Dynamically configure the location of the log4j2.xml log output file

Goal: Dynamically modify the log location according to the parameters passed to main() when starting the jar

1. Modify the startup item 

MainMapLookup.setMainArguments(args); 
Note: Do not initialize the log before the lookup is set (eg: private static final Logger log = LoggerFactory.getLogger(HttpServer.class); )

1    public  static  void main(String[] args) throws InterruptedException, ServletException {
 2          // Set the log folder 
3          MainMapLookup.setMainArguments(args);
 4  
5          // Read the configuration file and start 
6          try {
 7              String confPathName = args[0 ];
 8              // Read the configuration file outside the jar 
9              InputStream in = new BufferedInputStream( new FileInputStream(confPathName+ "/conf.properties" ));
 10              config.load(in);
 11          }catch (Exception e) {
12             e.printStackTrace();
13         }
14         new HttpServer().start();
15     }

2. Set log4j2.xml

　　${main:0}

　　

The lo4j2.xml code is as follows

1  <? xml version="1.0" encoding="UTF-8" ?> 
2  
3  <!-- 
4      status : This is used to set the internal information output of log4j2 itself. Various detailed outputs inside
 log4j2 5      monitorInterval : Log4j can automatically detect modifying the configuration file and reconfigure itself, setting the interval in seconds.
6  --> 
7  < Configuration status ="DEBUG" monitorInterval ="6000" > 
8  
​​9      < Properties > 
10          <!-- Configuration log file output directory --> 
11          < Property name ="LOG_HOME" value ="log/log_ ${main:0}" 
         Property name ="LOG_NAME" > http </ Property > 
13      </ Properties > 
14  
15      < Appenders > 
16  
17          <!-- Configuration of this output console --> 
18          < Console name ="Console" target ="SYSTEM_OUT" > 
19              <!-- The console only outputs information of level and above (onMatch), other directly rejected (onMismatch) --> 
20              < ThresholdFilter level = "trace" onMatch = "ACCEPT" onMismatch = "DENY"/>
21             <!-- 输出日志的格式 -->
22             <PatternLayout pattern="%d{yyyy-MM-dd HH:mm:ss.SSS} %-5level %class{36} %L %M - %msg%xEx%n"/>
23         </Console>
24 
25         <!-- DEBUG日志格式 -->
26         <RollingFile name="service_debug_appender" fileName="${LOG_HOME}/${LOG_NAME}.log"
27                      filePattern="${LOG_HOME}/${LOG_NAME}.log.%d{yyyy-MM-dd}-%i" append="true" immediateFlush="true">
28             <Filters>
29                 < ThresholdFilter level ="trace" onMatch ="ACCEPT" onMismatch ="DENY" /> 
30              </ Filters > 
31              <!-- 
32                  %d{yyyy-MM-dd HH:mm:ss, SSS} : log production time
 33                  %p : log output format
 34                  %c : logger name
 35                  %m : log content, that is, logger.info("message")
 36                  %n : newline
 37                  %C : Java class
 name38                  %L : where the log output is located Line number
 39                  %M : Method name where log output is located
 40                  hostName :
local machine name 41                 hostAddress : 本地ip地址
42              -->
43             <PatternLayout>
44                 <pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} %-5level %class{36} %L %M -- %msg%xEx%n</pattern>
45             </PatternLayout>
46             <Policies>
47                 <TimeBasedTriggeringPolicy interval="1" modulate="true"/>
48                 <SizeBasedTriggeringPolicy size="500 MB"/>
49             </Policies>
50         </RollingFile>
51 
52 
53         <!-- ERROR日志格式 -->
54         <RollingFile name="service_error_appender" fileName="${LOG_HOME}/${LOG_NAME}.error"
55                      filePattern="${LOG_HOME}/${LOG_NAME}.error.%d{yyyy-MM-dd}-%i" append="true" immediateFlush="true">
56             <Filters>
57                 <ThresholdFilter level="error" onMatch="ACCEPT" onMismatch="DENY"/>
58             </Filters>
59             <PatternLayout>
60                 <pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} %-5level %class{36} %L %M -- %msg%xEx%n</pattern>
61             </PatternLayout>
62             <Policies>
63                 <TimeBasedTriggeringPolicy interval="1" modulate="true"/>
64                 <SizeBasedTriggeringPolicy size="500 MB"/>
65             </Policies>
66         </RollingFile>
67     </Appenders > 
68  
69      < Loggers > 
70          <!-- The root node of the configuration log --> 
71          < Root level = "debug" > 
72              < appender-ref ref = "Console" /> 
73              < appender-ref ref = "service_debug_appender" " /> 
74              < appender-ref ref ="service_error_appender" /> 
75          </ Root > 
76  
77          <!-- Third Party Logging System --> 
78          <logger name="org.springframework" level="INFO"/>
79         <logger name="io.netty" level="warn"/>
80         <logger name="org.apache.http" level="warn"/>
81         <logger name="org.mongodb.driver" level="INFO"/>
82         <logger name="org.jboss.netty" level="warn"/>
83         <logger name="org.springframework.data.redis" level="INFO"/>
84 
85     </Loggers>
86 
87 </Configuration>

View Code

3. Results

　　The log_${main:0} folder is generated under the log folder, and the system logs are placed under it