Loop to access specific files?

Question

I have 700 files in one folder, each one with a number 1-700, with the file extension .pkmn. I created them and changed their data with a program, but now how would I access them? I've tried a for loop with the path + i + ".pkmn", but it didn't work. How would I access them and assign them to a File?

Thank you.

Didn't work? Do you get an error? Can you show us the code as well as location of files, pattern of file name. — Raf, Dec 08 '15 at 12:06
Please show your code and the error message, exceptions. "but it didn't work" is not very helpfull. — vanje, Dec 08 '15 at 12:07
You can try with: `File[] files = new File("directory").listFiles()` — Valijon, Dec 08 '15 at 12:07
Possible duplicate of [Read all files in a folder](http://stackoverflow.com/questions/1844688/read-all-files-in-a-folder) — Raf, Dec 08 '15 at 12:10

andrucz · Answer 1 · 2015-12-08T12:14:07.023

1

You can use listFiles() method, that returns an array of files in a directory:

File directory = new File("directory path");
File[] createdFiles = directory.listFiles();
for (File createdFile : createdFiles) {
     ...
}

edited Dec 08 '15 at 12:14

answered Dec 08 '15 at 12:07

andrucz

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score 1 · Answer 2 · answered Dec 08 '15 at 12:14

You should use the methods of java nio file instead of the "old" io package! It is much faster.

Path dir = ...;
try (DirectoryStream<Path> stream = Files.newDirectoryStream(dir)) {
    for (Path file: stream) {
        System.out.println(file.getFileName());
    }
} catch (IOException | DirectoryIteratorException x) {
    // IOException can never be thrown by the iteration.
    // In this snippet, it can only be thrown by newDirectoryStream.
    System.err.println(x);
}

https://docs.oracle.com/javase/tutorial/essential/io/dirs.html#listdir

Loop to access specific files?

2 Answers2