使用String.split（）拆分时转义'，'分隔符

Question

I am trying to read a file and hence I am splitting the fields when I receive ',' comma separator . However some fields have ',' in them but they are enclosed within double quotes hence how can I split it escaping the , separator. Here is what I have done

String[] cols = line.split(Pattern.quote(","));

How should I modify this using split() only in Java. Also what changes will I have to make in case the separator is a pipe '|' ?

Answer 1

I answered a similar question here . The first expression, modified for your task, would read

,(?=([^"]*"[^"]*")*[^"]*$)

This expression identifies an unquoted comma by ensuring that an even number of quotation marks follows it.

Answer 2

I wouldn't try using a regex for this. Regular expressions are just not a great match for this - while it may be possible to create such a regex, it would be horrible to read.

There are plenty of open source CSV parsers. Just a quick search found many projects - I would look through those before writing your own.

Answer 3

    String  line="one|two,three";
    String cols[]= line.split("[,|\\|]");

Something like the above would split based on , and |

For meta-character | you would have to delimit with \\ \\ I agree with others; it's better to use CSV parsers out there rather than reinventing it again.