log4j

http://blog.csdn.net/u013516035/article/details/41686627

http://blog.csdn.net/sinat_30185177/article/details/73550377

注意    log4j.rootLogger = 输出位置

获取log4j.propeties文件的位置：String path = Log4j.class.getClass().getResource("/").getPath();

import java.util.Properties;
import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator;
public class Log4j {
    public static void main(String[] args) {
        String path = Log4j.class.getClass().getResource("/").getPath();
        System.out.println(path); 
        Logger logger = Logger.getLogger(Log4j.class.getName());
        Properties props=new Properties();  
        PropertyConfigurator.configure(path+"/config/log4j.properties");
        logger.debug("Debug ...");
        logger.info("Info ...");
        logger.warn("Warn ...");
        logger.error("Error ...");
    }
}