public static void main(String [] args){
  String attachFile="D:\\aaa.txt";
  String virtualFileName="";
  
  File file = new File(attachFile);
  String suffix = attachFile.substring(attachFile.lastIndexOf("."));

  UUID uuid = UUID.randomUUID();     //生成序列号
  virtualFileName = uuid.toString();
  
  String path = "D:/apache-tomcat-5.5.20/attachFiles";
  virtualFileName = path + File.separator + virtualFileName + suffix;
  File targetFile = new File(virtualFileName);
  
  try {
   FileUtils.copyFile(file, targetFile);
  } catch (IOException e) {
   e.printStackTrace();
  }
 }