Splitting a string that has escape sequence using regular expression in Java

Question

String to be split

abc:def:ghi\:klm:nop

String should be split based on ":" "\" is escape character. So "\:" should not be treated as token.

split(":") gives

[abc]
[def]
[ghi\]
[klm]
[nop]

Required output is array of string

[abc]
[def]
[ghi\:klm]
[nop]

How can the \: be ignored

Answer 1

Use a look-behind assertion:

split("(?<!\\\\):")

This will only match if there is no preceding \. Using double escaping \\\\ is required as one is required for the string declaration and one for the regular expression.