final value into parameter

package com.concretepage;

public class finalValueIntoParameter {

void method1(String j) {
j = j + "1";
System.out.println(j);
}
void method2(final StringBuffer sb) {
StringBuffer sb2 = sb.append("100 again");
//sb2 = sb.append("100 again");
System.out.println(sb);
System.out.println(sb2);
}

public static void main(String[] args) {
    /*
        String str = "journaldev";

//string to char array
char[] chars = str.toCharArray();
System.out.println(chars.length);

//char at specific index
char c = str.charAt(2);
System.out.println(c);

//Copy string characters to char array
char[] chars1 = new char[7];
str.getChars(0, 3, chars1, 0);
System.out.println(chars1);
*/


     
        String s1 = "Welcome to Javatpoint"; 
        char[] ch = s1.toCharArray(); 
        int len = ch.length; 
        System.out.println("Char Array length: " + len); 
        System.out.println("Char Array elements: "); 
        for (int i = 0; i < len; i++) { 
            System.out.println(ch[i]); 
        }
 
/*
finalValueIntoParameter f = new finalValueIntoParameter();
    f.method1("100");
    f.method2(new StringBuffer("121"));
*/




}

}