Regex to replace empty value in a csv string in java

Question

I have a string with value

 "ABC","ONE", "Hello",,,"2019"

I want to replace two consecutively empty values in a CSV file with * .

Expected output:

 "ABC","ONE", "Hello","*","*","2019"

This is what I tried,

line.replaceAll(",,","\"*\"");

But this gives me below output, replacing on first occurrence

"ABC","ONE", "Hello","*","2019"

Answer 1

You may use a regex with lookahead and lookbehind:

(?<=,)(?=,)

And replace it with "*"

RegEx Demo

Java Code:

repl = str.replaceAll("(?<=,)(?=,)", "\"*\"");