Java – In java, how to write logs to a specific file appender of log4j

javalog4jlogging

If a log4j properties have multiple file appenders, then in Java how can I make sure that logs are written in a specific file.

log4j.rootLogger=INFO,out 

log4j.appender.SUCCESS_FILE=org.apache.log4j.FileAppender
log4j.appender.SUCCESS_FILE.File=${dd.log.dir}/success.log

log4j.appender.VALID_FILE=org.apache.log4j.FileAppender
log4j.appender.VALID_FILE.File=${dd.log.dir}/valid_error.log

log4j.appender.TEMP_FILE=org.apache.log4j.FileAppender
log4j.appender.TEMP_FILE.File=${dd.log.dir}/Temp_error.tmp_log

In Java class, what can I do to write some messages to, lets say, SUCCESS_FILE and some messages to TEMP_FILE

Logger log = Logger.getLogger(Test.class);
log.debug("This message should go to SUCCESS_FILE");
log.debug("This message should go to TEMP_FILE");

Best Answer

This might help:-

log4j.appender.successLog=org.apache.log4j.FileAppender
log4j.appender.successLog.File=${dd.log.dir}/success.log

log4j.appender.tempLog=org.apache.log4j.FileAppender
log4j.appender.tempLog.File=${dd.log.dir}/Temp_error.tmp_log

log4j.category.successLogger=INFO, successLog
log4j.additivity.successLogger=false

log4j.category.tempLogger=INFO, tempLog
log4j.additivity.tempLogger=false

Access them like:-

static final Logger successLog = Logger.getLogger("successLogger");
static final Logger tempLog = Logger.getLogger("tempLogger");

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