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How to get the content of a directory?

In this example you'll see how to read the list of files inside a directory. To get this functionality we can use the File.listFiles() method. This method return an array of File object which can be either an instance of file or directory.



public class DirectoryContentExample
    public static void main(String[] args)
        File games = new File("D:\Games");

        // Get a list of file under the specified directory
        // above and return it as an abstract file object.
        File[] files = games.listFiles();

        // Iterates the content of games directory, print it
        // and check it whether it was a directory or a file.
        for (File file : files)
            System.out.println(file + " is a " 
                    + (file.isDirectory() ? "directory" : "file"));

        // Here we also get the list of file in the directory but
        // return it just as an array of String.
        String[] xfiles = games.list();
        for (String file : xfiles)
            System.out.println("File = " + file);

        // Now we want to list the file in the directory but
        // we just want a file with a .doc extension. To do
        // this we first create a FilenameFilter which will
        // be given to the listFiles() method to filter the
        // listing process. The rule of filtering is
        // implemented in the accept() method of the
        // FilenameFilter interface.
        FilenameFilter filter = new FilenameFilter()
            public boolean accept(File dir, String name)
                if (name.endsWith(".doc"))
                    return true;
                return false;

        // Give me just a .doc files in your directory.
        File[] yfiles = games.listFiles(filter);
        for (File doc : yfiles)
            System.out.println("Doc file = " + doc);

Here is the result of the program:

The File[] array returned:

D:GamesAOE is a directory
D:GamesChampionship Manager 2007 is a directory
D:GamesGameHouse is a directory
D:GamesSierra is a directory
D:Gamestesting.doc is a file
D:GamesTTD is a directory

The String[] array returned.

File = AOE
File = Championship Manager 2007
File = GameHouse
File = Sierra
File = testing.doc
File = TTD

The File[] array using FilenameFilter result.

Doc file = D:Gamestesting.doc