Java - Regex String replacement

Question

I want to replace some parts of a String with Regex. It's the 192001Z part of the string I want to replace.

Code:

String met = "192001Z 17006KT 150V210 CAVOK 11/07 Q1004 NOSIG";
String regexZ = "[0-9].{5}Z";
met = met.replaceAll(regexZ, "${.now?string(\"ddHHmm\")}Z");

I get an error when I want to replace a part of the String with ${.now?string(\"ddHHmm\")}Z.

But when I e.g. replace ${.now?string(\"ddHHmm\")}Z with ThisNeedsToBeReplaced everything works just fine. So my guess is that something is wrong with the string I want to use to replace parts of my original string (met).

The error I receive is Illegal group reference.

Does anyone have an idea what's wrong with ${.now?string(\"ddHHmm\")}Z?

Answer 1

You need to use:

met = met.replaceAll("\\b\\d{6}Z\\b", "\\${.now?string(\"ddHHmm\")}Z");

• Correct regex to match 192001Z is \b\d{6}Z\b
• You need to escape $ in replacement as well otherwise it is considered a back reference e.g. 1,ドル 2ドル etx.

• Maroun: Shouldn't . be escaped as well?
• Avinash Raj: yep, escaping the $ will do the job.
• anubhava: @MarounMaroun: DOT has no special meaning in replacement but $ does have.
• Steven Verheyen: Escaping the $ did the job! Thanks!!