How to replace last dot in a string using a regular expression?

Question

I\'m trying to replace the last dot in a String using a regular expression.

Let\'s say I have the following String:

String string = \"hello.world.how         


        

Answer 1

The regex you need is \\.(?=[^.]*$). the ?= is a lookahead assertion

"hello.world.how.are.you!".replace("\\.(?=[^.]*$)", "!")