How to list directories, subdirectories and files using java

Hi everyone, I welcome to my post. Today I want to show you some codes using java language to list directories, subdirectories, and  files. You can see my as below:

package com.saretsothea.files.classwork;

import java.io.File;
import java.util.Scanner;

/**
 *
 * @author Sout Saret
 */
public class ListFiles{
   public static void main(String [] args){
       Scanner sc = new Scanner(System.in);
       String folder;
       System.out.print("Please the path of folder:");
       folder =sc.nextLine();
       System.out.println("List all directories, subdirectries and files:");
       File f = new File(folder);
       System.out.println(f.getName());
       listFile(folder);
    }
  
    public static void listFile(String folder){
        try{
            File f = new File(folder);
            File[] listOfFiles = f.listFiles();
                for(int i = 0; i < listOfFiles.length; i++) {
                  if (listOfFiles[i].isFile()) {
                    System.out.println("--" + listOfFiles[i].getName());
                  } else if (listOfFiles[i].isDirectory()) {
                    System.out.println("-"+listOfFiles[i].getName());
                    listFile(listOfFiles[i].getAbsolutePath());
                  }
                }
        }catch(NullPointerException e){}
   }  

}

Thanks for reading!!!!!!!!!!!!!!