Java Directory - Directory and File Listing Example in Java

This example illustrates how to list files and folders present in the specified directory. This topic is related to the I/O (input/output) of java.io package.

In this example we are using File class of java.io package. The File class is an abstract representation of file and directory pathnames. This class is an abstract, system-independent view of hierarchical pathnames. An abstract pathname has two components:

An optional system-dependent prefix string,
such as a disk-drive specifier, "/" for the UNIX root directory, or "\\" for a Win32 UNC pathname, and
A sequence of zero or more string names.

Explanation

This program list the file of the specified directory. We will be declaring a function called dirlist which lists the contents present in the specified directory.

dirlist(String fname)

The function dirlist(String fname) takes directory name as parameter. The function creates a new File instance for the directory name passed as parameter

File dir = new File(fname);

and retrieves the list of all the files and folders present in the directory by calling list() method on it.

String[] chld = dir.list();

Then it prints the name of files and folders present in the directory.

Code of the Program :


import java.io.*;




 
public class  DirListing{

   private static void dirlist(String fname){


  File dir = new File(fname);

     String[] chld = dir.list();


  if(chld == null){


  System.out.println("Specified directory does not exist or is not a directory.");


  System.exit(0);

     }else{

   for(int i = 0; i < chld.length; i++){


  String fileName = chld[i];


  System.out.println(fileName);

   }

   }

   }


  public static void main(String[] args){

 
  switch(args.length){


  case 0: System.out.println("Directory has not mentioned.");

 
  System.exit(0);


  case 1: dirlist(args[0]);

   System.exit(0);


  default : System.out.println("Multiple files are not allow.");

     System.exit(0);

   }

   }


}

Download Directry Listing Example