I'm currently in an introductory level Java class, and am working on the classic phrase guess assignment. The object is for one user to enter a secret phrase, and another to guess it one letter at a time. Between guesses, the phrase must be displayed as all question marks except the letters that were guessed correctly. Our class has only really covered some very basic methods, if-else statements and loops up to this point, but I'm trying to research some string methods that may make this a bit easier.
I know of the replace()
, replaceAll()
and contains()
methods, but was wondering if there is a method which allows you to replace all but one character of your choice in a string.
Thanks in advance
The easiest way is probably to use String.replaceAll()
:
String out = str.replaceAll("[^a]", "?");
This will leave all letters a
intact and will replace all other characters with question marks.
This can be easily extended to multiple characters, like so:
String out = str.replaceAll("[^aeo]", "?");
This will keep all letters a
, e
and o
and will replace everything else.
The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.