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Java problem regex

Hello everyone, I’m new to java and need help. I need to capitalize the pronoun I in an input string and I was told a regex would help but I don’t know where to start. I already managed to do it using a replaceAll. However this doesn’t involve cases like «neither do I.» - input : i don’t know what i’m writing. Neither do i. Maria, i’ll let you know when i can. -output : I don’t know what I’m writing. Neither do I. Maria, I’ll let you know when I can.

6th Oct 2022, 7:44 AM
Loulou
9 Answers
+ 4
Hello. You asked for a solution with regular expressions. Here is how you can do it with Java. Pattern.compile("\\bi\\b"); To explain, you want to capture the character lowercase i when it is a single word. The \b control character means a word boundary, this includes whitespace and punctuation such as apostrophe and dot also. In Java, you need to double-escape the backslashes in the regexp control codes, so it looks a bit weird compared to other languages. The Pattern object represents a regular expression, the Matcher object applies this to a specific string (text). Then Matcher has the replaceAll method which does just what you want. https://docs.oracle.com/en/java/javase/17/docs/api/java.base/java/util/regex/Pattern.html https://code.sololearn.com/ctRRbsTKRgHq/?ref=app
7th Oct 2022, 2:38 PM
Tibor Santa
Tibor Santa - avatar
+ 1
Do you have the code to share? In your above text, it looks like you have a space between either your inverted commas ' or backticks ` and your letters.
6th Oct 2022, 9:48 AM
Ausgrindtube
Ausgrindtube - avatar
+ 1
You could do some if/else if checks to cover all bases and only capitalise the pronouns that way.
6th Oct 2022, 1:35 PM
Ausgrindtube
Ausgrindtube - avatar
+ 1
1.U can do a loop that will start with the idx=0 to idx=last-2of the string. 2.State a condition that if charAt(idx) =='i' and Character.isLetter(charAt(idx+1) ) == false. 3.one more condition if (chaAt(idx-1) == 'i' and charAt(idx-2) ==' '). 4 . Statement within the condition will be. A empty string declared out side the loop. Say string x=""; X+=Chracter.toUpperCase(charAt(idx) ) ; 5.else part X+= charAt(idx) ; Hope so it helpsm
7th Oct 2022, 5:17 AM
Suvam Ghosh
+ 1
Tibor Santa you are my savior!!! Thank you so so much!!!
7th Oct 2022, 7:14 PM
Loulou
0
That’s not really the problem, that was just an example. I have a space before and after the letter i on purpose because I need the pronoun i to be capitalized in the sentence but I don’t want to keep using replaceAll for each case. - input : i don’t know what i’m writing. Neither do i. Maria, i’ll let you know when i can. -output : I don’t know what I’m writing. Neither do I. Maria, I’ll let you know when I can.
6th Oct 2022, 1:14 PM
Loulou
0
I thought of that but I wanted a method with regex to shorten the code, thanks though!
6th Oct 2022, 4:53 PM
Loulou
0
Include in the question description a link to your code in Code Playground, and we will help find the problem and the solution. That said, you probably have a problem detecting words. Let's see what the code shows us.
7th Oct 2022, 1:43 AM
Emerson Prado
Emerson Prado - avatar
0
Thank you suvam ghosh, I’ll try that out!
7th Oct 2022, 6:57 AM
Loulou