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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

Java

// 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());
        }
    }
}

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"

Java

// 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());
        }
    }

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

File list() method in Java with Examples

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