Check if a path represents a file or a folder

java

file-system

path-api

file-operations

byAnton Shumikhin·Sep 15, 2024

Determine the type of a Path (file or directory) with **Files.isDirectory(Path)** and Files.isRegularFile(Path):

import java.nio.file.*;

Path path = Paths.get("your/path/here");  // Replace with your actual path
if (Files.isDirectory(path)) {
    System.out.println("Congratulations! You've found a directory 📁");
} else if (Files.isRegularFile(path)) {
    System.out.println("Voila! It's a file 📄");
} else {
    System.out.println("Oops! Neither a file nor a directory 😕");
}

To prevent any NullPointerException, ensure path is not null before running these checks.

Detecting non-existent paths

When a path is non-existent, Files.isDirectory(Path) and Files.isRegularFile(Path) return false. Here's how you handle this:

if (!Files.exists(path)) {
    System.out.println("I'm Sherlock, and even I can't find this path 🔍");
} else {
    // Insert the checks from the fast answer here
}

Also, a path might be a symbolic link or other collateral entities. Configure how symbolic links should be treated:

import java.nio.file.*;

if (Files.isDirectory(path, LinkOption.NOFOLLOW_LINKS)) {
    // Look Ma, no symbolic link! We found a real directory 😎
} else if (Files.isRegularFile(path, LinkOption.NOFOLLOW_LINKS)) {
    // Eureka! It's a tangible file, not a symbolic link 🥳
}

Deciding between the File and Path APIs

While java.io.File was the OG, it has shortcomings with handling symbolic links and file attributes. The new kid on the block, java.nio.file.Files, offers better compatibility across various platforms. So, prefer the shiny new Path and Files classes for efficient filesystem manipulation.

Tips and common pitfalls

Jedi code warriors handle their exceptions. Wrap your checks within a try-catch block to manage potential IOExceptions:

try {
    // Insert file/directory check logic here
} catch (IOException ex) {
    System.out.println("IOException occurred. Did you try turning it off and on again? 🤓");
    // Handle error gracefully
}

And when you think you're smart enough to identify directories by the lack of an extension, remember:

Directories can be sly foxes and contain periods ('.') in their names.
Make your methods return a boolean to write a piece of script Bill Gates would be proud of!
Use clear application logic while determining what constitutes a 'file' or 'directory' - or you'll be forever stuck in the rabbit hole.

explain-codes / Java / Check if a path represents a file or a folder

Linked

How to check if a folder exists?



How do I check if a file exists in Java?



How do I iterate through the files in a directory and its sub-directories in Java?



How to create a directory in Java?



How to read all files in a folder from Java?

