How to split multi-line string in Java

Question

I have the following data text :

[data]A[/data] aaa 4 5 8 [data]B[/data] bbb 3 1 9 [data]C[/data] ccc 6 5 2 ...

I want to split them in to the following 3 units :

1st unit :

[data]A[/data] aaa 4 5 8

2nd unit :

[data]B[/data] bbb 3 1 9

3rd unit :

[data]C[/data] ccc 6 5 2

So my code looks like this :

String Units[]=dataText.split("[data]");

Yet, this doesn't do it properly, what's the right way to split it ?

If I use regex, how should I write the expression ?

Possible duplicate of Java String.split() Regex

Van_Cleff
– Van_Cleff

2019-03-01 20:53:04 +00:00
Commented Mar 1, 2019 at 20:53 — Van_Cleff
– Van_Cleff, Commented Mar 1, 2019 at 20:53

Andreas · Accepted Answer · 2019-03-01 21:12:12Z

Use regex (?ms)(?<=.)(?=^\[):

 String[] units = dataText.split("(?ms)(?<=.)(?=^\\[)");

See regex101.com for demo.

Explanation:

(?ms) Turn on MULTILINE ('^' and '$' match after/before line terminator) and DOTALL (aka "single line", '.' matches any character) (?<=.) Must be preceded by a character (needs 's' flag) Used to prevent matching very first '[' (?=^\[) Must be followed by a '[' at the beginning of a line (needs 'm' flag)

Christian Huber · Accepted Answer · 2019-03-01 21:32:18Z

1

You could use a BufferedReader:

BufferedReader br = new BufferedReader(new StringReader(dataString));

Iterate the String like this:

int lineCounter = 0; int arrayCounter = 0; String line = null; while( (line = br.readLine()) != null ) { units[arrayCounter] += line; if (lineCounter >= 2) { arrayCounter++; lineCounter = 0; } }