Regex to split a string on the basis of comma in Java

Question

I have a string from a csv file which I want to split. The string may contain a comma within a double quote or within a JSON. For example if the string is:

abc, pq"r,s", {"one":1, "two":2}

The regex should split it into three tokens as:

1. abc
2. pq"r,s"
3. {"one":1, "two":2}

I have tried this regex .

The regex reads like this: (?x)[,](?=([^"]*"[^"]*")*[^"]*$)

Can anyone please suggest a right regex?

Answer 1

Here is the regex that works on your example abc, pq"r,s", {"one":1, "two":2} :

,(?=(?:[^\"]*\"[^\"]*\")*[^\"]*$)(?=(?:[^{}]*{[^{}]*})*[^}]*$)

Or check out this regex101 example

There are three parts on this regex

1. , is the comma we want to match
2. (?=(?:[^\\"]*\\"[^\\"]*\\")*[^\\"]*$) is a look ahead based on the topic discussion Java: splitting a comma-separated string but ignoring commas in quotes by Bart Kiers.
3. (?=(?:[^{}]*{[^{}]*})*[^}]*$) is an adapted look ahead to handle { ... } .

Not sure if it will work on other examples.