为什么我的 log4j 消息没有出现在日志文件中?

how come my log4j messages do not appear in log file?

我创建了log4j.properties文件,放在/src/main/resources/下面,这个文件的内容是:

log4j.rootLogger = DEBUG, FILE
log4j.appender.FILE=org.apache.log4j.FileAppender
log4j.appender.FILE.File=log.out
# Set the immediate flush to true (default)
log4j.appender.FILE.ImmediateFlush=true

# Set the threshold to debug mode
log4j.appender.FILE.Threshold=debug

# Set the append to false, overwrite
log4j.appender.FILE.Append=false

# Define the layout for file appender
log4j.appender.FILE.layout=org.apache.log4j.PatternLayout
log4j.appender.FILE.layout.conversionPattern=%m%n

我想查看文件 log.out 中的日志,但是当我 运行 使用以下命令的应用程序时:

java -jar myapp.jar -Dlog4j.debug

文件未创建。

这是——按照评论中的要求——我在代码中使用它的方式:

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

private static final Logger LOG = LogManager.getLogger(MyClass.class);

及以后:

LOG.debug("some message");

LOG.error("some other msg", error);

请在下面找到实现:

log4j.properties

在`

src/main/resources

`

# Root logger option
log4j.rootLogger=INFO, stdout, file

# Redirect log messages to console
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n

# Redirect log messages to a log file
log4j.appender.file=org.apache.log4j.RollingFileAppender
#outputs to Tomcat home
log4j.appender.file.File=D:/demo/logs/myapp/myapp.log
log4j.appender.file.MaxFileSize=5MB
log4j.appender.file.MaxBackupIndex=10
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n

除此之外,我还在 class 中导入了 Logger

package org.nbk.demo;
import org.apache.log4j.Logger;
public class ServerStartup {
    private static final Logger logger = Logger.getLogger(ServerStartup.class);
    public void onApplicationEvent() {
            logger.info("Information Messages");
    }
}