Question

I’ve seen several examples on how to retrieve and remove strings between delimiters. However, I created a very simple test case and I’m getting the wrong output based on various examples. Why am I getting back the string I’d like to use as the search source instead of the string I’m searching?

String temp = "56.0 F (13.3C)";
String exp = "((^))";
String p = temp.replace(exp, "");
System.out.println("p=" + p); 

I get the string 56.0F (13.3C) as my output.

I am expecting to get 56.0F back.

I also tried to use the pattern matcher:

Pattern pattern = Pattern.compile(exp);
Matcher matcher = pattern.matcher(temp);
if (matcher.find()) {
    System.out.println(matcher.groupCount());
    for (int i=0; i<=matcher.groupCount(); i++) {
        String groupStr = matcher.group(i);
        System.out.println(groupStr);
    }
}

2 is what’s printed to the console

Any ideas as to what I’m doing wrong? I’ve been looking at this now for a couple of hours. Thanks!

Answer 1

It is returning the string because it could not do any replacements.

Try using \(.*?\) or \([^)]*\) to match the portion of the string surrounded by parenthesis inclusive.

If you want it to optionally eat up surrounding whitespace, put a \s* either side of the regex, or do a trim on the result.