log4j日志文件的编写

刚开始出现这个问题可把我给搞疯了

需要添加日志配置文件和jar包
1）添加log4j和slf4j-log4j12的jar包，在maven中引入依赖

        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-core</artifactId>
            <version>2.11.0</version>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-log4j12</artifactId>
            <version>1.7.12</version>
        </dependency>

2）编写log4j.properties文件
输出级别：FATAL>ERROR>WARN>INFO>DEBUG，如果你的lenel设定为INFO，那么不能输出DEBUG信息；
其中我将我的日志信息输出到了D:/flowerU/myLog/mylog.log

log4j.rootLogger=INFO, stdout,logfile
# Console output...
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n

log4j.appender.logfile=org.apache.log4j.DailyRollingFileAppender
log4j.appender.logfile.datePattern='-'dd'.log'
log4j.appender.logfile.File=D:/flowerU/myLog/mylog.log
log4j.appender.logfile.layout=org.apache.log4j.PatternLayout
log4j.appender.logfile.layout.ConversionPattern=%-6r %d{ISO8601} %-5p %40.40c %x - %m\n


##log4j.logger.yui.bss.mgr.ext.cabt.ConnLogMgrxImpl=INFO, myappender

##log4j.appender.myappender=org.apache.log4j.DailyRollingFileAppender
##log4j.appender.myappender.datePattern='-'dd'.log'
##log4j.appender.myappender.File=D:/flowerU/myLog/mylog.log
##log4j.appender.myappender.layout=org.apache.log4j.PatternLayout
##log4j.appender.myappender.layout.ConversionPattern=%-6r %d{ISO8601} %-5p %40.40c %x - %m\n

关于日志文件的编写
推荐一篇博客Log4j.properties 属性详解以及 LOG4J日志级别详解 - CSDN博客 https://blog.csdn.net/zouxucong/article/details/54894123

关于日志文件的实例编写，日志文件的类型，推荐
Log4j appender输出类型配置 - 汪强胜 - 博客园 https://www.cnblogs.com/wqsbk/p/6817886.html

在编码中输出日志信息

@Aspect
@Component
public class MyLog {
    private static final Logger logger=LoggerFactory.getLogger(UserServiceImpl.class);
     @Before("execution(* com.wjh.service.impl.UserServiceImpl.login(..))")
        public void loginLog(){
            logger.info("user login");
        }

}