import java.io.*;

class FileRename {
      public static void main(String[] args) {
            if (args.length != 1) {
                  System.out.println("Usage: java FileRename directory");
                  System.exit(0);
            }

            File dir = new File(args[0]);
            File[] list = dir.listFiles();

            for (int i = 0; i < list.length; i++) {
                  String fileName = list[i].getName();
                  // 파일명
                  String newFileName = "0000" + fileName;
                  newFileName = newFileName.substring(newFileName.length() - 7);
                  list[i].renameTo(new File(newFileName));
            }
      } // end of main

} // end of FileRename class

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