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Explanation of the metacharacter '\B' in Java regular expressions

Sub-expression/Meta-character " \B Matching with non-word boundary.

Example1

import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class RegexExample {
   public static void main(String args[]) {
      String regex = \\\\Bcause;
      Scanner sc = new Scanner(System.in);
      System.out.println("Enter a string: ");
      String input = sc.nextLine();
      Pattern p = Pattern.compile(regex);
      Matcher m = p.matcher(input);
      int count = 0;
      while(m.find()) {
         count ++;
      }
      System.out.println("Number of matches: ");+count);
   }
}

Output result

Enter a string:
A sentence doesn't end with because because, because is a conjunction
Number of matches: 3

Example2

import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Example {
   public static void main(String args[]) {
      System.out.println("Enter input string: ");
      Scanner sc = new Scanner(System.in);
      String input = sc.nextLine();
      String regex = "\\B";
      //Compiling the regular expression
      Pattern pattern = Pattern.compile(regex);
      //Retrieving the matcher object
      Matcher matcher = pattern.matcher(input);
      int count = 0;
      System.out.println("Non-word boundaries: ");
      while(matcher.find()) {
         count ++;
      }
      System.out.println(count);
   }
}

Output result

Enter input string:
Hello, how are you? Welcome to the w3codebox
Non-word boundaries:
30