原本tomcat的日志格式如下：<Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs" prefix="localhost_access_log." suffix=".txt" pattern="%h %l %u %t "%r" %s %b" resolveHosts="false"/>
我们要在日志中显示时间的话，需要添加%T：
<Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs"
prefix="localhost_access_log." suffix=".txt"
pattern="%h %l %u %t %T "%r" %s %b" resolveHosts="false"/>下面表是tomcat日志格式各值代表的意思：
Values Description
- %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 hostname (or IP address if enableLookups for the connector isfalse)
- %H Request protocol
- %l Remote logical username from identd
- %m Request method (GET, POST, and so on)
- %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)
- %U Requested URL path
- %v Local server name
- %D Time taken to process the request, in milliseconds
- %T Time taken to process the request, in seconds
- %I Current request thread name (can compare later with stack t