如何用Java重命名一个文件夹的所有文件？

Input : Read 50 files from the folder
"C:\Users\Anannya Uberoi\Desktop\myfolder":
Snapshot 1 (12-05-2017 11-57).png
Snapshot 2 (12-05-2017 11-57).png
Snapshot 3 (12-05-2017 11-57).png
Snapshot 4 (12-05-2017 11-57).png and so on.
Output :Renamed to
1.png
2.png
3.png
4.png and so on.


// Java program to illustrate
// how to rename Multiple Files
// together using single program
import java.io.File;
import java.io.IOException;
public class rename
{
    public static void main(String[] argv) throws IOException
    {
        // Path of folder where files are located
        String folder_path =
               "C:\\Users\\Anannya Uberoi\\Desktop\\myfolder";
        // creating new folder
        File myfolder = new File(folder_path);
        File[] file_array = myfolder.listFiles();
        for (int i = 0; i < file_array.length; i++)
        {
            if (file_array[i].isFile())
            {
                File myfile = new File(folder_path +
                         "\\" + file_array[i].getName());
                String long_file_name = file_array[i].getName();
                String[] tokens = long_file_name.split("\\s");
                String new_file_name = tokens[1];
                System.out.println(long_file_name);
                System.out.print(new_file_name);
                // file name format: "Snapshot 11 (12-05-2017 11-57).png"
                // To Shorten it to "11.png", get the substring which
                // starts after the first space character in the long
                // _file_name.
                myfile.renameTo(new File(folder_path +
                             "\\" + new_file_name + ".png"));
            }
        }
    }
}


The files get renamed successfully.