日志4J2LogManager.getLogger()线程安全吗?

java.util.logger ,所有3个日志事件都已成功发布。

   public class TestLoggingMDC
    {
        public static void main( String[] args ) throws InterruptedException
        {
            System.setProperty( "log4j.configurationFile", "log4j2.xml" );//set path here to log4j2 config file

            ExecutorService executor = Executors.newFixedThreadPool( 3 );
            TestLoggingMDC testLoggingMDC = new TestLoggingMDC();

            for ( int i = 0; i < 3; i++ )
            {
                Runnable runnableTask = testLoggingMDC::calculate;
                executor.execute( runnableTask );
            }

            executor.awaitTermination( 5, TimeUnit.SECONDS );

        }

        public void calculate()
        {
            //java.util.logging.Logger.getLogger( "testMDC" ).info( "total is ..." );//this works. log 3 time
            LogManager.getLogger( ).info( "total is ..." );//this does not

        }

}

当我同步计算方法时 public synchronized void calculate() 或者得到一个类锁,如下面所示,它可以正常工作。

public  void calculate()
    {
        synchronized ( LogManager.class )
        {
            LogManager.getLogger().info( "total is ..." );
        }

    }

LogManager.getLogger() 线程不安全吗?还是我错过了什么?

请注意,我尝试在没有 ExecutorService 使用 java.lang.Thread ),结果相同。

• IntelliJ Idea 2018.1.5

log4j2配置文件:

<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="INFO">
    <Appenders>
        <Console name="ConsoleAppender" target="SYSTEM_OUT">
            <PatternLayout pattern="%d{HH:mm:ss,SSS} [%t] %-5p %c{36} - %m%n"/>
        </Console>
        <File name="fileAppender" fileName="out/MDCTest.log">
            <PatternLayout>
                <Pattern>%X{id} %m%n</Pattern>
            </PatternLayout>
        </File>
    </Appenders>
    <Loggers>
        <Root level="INFO">
            <AppenderRef ref="ConsoleAppender"/>
        </Root>
        <Logger name="testMDC" level="ALL">
            <AppenderRef ref="fileAppender"/>
        </Logger>
    </Loggers>
</Configuration>