Regular Expression Metacharacter in Java

The subexpression/metacharacter “\t” matches the tab spaces.

Example 1

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 = "\t";       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 tab spaces: "+count);    } }

Output

Enter a string: This    is    a    sentence    with    tab    spaces Number of tab spaces: 6

Example 2

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 = "\t";       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;       String result = "";       while(m.find()) {          result = m.replaceAll(" ");       }       System.out.println("Result: "+result);    } }

Output

Enter a string: This is a sentence with tab spaces Result: This is a sentence with tab spaces