Pattern Matching

[Sudharsan Ashwin]

   
package pack.generics;
import java.util.regex.*;

public class RegEx {
public static void main(String [] args) {
System.out.println("Next");
	String regex ="(b-d)*";
	String match = "b-db-db-d";
	Pattern p1 = Pattern.compile(regex);
	Matcher m1 = p1.matcher(match);
	while(m1.find()) {
		System.out.print(m1.start() + " ");
	}
}
 

I am getting output as "0 9", but the length of the string match is 9.
Can anyone explain?

Myself

[Ankit Garg]

Since you've written (b-d)*, so there will be an empty match at the end of the string as * means 0 or more occurrences of something...

[Frits Walraven]

Ankit is correct, so if you change it into (+ means one or more occurences)

String regex = "(b-d)+";    

you will get:
0

or into:

String regex = "(b-d)";    

you will get:
0 3 6