.commons.lang.time.DateUtils;
import javax.servlet.Filter;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.FilterChain;
import javax.servlet.http.HttpSession;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.TimeZone;
public class RequestFilter implements Filter {
private FilterConfig filterConfig;
private static String TZ_NAME = &quot;timezoneOffset&quot;;
public void init(FilterConfig filterConfig) throws ServletException {
this.filterConfig = filterConfig;
}
/**
* Sample filter that populates the MDC on every request.
*/
public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)
throws IOException, ServletException {
HttpServletRequest request = (HttpServletRequest)servletRequest;
HttpServletResponse response = (HttpServletResponse)servletResponse;
ThreadContext.put(&quot;ipAddress&quot;, request.getRemoteAddr());
HttpSession session = request.getSession(false);
TimeZone timeZone = null;
if (session != null) {
// Something should set this after authentication completes
String loginId = (String)session.getAttribute(&quot;LoginId&quot;);
if (loginId != null) {
ThreadContext.put(&quot;loginId&quot;, loginId);
}
// This assumes there is some javascript on the user's page to create the cookie.
if (session.getAttribute(TZ_NAME) == null) {
if (request.getCookies() != null) {
for (Cookie cookie : request.getCookies()) {
if (TZ_NAME.equals(cookie.getName())) {
int tzOffsetMinutes = Integer.parseInt(cookie.getValue());
timeZone = TimeZone.getTimeZone(&quot;GMT&quot;);
timeZone.setRawOffset((int)(tzOffsetMinutes * DateUtils.MILLIS_PER_MINUTE));
request.getSession().setAttribute(TZ_NAME, tzOffsetMinutes);
cookie.setMaxAge(0);
response.addCookie(cookie);
}
}
}
}
}
ThreadContext.put(&quot;hostname&quot;, servletRequest.getServerName());
ThreadContext.put(&quot;productName&quot;, filterConfig.getInitParameter(&quot;ProductName&quot;));
Threadcontext.put(&quot;locale&quot;, servletRequest.getLocale().getDisplayName());
if (timeZone == null) {
timeZone = TimeZone.getDefault();
}
ThreadContext.put(&quot;timezone&quot;, timeZone.getDisplayName());
filterChain.doFilter(servletRequest, servletResponse);
ThreadContext.clear();
}
public void destroy() {
}
}</pre></div>
<p>Sample class that uses EventLogger.</p>
<div class="prettyprint linenums"><pre>
import org.apache.logging.log4j.StructuredDataMessage;
import org.apache.logging.log4j.EventLogger;
import java.util.Date;
import java.util.UUID;
public class MyApp {
public String doFundsTransfer(Account toAccount, Account fromAccount, long amount) {
toAccount.deposit(amount);
fromAccount.withdraw(amount);
String confirm = UUID.randomUUID().toString();
StructuredDataMessage msg = new StructureDataMessage(confirm, null, &quot;transfer&quot;);
msg.put(&quot;toAccount&quot;, toAccount);
msg.put(&quot;fromAccount&quot;, fromAccount);
msg.put(&quot;amount&quot;, amount);
EventLogger.logEvent(data);
return confirm;
}
}</pre></div>
<p>The EventLogger class uses a Logger named &quot;EventLogger&quot;. EventLogger uses a logging level
of OFF as the default to indicate that it cannot be filtered. These events can be
formatted for printing using the
<a href="../log4j-core/apidocs/org/apache/logging/log4j/core/layout/StructuredDataLayout.html">StructuredDataLayout</a>.
</p>
</div>
</div>
</td>
</tr>
</table>
</div>
<div class="footer">
<p>Copyright &copy; 1999-2013 <a class="external" href="http://www.apache.org">Apache Software Foundation</a>. All Rights Reserved.</p>
<p>Apache Logging, Apache Log4j, Log4j, Apache, the Apache feather logo, and the Apache Logging project logo are trademarks of The Apache Software Foundation.</p>
<p>Site powered by <a class="external" href="http://twitter.github.com/bootstrap/">Twitter Bootstrap</a>. Icons from <a class="external" href="http://glyphicons.com/">Glyphicons Free</a>.</p>
</div>
</div>
</body>
</html>