Java - string.split with colliding regexes

mettleap :

I recently came across this problem and don't know how to solve it. I know that in the String class, we have the split method which accepts a regex and based on the regex, the given string is split into different strings and returned in a string array.

For example, if I have,

String s = "A,B,C";

and I do,

System.out.println(Arrays.toString(s.split(",")));

it will print [A, B, C] to output console.

Now let's say my string is

String s = "A,\"\"B\"\",\"\"C\"\",D";   //easier to read version: A,""B"",""C"",D

and I use the following regex to split the string,

String regex = ",|,\"\"|\"\",|\"\",\"\"";  // matches , OR ,"" OR "", OR "",""
System.out.println(Arrays.toString(s.split(regex)));

I get the output as [A, ""B, ""C, D]. How is the splitting working over here? And how do I define my regex so that I get [A, B, C, D] as my output?

NOTE: I know what I want to achieve can be done in other ways (like replaceAll method), but I only want to use the String.split for this problem, since I want to know how to use it in this case.

Toto :

Always order the alternatives from the largest to the smalest:

String regex = "\"\",\"\"|,\"\"|\"\",|,";