How to set additivity to false when the Appender is added programatically - log4j

Question

I am new to log4j. My requirement is to create a new log file during every iteration. Basically during every iteration, below is what I need to attain:
Create a folder with current timestamp as the folder's name
Create a log file with name log.txt
Log the transactions of that iteration in log.txt
I have given a mock up of the implementation i need.
log4j.properties
log4j.rootLogger=INFO
log4j.appender.tracerLog=org.apache.log4j.FileAppender
log4j.appender.tracerLog.File=logs/${log4j.test.start.timestamp}/tracer.log
log4j.appender.tracerLog.layout=org.apache.log4j.PatternLayout
log4j.appender.tracerLog.layout.ConversionPattern=%d %-5p - %m%n
log4j.category.traceLogger=TRACE, tracerLog
log4j.additivity.traceLogger=false
java code
package app.testscript;
import java.text.SimpleDateFormat;
import java.util.Date;
import org.apache.log4j.FileAppender;
import org.apache.log4j.LogManager;
import org.apache.log4j.Logger;
import org.apache.log4j.PatternLayout;
public class Log4jTest {
static{
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyyMMdd_hh_mm_ss_S");
System.setProperty("log4j.test.start.timestamp", dateFormat.format(new Date()));
}
Logger traceLogger = Logger.getLogger("traceLogger");
Logger rootLogger = Logger.getRootLogger();
Logger testScriptLogger = null;
public void doSomething() {
try {
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyyMMdd_hh_mm_ss_S");
PatternLayout patterLayout = new PatternLayout("%m%n");
String folderNameToCreate = dateFormat.format(new Date());
FileAppender fileAppender = new FileAppender(patterLayout, "C:/MyTestLog/" + folderNameToCreate + "/log.txt", true);
fileAppender.setName("A" + folderNameToCreate);
fileAppender.activateOptions();
rootLogger.addAppender(fileAppender);
try {
testScriptLogger = LogManager.getLogger("A" + folderNameToCreate);
}catch(Exception e1) {
System.out.println("Exception e: ");
e1.printStackTrace();
}
//testScriptLogger.setAdditivity(false);
testScriptLogger.info("Message to capture in log - " + folderNameToCreate);
}catch(Exception e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
Log4jTest obj = new Log4jTest();
for (int i=0; i<2; i++) {
obj.doSomething();
try {
Thread.sleep(2000);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
Result of the above Code:
I can see there are 2 folders created (folder_1 and folder_2)
Both the folders have the log.txt in it
log.txt file created (inside folder_1) during iteration 1 have 2 lines in it (log related to iteration 1 and iteration 2)
log.txt file created (inside folder_2) during iteration 2 have one line it (log related to iteration 2)
Expected Result is to have 1 line in both the log.txt files (created during iteration 1 and 2)
When using testScriptLogger.setAdditivity(false); , I get the below WARNING message and nothing is written to the file.
log4j:WARN No appenders could be found for logger (A20170518_03_49_10_802).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
Please help me with a solution. Thanks

Answer 1

Found the answer.
Java code:
package app.testscript;
import java.text.SimpleDateFormat;
import java.util.Date;
import org.apache.log4j.FileAppender;
import org.apache.log4j.Logger;
import org.apache.log4j.PatternLayout;
public class Log4jTest {
static{
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyyMMdd_hh_mm_ss_S");
System.setProperty("log4j.test.start.timestamp", dateFormat.format(new Date()));
}
Logger scriptLogger = Logger.getLogger("scriptLogger");
String prevAppenderName = "";
public void removeBaseAppenderConfiguredInlog4jProperties() {
scriptLogger.removeAppender("scriptLog");
}
public void doSomething() {
try {
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyyMMdd_hh_mm_ss_S");
PatternLayout patterLayout = new PatternLayout("%m%n");
String folderNameToCreate = dateFormat.format(new Date());
FileAppender fileAppender = new FileAppender(patterLayout, "C:/MyTestLog/" + folderNameToCreate + "/log.txt", true);
fileAppender.setName("A" + folderNameToCreate);
fileAppender.activateOptions();
if(!prevAppenderName.equalsIgnoreCase("")) {
scriptLogger.removeAppender(prevAppenderName);
}
scriptLogger.addAppender(fileAppender);
prevAppenderName="A" + folderNameToCreate;
scriptLogger.setAdditivity(false);
scriptLogger.info("Message to capture in log - " + folderNameToCreate);
}catch(Exception e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
Log4jTest obj = new Log4jTest();
obj.removeBaseAppenderConfiguredInlog4jProperties();
for (int i=0; i<2; i++) {
obj.doSomething();
try {
Thread.sleep(2000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}