清理Java中的文件名

Question

I want to write a script that will clean my .mp3 files. I was able to write a few line that change the name but I want to write an automatic script that will erase all the undesired characters $%_!?7 and etc. while changing the name in the next format Artist space dash Song .

    File file = new File("C://Users//nikita//Desktop//$%#Artis8t_-_35&Son5g.mp3");
    String Original = file.toString();
    String New = "Code to change 'Original' to 'Artist - Song'";
    File file2 = new File("C://Users//nikita//Desktop//" + New + ".mp3");
    file.renameTo(file2);

I feel like I should make a list with all possible characters and then run the String through this list and erase all of the listed characters but I am not sure how to do it.

String test = "$%$#Arti56st_-_54^So65ng.mp3";

Edit 1:

When I try using the method remove , it still doesn't change the name.

String test = "$%$#Arti56st_-_54^So65ng.mp3";
System.out.println("Original: " + test);
test.replace( "[0-9]%#&\\$", "");
System.out.println("New:      " + test);

The code above returns the following output

Original: $%$#Arti56st_-_54^So65ng.mp3
New:      $%$#Arti56st_-_54^So65ng.mp3

Answer 1

I'd suggest something like this:

public static String santizeFilename(String original){
    Pattern p = Pattern.compile("(.*)-(.*)\\.mp3");
    Matcher m = p.matcher(original);

    if (m.matches()){
        String artist = m.group(1).replaceAll("[^a-zA-Z ]", "");
        String song = m.group(2).replaceAll("[^a-zA-Z ]", "");

        return String.format("%s - %s", artist, song);
    }
    else {
        throw new IllegalArgumentException("Failed to match filename : "+original);
    }

}

(Edit - changed whitelist regex to exclude digits and underscores)

Two points in particular - when sanitizing strings, it's a good idea to whitelist permitted characters, rather than blacklisting the ones you want to exclude, so you won't be surprised by edge cases later. (You may want a less restrictive whitelist than I've used here, but it's easy to vary) It's also a good idea to handle the case that the filename doesn't match the expected pattern. If your code comes across something other than an MP3, how would you like it to respond? Here I've through an exception, so the calling code can catch and handle that appropriately.

Answer 2

String new = original.replace( "[0-9]%#&\\$", "")

this should replace almost all the characters you don't want

or you can come up with your own regex

https://docs.oracle.com/javase/tutorial/essential/regex/