File list() method in Java with Examples

The list() method is a part of File class.The function returns an array of string denoting the files in a given abstract pathname if the path name is a directory else returns null. The function is an overloaded function. One of the function does not have any parameter and the other function takes FilenameFilter object as parameter

Function Signature:

public String[] list()
public String[] list(FilenameFilter f)

Function Syntax:



file.list()
file.list(filter)

Parameters: The function is an overloaded function. One of the function does not have any parameter and the other function takes FilenameFilter object as a parameter

Return value: The function returns a string array, or null value if the file object is file.

Exception: This method throws Security Exception if the function is not allowed write access to the file.

Below programs will illustrate the use of the list() function

Example 1: We will try to find all the files and directories in a given directory

filter_none

edit
close

play_arrow

link
brightness_4
code

// Java program to demonstrate the
// use of list() function
  
import java.io.*;
  
public class solution {
    public static void main(String args[])
    {
  
        // try-catch block to handle exceptions
        try {
  
            // Create a file object
            File f = new File("f:\\program");
  
            // Get all the names of the files present
            // in the given directory
            String[] files = f.list();
  
            System.out.println("Files are:");
  
            // Display the names of the files
            for (int i = 0; i < files.length; i++) {
                System.out.println(files[i]);
            }
        }
        catch (Exception e) {
            System.err.println(e.getMessage());
        }
    }
}

chevron_right


Output:

Files are:
1232.txt
1245.txt
5671.txt
program1

Example 2: We will try to find all the files and directories in a given directory whose names start with “12”

filter_none

edit
close

play_arrow

link
brightness_4
code

// Java program to demonstrate the
// use of list() function
  
import java.io.*;
  
public class solution {
    public static void main(String atry-catch  {
  
        // try catch block to handle exceptions
        try {
  
            // Create a file object
            File f = new File("f:\\program");
  
            // Create a FilenameFilter
            FilenameFilter filter = new FilenameFilter() {
  
                public boolean accept(File f, String name)
                {
                    return name.startsWith("12");
                }
            };
  
            // Get all the names of the files present
            // in the given directory
            // and whose names start with "12"
            String[] files = f.list(filter);
  
            System.out.println("Files are:");
  
            // Display the names of the files
            for (int i = 0; i < files.length; i++) {
                System.out.println(files[i]);
            }
        }
        catch (Exception e) {
            System.err.println(e.getMessage());
        }
    }

chevron_right


Output:

Files are:
1232.txt
1245.txt

The programs might not run in an online IDE. please use an offline IDE and set the Parent file of the file



My Personal Notes arrow_drop_up

Second year Department of Information Technology Jadavpur University

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.