How to print the hierarchy of directory in Java

Problem Description

How to print the hierarchy of directory?

Solution

Following example shows how to print the hierarchy of a specified directory using file.getName() and file.listFiles() method of File class.

import java.io.File;
import java.io.IOException;

public class FileUtil {
   public static void main(String[] a)throws IOException{
      showDir(1, new File("d:\\Java"));
   }
   static void showDir(int indent, File file) throws IOException {
      for (int i = 0; i < indent; i++) System.out.print('-');
      System.out.println(file.getName());
      if (file.isDirectory()) {
         File[] files = file.listFiles();
         for (int i = 0; i < files.length; i++)showDir(indent + 4, files[i]);
      }
   }
}

Result

The above code sample will produce the following result.

-Java
-----codes
---------string.txt
---------array.txt
-----tutorial

The following is an another sample example of hierarchy of directory in Java

import java.io.File;
import java.io.IOException;

public class FileUtil {
   public static void main(String[] a)throws IOException { 
      showDir(1, new File("C:\\Users\\TutorialsPoint7\\Desktop"));
   } 
   static void showDir(int indent, File file) throws IOException { 
      for (int i = 0; i < indent; i++)System.out.print('-'); 
      System.out.println(file.getName());
      
      if (file.isDirectory()) {
         File[] files = file.listFiles();
         for (int i = 0; i < files.length; i++)showDir(indent + 4, files[i]); 
      } 
   }
}

The above code sample will produce the following result.

-Desktop
-----abc.png
-----abc.txt
-----bbc.txt
-----Custom CSS.txt
-----desktop.ini