Android find a file with a pattern (regex)

Question

Suppose I have files like these in a folder:

• myfile_mark_1.mp4
• myfile_john_2.mp4
• myfile_jake_3.mp4
• myfile_tristan_4.mp4
• yourfile_mark_1.mp4

How do I find files where only the names containing "myfile_" in the prefix and suffix would be 3 or less("_3.mp4", "_2.mp4", "_1.mp4", something like this).

So in my program I could get:

• myfile_mark_1.mp4
• myfile_john_2.mp4 and
• myfile_jake_3.mp4

I have tried this one, hoping to get lucky but I didn't get any result. :D

String myDirectory = Environment.getExternalStorageDirectory().getAbsolutePath();
File f = new File(myDirectory);
if (f.exists() && f.isDirectory()){
    final Pattern p = Pattern.compile("myfile_*\\_(^0*(1?\\d|%d)$).mp4"); // I know I really have a stupid mistake on the regex;

    File[] flists = f.listFiles(new FileFilter(){
        @Override
        public boolean accept(File file) {
            return p.matcher(file.getName()).matches();
        }
    });

    String s = "wait a minute, i'm debugging";
}

I hope someone can help out on my problem.

Answer 1

The regex required is quite simple.

myfile_.*_[123]\\.mp4