Configuring log4j2 for threads

Question

There is a class called Test, which extends from Thread. How do I configure log4j2 so that for each Test thread my own log file is created.

I'm trying to do this:

public class Test extends Thread {

private String name;

private Logger LOGGER;

public Test(String name) {
    this.name=name;
}

@Override
public void run() {

    System.setProperty("taskLogFolder", Global.getInstance().getLogRoot().toString());
    System.setProperty("taskLogName", name);

    LoggerContext loggerContext = Configurator.initialize(name, new File(Global.getInstance().getAppRoot()+WEB_INF_DIR+"taskLog4j2.xml").toString());

    LOGGER = loggerContext.getLogger(name);

    for(int i=0;i<100;i++) {
        LOGGER.info(LOGGER.getName()+" "+i);
    }

    //LOGGER.info(LOGGER.getName());

}

}

But at startup one file is output.

new Test("task-8").start();
new Test("task-2").start();
new Test("task-3").start();
new Test("task-4").start();
new Test("task-5").start();
new Test("task-6").start();
new Test("task-7").start();

Earlier I used log4j and there I did it, but I do not understand how.

What am I doing wrong?

taskLog4j2.xml file:

    <?xml version="1.0" encoding="UTF-8"?>
<Configuration status="info" monitorInterval = "30">

    <Properties>
        <Property name="pattern">%d{yyyy-MM-dd HH:mm:ss.SSS} [%level] [thread-id %T] %l - %msg%n</Property>
    </Properties>

    <Appenders>
        <RollingFile name="fileLogger" fileName="${sys:taskLogFolder}/${sys:taskLogName}.log" filePattern="${sys:taskLogFolder}/${sys:taskLogName}-%d{yyyy-MM-dd}.log">
            <PatternLayout>
                <pattern>${pattern}</pattern>
            </PatternLayout>
            <Policies>
                <TimeBasedTriggeringPolicy interval="1" modulate="true" />
            </Policies>
        </RollingFile>

        <Console name="console" target="SYSTEM_OUT">
            <PatternLayout pattern="${pattern}" />
        </Console>
    </Appenders>

    <Loggers>
        <Root level="info" additivity="false">
            <appender-ref ref="console" />
            <appender-ref ref="fileLogger" />
        </Root>
        <Logger name="com.test.*" level="info">
            <appender-ref ref="fileLogger" level="info" />
        </Logger>
    </Loggers>

</Configuration>

for @Sudheera answer

2017-12-12 22:22:46,942 task-3 ERROR Unable to invoke factory method in class org.apache.logging.log4j.core.appender.RollingFileAppender for element RollingFile: java.lang.IllegalStateException: No factory method found for class org.apache.logging.log4j.core.appender.RollingFileAppender java.lang.IllegalStateException: No factory method found for class org.apache.logging.log4j.core.appender.RollingFileAppender
at org.apache.logging.log4j.core.config.plugins.util.PluginBuilder.findFactoryMethod(PluginBuilder.java:229)
at org.apache.logging.log4j.core.config.plugins.util.PluginBuilder.build(PluginBuilder.java:134)
at org.apache.logging.log4j.core.config.AbstractConfiguration.createPluginObject(AbstractConfiguration.java:958)
at org.apache.logging.log4j.core.config.AbstractConfiguration.createConfiguration(AbstractConfiguration.java:898)
at org.apache.logging.log4j.core.appender.routing.RoutingAppender.createAppender(RoutingAppender.java:271)
at org.apache.logging.log4j.core.appender.routing.RoutingAppender.getControl(RoutingAppender.java:255)
at org.apache.logging.log4j.core.appender.routing.RoutingAppender.append(RoutingAppender.java:225)
at org.apache.logging.log4j.core.config.AppenderControl.tryCallAppender(AppenderControl.java:156)
at org.apache.logging.log4j.core.config.AppenderControl.callAppender0(AppenderControl.java:129)
at org.apache.logging.log4j.core.config.AppenderControl.callAppenderPreventRecursion(AppenderControl.java:120)
at org.apache.logging.log4j.core.config.AppenderControl.callAppender(AppenderControl.java:84)
at org.apache.logging.log4j.core.config.LoggerConfig.callAppenders(LoggerConfig.java:448)
at org.apache.logging.log4j.core.config.LoggerConfig.processLogEvent(LoggerConfig.java:433)
at org.apache.logging.log4j.core.config.LoggerConfig.log(LoggerConfig.java:417)
at org.apache.logging.log4j.core.config.LoggerConfig.log(LoggerConfig.java:403)
at org.apache.logging.log4j.core.config.AwaitCompletionReliabilityStrategy.log(AwaitCompletionReliabilityStrategy.java:63)
at org.apache.logging.log4j.core.Logger.logMessage(Logger.java:146)
at org.apache.logging.log4j.spi.AbstractLogger.tryLogMessage(AbstractLogger.java:2116)
at org.apache.logging.log4j.spi.AbstractLogger.logMessageSafely(AbstractLogger.java:2100)
at org.apache.logging.log4j.spi.AbstractLogger.logMessage(AbstractLogger.java:1994)
at org.apache.logging.log4j.spi.AbstractLogger.logIfEnabled(AbstractLogger.java:1966)
at org.apache.logging.log4j.spi.AbstractLogger.info(AbstractLogger.java:1303)
at com.test.Test.run(Test.java:20)

