Tomcat日志格式自定义

Tomcat⽇志格式⾃定义
设置⽇志显⽰信息格式，默认情况下，Tomcat的访问⽇志是不记录的。

需要在serve.xml中修改配置，去掉注释。

<!--
<Valve className="org.apache.catalina.valves.AccessLogValve"
directory="logs" prefix="localhost_access_log." suffix=".txt"
pattern="common" resolveHosts="false"/>
-->
将注释去掉即可。

如果要调整⽇志记录的字段，需要修改pattern属性值，common是默认的属性，其值为： %h %l %u %t %r %s %b 各符号表⽰为（下⾯描述摘⾃Tomcat官⽅⽂档）：
* %a - Remote IP address
* %A - Local IP address
* %b - Bytes sent, excluding HTTP headers, or '-' if zero
* %B - Bytes sent, excluding HTTP headers
* %h - Remote host name (or IP address if resolveHosts is false)
* %H - Request protocol
* %l - Remote logical username from identd (always returns '-')
* %m - Request method (GET, POST, etc.)
* %p - Local port on which this request was received
* %q - Query string (prepended with a '?' if it exists)
* %r - First line of the request (method and request URI)
* %s - HTTP status code of the response
* %S - User session ID
* %t - Date and time, in Common Log Format
* %u - Remote user that was authenticated (if any), else '-'
* %U - Requested URL path
* %v - Local server name
* %D - Time taken to process the request, in millis
* %T - Time taken to process the request, in seconds
There is also support to write information from the cookie, incoming header,
the Session or something else in the ServletRequest. It is modeled after the apache syntax:
* %{xxx}i for incoming headers
* %{xxx}c for a specific cookie
* %{xxx}r xxx is an attribute in the ServletRequest
* %{xxx}s xxx is an attribute in the HttpSession
通常情况下，为便于分析⽹站瓶颈，将pattern=“%h %l %u %t "%r" %s %b %D”，其中D代表处理该请求所消耗的毫秒数，如此可以⽅便找到问题，提⾼系统性能。

/s/blog_6c9a9a870100m2ak.html
/uid-20691565-id-3938220.html。