How to extract characters and numbers from an Alphanumeric value

import java.util.Scanner;

public class AlphanumericStr {

	public static void main(String[] args) {
		// TODO Auto-generated method stub

		Scanner inpAlphaNumeric = new Scanner (System.in);
		StringBuilder strNumbers=new StringBuilder();
		StringBuilder strLetters=new StringBuilder();
		System.out.println("Enter an alpha numeric string (Ex:- 381BY4kjLpq6)");
		String inpStr=inpAlphaNumeric.next();
		int idx=0,strLen=inpStr.length();

		while (--strLen >= 0) {
			if(Character.isAlphabetic(inpStr.charAt(idx))) 
				strLetters.append(inpStr.charAt(idx));
			else
				if(Character.isDigit(inpStr.charAt(idx)))
					strNumbers.append(inpStr.charAt(idx));
			idx++;
		}
		inpAlphaNumeric.close();
		System.out.println("The string of characters extracted from "+inpStr+" is="+strLetters.toString());
		System.out.println("The string of numbers extracted from "+inpStr+" is="+ Integer.valueOf(strNumbers.toString()));
		System.out.println("Add 1 to the Extracted number "+Integer.valueOf(strNumbers.toString())+" + "+"1="+(Integer.valueOf(strNumbers.toString())+1));
	}
}