Answer 1

You can write a Log4J config plugin for custom name lookup and use it through a router configuration. Here's the fixed code for you. I have added Log4jThreadLookup class for look up the thread name from the log4j config context. Just make sure this class is available in the class path. I also changed the configuration file and the Test class as well.

Log4jThreadLookup class

package com.test;

import org.apache.logging.log4j.core.LogEvent;
import org.apache.logging.log4j.core.config.plugins.Plugin;
import org.apache.logging.log4j.core.lookup.StrLookup;

@Plugin(name = "thread", category = StrLookup.CATEGORY)
public class Log4jThreadLookup implements StrLookup {

    public String lookup(String key) {
        return Thread.currentThread().getName();
    }

    public String lookup(LogEvent event, String key) {
        return event.getThreadName();
    }

}

Configuration

<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="info" monitorInterval = "30">

    <Properties>
        <Property name="pattern">%d{yyyy-MM-dd HH:mm:ss.SSS} [%level] [thread-id %T] %l - %msg%n</Property>
    </Properties>

    <Appenders>
        <Routing name="Routing">
            <Routes pattern="$${thread:threadName}">
                <Route>
                    <RollingFile name="logFile-${thread:threadName}"
                                 fileName="logs/tasks-${thread:threadName}.log" filePattern="logs/tasks-${thread:threadName}-%d{yyyy-MM-dd}.log">
                        <PatternLayout>
                            <pattern>${pattern}</pattern>
                        </PatternLayout>
                        <Policies>
                            <TimeBasedTriggeringPolicy interval="1" modulate="true" />
                        </Policies>
                    </RollingFile>
                </Route>
            </Routes>
        </Routing>
        <Console name="console" target="SYSTEM_OUT">
            <PatternLayout pattern="${pattern}" />
        </Console>
    </Appenders>

    <Loggers>
        <Root level="info" additivity="false">
            <appender-ref ref="console" />
            <appender-ref ref="Routing" />
        </Root>
        <Logger name="com.test.*" level="info">
            <appender-ref ref="Routing" level="info" />
        </Logger>
    </Loggers>

</Configuration>

Test class

package com.test;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

public class Test extends Thread {

    private static final Logger LOGGER = LogManager.getLogger(Test.class);
    private final String name;

    public Test(String name) {
        this.name = name;
    }

    @Override
    public void run() {
        Thread.currentThread().setName(name);

        for (int i = 0; i < 100; i++) {
            LOGGER.info(LOGGER.getName() + " " + i);
        }

    }
}