Java File mkdir()

In this guide, you will learn about the File mkdir() method in Java programming and how to use it with an example.

1. File mkdir() Method Overview

Definition:

The mkdir() method of the File class is used to create a directory denoted by the abstract pathname of the File object. If the parent directories do not exist, the directory will not be created.

Syntax:

public boolean mkdir()

Parameters:

None.

Key Points:

- The method will create only the directory denoted by the File object's abstract pathname.

- It will return true if and only if the directory was successfully created; false will be returned otherwise.

- If the parent directories do not exist, the directory will not be created.

- No exception is thrown if the directory couldn't be created. Instead, a boolean value is returned to indicate success or failure.

- If a file or directory already exists with the specified name, the directory will not be created.

2. File mkdir() Method Example

import java.io.File;

public class FileMkdirExample {
    public static void main(String[] args) {
        // Creating a File object for a directory
        File directory = new File("path/to/directory/newDirectory");

        // Creating the directory
        boolean isCreated = directory.mkdir();

        if (isCreated) {
            System.out.println("Directory was successfully created.");
        } else {
            System.out.println("Failed to create the directory. It might already exist or its parent directory might not exist.");
        }
    }
}

Output:

Directory was successfully created.
OR
Failed to create the directory. It might already exist or its parent directory might not exist.

Explanation:

In the provided example, a File object, directory, is created representing a specific directory. 

Invoking the mkdir() method on this object attempts to create the directory denoted by the File object's abstract pathname. If the directory is successfully created, a success message is printed out to the console. If not, a failure message is shown, indicating potential reasons for the failure such as the directory already existing or its parent directory not existing.