Java IO package (java.io) provides class named File which is abstraction of file and directory names. This class provides an abstract, system independent view of path names. The following sample Java program prints a list of files and folders in a specified directory. The program also uses File attributes to indicate whether a directory entry is a file or a directory. Use the isFile() method to distinguish between files and directories.

If you are running this example on a Linux system, replace the rootFolder variable value with an appropriate path such as /home/user/.

Getting List of Files in a Directory in Java

import java.io.File;

public class FileDemo {

    public static void main(String[] args) {
        String rootFolder = "c:\\";
        File aFile = new File(rootFolder);
        System.out.println("Type      | Name");
        for(File file: aFile.listFiles()) { // Java 5 style for loop
            System.out.print(file.isFile()? "File     ":"Directory");
            System.out.print(" | ");
            System.out.println(file.getName() );
        }
    }
    
}

Note that listFiles() method returns everything including hidden files and folders. You can use the isHidden() method to check whether a file or folder is hidden in the file system. You can also use the File class to create directories, rename files/folders or to delete files and folders.

Since Java 7, java.nio.file package provides better handling of file systems and file attributes. If you are supporting Java 7 and above only use this package as it is more reliable.