How to Separate Letters and Symbols from String.(Almost Done)

import java.util.Scanner;

public class Separate {

   public static void main(String[] args) {
         Scanner user_input = new Scanner( System.in ); 
    String variable;
    System.out.print("Enter Variable:");
      variable = user_input.next();
          Separate(variable);
   }

   public static void Separate(String str) {
          String number = "";
          String letter = "";
      String symbol = "";
          for (int i = 0; i < str.length(); i++) {
                 char a = str.charAt(i);
                 if (Character.isDigit(a)) {
                       number = number + a;

                 } else {
                       letter = letter + a;


         }
          }
          System.out.println("Alphabets in string:"+letter);
          System.out.println("Numbers in String:"+number);   
   }

}

Okay, i already have this code which separate the Numbers and Letters that i Input. The problem is, when ever i input Symbols for example (^,+,-,%,*) it also states as a Letter.

What i want to do is to separate the symbol from letters just like what i did on Numbers and Letters and make another output for it.

You are testing if the character isDigit, else treat it as a letter. Well, if it is not a digit, all other cases go to else, in your code. Create an else case for those symbols also.