Regular Expression: No match found?

Question

This is what I am trying to do...

Enter Pattern
//*//_//*
Enter Text
hello *_* how are you?
No match found

I know to avoid treating above characters as Metacharacters I need to use these escape sequences. I don't know how to do with _ (underscore sigh)

I even tried

//* _ //*

Still it didn't work.

code

Scanner sc = new Scanner(System.in);
System.out.println("Enter pattern");
Pattern pattern = Pattern.compile(sc.nextLine());
System.out.println("Enter Text");
Matcher matcher = pattern.matcher(sc.nextLine());
boolean found = false;

while(matcher.find())
{
    System.out.println("I found the text" + matcher.group() + "Starting index" + matcher.start() + "Ending at index" + matcher.end());
    found = true;
}
if(!found)
{
    System.out.println("No match found");
}

Post the code that you tried – Mustapha Belmokhtar Nov 27 '17 at 08:48 — Mustapha Belmokhtar, Nov 27 '17 at 08:48

score -1 · Answer 1 · answered Nov 27 '17 at 08:49

-1

If you are trying to match the *_* part of the input, try the following pattern:

\*\_\*

answered Nov 27 '17 at 08:49

Matt Clegg

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But for java shouldn't I be putting double backslashes? – dexter Nov 27 '17 at 08:53
@dexter Do not escape word chars, an underscore is a word char. `\_` = `_` in Java regex. – Wiktor Stribiżew Nov 27 '17 at 08:55
@WiktorStribiżew Alright, But as you can see I putting it without that. But still didn't work! – dexter Nov 27 '17 at 08:59
@dexter `Pattern.quote("*_*")` will do if you need to pass literal text to a regex compiler. – Wiktor Stribiżew Nov 27 '17 at 09:01

Regular Expression: No match found?

1 Answers1