Question

How to to check if all the characters of a string are same in Java

Answer 1

public class MyClass {
    static boolean all_characters_are_the_same(String s) { 
        int len = s.length(); 
        
        for (int i = 1; i < len; i++) 
            if (s.charAt(i) != s.charAt(0)) 
                return false; 
              
        return true; 
    } 

    public static void main(String args[]) {
        String s = "aaaaa";
        
        if (all_characters_are_the_same(s)) 
            System.out.println("Yes"); 
        else
            System.out.println("No"); 
    }
}



/*
run:

Yes

*/

 

70+ SQL courses for beginners and professionals

Answer 2

public class MyClass {
    static boolean all_characters_are_the_same(String s) { 
        return s.chars().allMatch(ch -> ch == s.charAt(0));
    } 

    public static void main(String args[]) {
        String s = "aaaaa";
        
        if (all_characters_are_the_same(s)) 
            System.out.println("Yes"); 
        else
            System.out.println("No"); 
    }
}



/*
run:

Yes

*/

 

70+ SQL courses for beginners and professionals

Answer 3

import java.io.*;

public class MyClass {
    static boolean all_characters_are_the_same(String s) { 
        return s.replace(String.valueOf(s.charAt(0)), "").length() == 0;
    } 

    public static void main(String args[]) {
        String s = "aaaaa";
        
        if (all_characters_are_the_same(s)) 
            System.out.println("Yes"); 
        else
            System.out.println("No"); 
    }
}



/*
run:

Yes

*/

 

70+ SQL courses for beginners and professionals