log4j学习记录

今天项目要一个servlet，log4j的应用，边学边做。

 

应用还是很简单的，配件文件：

 

log4j.appender.R=org.apache.log4j.RollingFileAppender
log4j.appender.R.File=${cashlessLog4jPath}/WEB-INF/logs/cashless.log
log4j.appender.R.MaxBackupIndex=10
log4j.appender.R.MaxFileSize=20KB

log4j.appender.R.layout=org.apache.log4j.PatternLayout
log4j.appender.R.layout.ConversionPattern=%d [%t] %-5p %-17c{2} (%13F\:%L) %3x - %m%n

log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d [%t] %-5p %-17c{2} (%13F\:%L) %3x - %m%n

#log4j.appender.D=org.apache.log4j.DailyRollingFileAppender
#log4j.appender.D.DatePattern=
log4j.logger.com.dpc=debug,stdout,R

 

关键的两个包：

import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator;

 

类：

public class LogService {  
    private Logger loger;  
    private static LogService log;  

    private LogService()  
    {  
        String filePath=this.getClass().getResource("/").getPath();  
        filePath=filePath.substring(1);
        loger=Logger.getLogger(this.getClass());  
        PropertyConfigurator.configure(filePath+"log4j.properties");  
    }  
      
    static LogService getLoger()  
    {  
        if(log!=null){
        	 return log;  
        } else {
        	return new LogService();  
        }
    }  
      
    //测试方法:
    public static void log( String msg )  
    {  
    	LogService log=LogService.getLoger();  
        log.loger.error( msg );
    }
}