Question

I need to split a string on any of the following sequences:

1 or more spaces
0 or more spaces, followed by a comma, followed by 0 or more spaces,
0 or more spaces, followed by “=>”, followed by 0 or more spaces

Haven’t had experience doing Java regexs before, so I’m a little confused. Thanks!

Example:
add r10,r12 => r10
store r10 => r1

Answer 1

Just create regex matching any of your three cases and pass it into split method:

string.split("\\s*(=>|,|\\s)\\s*");

Regex here means literally

1. Zero or more whitespaces (\\s*)
2. Arrow, or comma, or whitespace (=>|,|\\s)
3. Zero or more whitespaces (\\s*)

You can replace whitespace \\s (detects spaces, tabs, line breaks, etc) with plain space character if necessary.