Question

Is this the proper REGEX to remove trailing decimal and zeroes from a string? I can’t get it to work. What am I missing?

1. 78.000 -> 78
2. 78.008 -> 78.008

str.replaceAll("^.0*$", "");

Answer 1

You need to escape the ., as it is a special character in Regex that matches any character. You also have to remove the ^, which anchors at the beginning of the number.

str.replaceAll("\\.0*$", "");

You can use a lookbehind if you want to make sure there is a number in front of the dot, like this:

str.replaceAll("(?<=^\\d+)\\.0*$", "");

The lookbehind (the (?<=...) part) is not a part of the match, so it will not be replaced, but it still has to match for the rest of the regex to match.