获取文件大小

    public static void main(String[] args) {  
        File f= new File("D:\\CentOS-6.5-x86_64-bin-DVD1.iso");  
        if (f.exists() && f.isFile()){  
            logger.info(f.length());  
        }else{  
            logger.info("file doesn't exist or is not a file");  
        }  
    }