/**  
     * 重命名文件  
     * @param fileName  
     * @return  
     */   
    public static void renameFile(String filePath, String fileName) { 
        SimpleDateFormat fmdate = new SimpleDateFormat("yyyyMMddHHmmssSSS"); 
        String oldFileName = filePath+"/"+fileName; 
        File oldFile = new File(oldFileName); 
        String newFileName = filePath+"/"+fileName.split("//.")[0]+fmdate.format(new Date())+"."+fileName.split("//.")[1]; 
        File newFile = new File(newFileName); 
        if (oldFile.exists() && oldFile.isFile()) { 
            oldFile.renameTo(newFile); 
        } 
    }