java - Log4j getAllAppenders() returns null enumeration -

i trying file name of log4j log file. tried solution given in following answer.

https://stackoverflow.com/a/4401387/1015678

enumeration e = logger.getrootlogger().getallappenders(); while ( e.hasmoreelements() ){   appender app = (appender)e.nextelement();   if ( app instanceof fileappender ){     system.out.println("file: " + ((fileappender)app).getfile());   } } 

but, logger.getrootlogger().getallappenders() returns null enumeration. (i took care use rootlogger mentioned in answer)

following log4j2.xml

<?xml version="1.0" encoding="utf-8"?> <configuration status="debug">     <properties>         <!-- used if log_file_name env variable not set  -->         <property name="log_file_name">my_app_log</property>     </properties>     <appenders>         <rollingfile name="rollingfile-${web:contextpath}"                      filename="${sys:catalina.base}/logs/${env:log_file_name}.log" immediateflush="true"                      filepattern="${sys:catalina.base}/logs/${env:log_file_name}.log.%d{yyyy_mm_dd.hh_mm_ss}">             <patternlayout pattern="%d{yyyymmdd-hhmmss.sss}|%-5p|%t| %-100m (%c{1})%n"/>             <policies>                 <onstartuptriggeringpolicy/>             </policies>         </rollingfile>     </appenders>     <loggers>         <root level="debug" includelocation="false">             <appenderref ref="rollingfile-${web:contextpath}"/>         </root>     </loggers> </configuration> 

any idea why?

i did grep on whole source of apache-log4j-2.3-src getallappenders , found in 1 place getting implemented.

in category.java

@suppresswarnings("rawtypes") public enumeration getallappenders() {     return nullenumeration.getinstance(); } 

the above method returns enumeration having no elements in it.

the other in loggertest.java, execute test case.

/**  * add appender , see if can retrieved.  *  skipping test appender interface isn't compatible legacy log4j. public void testappender1() {     logger = logger.getlogger("test");     a1 = new listappender("testappender1");     logger.addappender(a1);      enumeration enumeration = logger.getallappenders();     appender ahat = (appender) enumeration.nextelement();     assertequals(a1, ahat); } */  /**  * add appender x, y, remove x , check if y  * remaining appender.  * skipping test appender interface isn't compatible legacy log4j. public void testappender2() {     a1 = new fileappender();     a1.setname("testappender2.1");     a2 = new fileappender();     a2.setname("testappender2.2");      logger = logger.getlogger("test");     logger.addappender(a1);     logger.addappender(a2);     logger.removeappender("testappender2.1");     enumeration enumeration = logger.getallappenders();     appender ahat = (appender) enumeration.nextelement();     assertequals(a2, ahat);     asserttrue(!enumeration.hasmoreelements()); }  */ 

seeing above comments, looks deprecated, test case commented out. i'm not sure, tried find out if have declared anywhere, couldnt find.

so thought helpful, unless wasting time on debugging.

---

as explained in answer use getappenders api like

logger logger = logmanager.getlogger(); map<string, appender> appendermap =          ((org.apache.logging.log4j.core.logger) logger).getappenders();