如何为多个线程以编程方式创建单独的Log4j2滚动文件附加器和记录器

Question

因此，我希望以编程方式创建单独的appender和单独的logger，以便每个appender只附加到它自己的线程，然后在一个线程中创建的logger只在该线程中创建appender。

请让我知道如何一步步实现。

Answer 1

首先，这感觉像是一个XY问题，特别是因为您没有提供任何理由来说明为什么要使用编程解决方案。

可以在一个线程一个线程的基础上实现单独的日志文件，而不需要以编程方式创建记录器和附加器。由于我相信这是一个更优化的解决方案，我将提供一个演示如何可以这样做。

解释

<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="WARN">
    <Appenders>
        <Routing name="MyRoutingAppender">
            <Routes pattern="$${ctx:threadName}">
                <Route>
                    <File
                        fileName="logs/${ctx:threadName}/log.txt"
                        name="appender-${ctx:threadName}">
                        <PatternLayout>
                            <Pattern>[%date{ISO8601}][%-5level][%t] %m%n</Pattern>
                        </PatternLayout>
                    </File>
                </Route>
            </Routes>
        </Routing>
        <Console name="STDOUT" target="SYSTEM_OUT">
            <PatternLayout pattern="[%date{ISO8601}][%-5level][%t] %m%n" />
        </Console>
    </Appenders>
    <Loggers>
        <Logger name="Thread" level="TRACE" additivity="false">
            <AppenderRef ref="STDOUT" />
            <AppenderRef ref="MyRoutingAppender" />
        </Logger>
        <Root level="WARN">
            <AppenderRef ref="STDOUT" />
        </Root>
    </Loggers>
</Configuration>

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

public class MultiThreadLog4j2SepFilesMain {
    //Create a lock to use for synchronizing the getting of the logger
    private static final Object lock = new Object();

    public static void main(String[] args) {
        Thread t1 = new Thread(new Runnable(){

            public void run() {
                //Set up the context before getting logger
                ThreadContext.put("threadName", Thread.currentThread().getName());

                //Get the logger for this thread
                Logger log = null;
                synchronized(lock){
                    log = LogManager.getLogger(Thread.currentThread().getName());
                }

                //Generate some logs
                log.info("here's the first thread");

                //Wait a while so that threads interleave
                try {
                    Thread.sleep(1000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }

                //Generate more logs
                log.debug("some debug in first thread");
                log.info("finishing first thread");

            }}, "Thread.1"); //Use a name that will allow us to use Thread.getName when getting the logger inside the thread

        Thread t2 = new Thread(new Runnable(){

            public void run() {
                //Set up the context before getting logger
                ThreadContext.put("threadName", Thread.currentThread().getName());

                //Get logger for this thread
                Logger log = null;
                synchronized(lock){
                    log = LogManager.getLogger(Thread.currentThread().getName());
                }

                //Generate some logs
                log.info("here's the second thread");
                log.debug("some debug in second thread");

            }}, "Thread.2"); //Use a name that will allow us to use Thread.getName when getting the logger inside the thread

        //Start both threads
        t1.start();     
        t2.start();
    }
}