Log：日志工具输出log的使用

　　日志的简单使用，三种方式。

1. org.apache.commons.logging.Log

   //import org.apache.commons.logging.Log;
   //import org.apache.commons.logging.LogFactory;
   private static final Log log = LogFactory.getLog(xxxServiceImpl.class);
   
   log.info(Object msg);

2. log4j 1.x 版本：org.apache.log4j.Logger

   //org.apache.log4j.Logger;
   private final Logger logger = Logger.getLogger(this.getClass());
   
   logger.info(Object msg);

3. log4j 2.x 版本：org.apache.logging.log4j.Logger

   private static final Logger logger = LogManager.getLogger(xxxClass.class);
   
   logger.info(String msg);

示例：创建一个基本服务类，里面放有Logger对象

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * 创建一个基本Service类，存放Logger对象，
 * 基它业务类继承可直接拿来用
 * @author Rocky
 *
 */
public class BaseService {
	
	/**
     * 日志对象
     */
    protected Logger logger = LoggerFactory.getLogger(getClass());
    
}