I need some help with this question in java:

You may assume the user will enter a one line properly formatted post fixed math expression, with the tokens (operators and operands) separated by white space. You should use the API Stack class and the StringTokenizer class. Declare your Stack object to be a stack that can only store objects in the class Double.

Below is an outline of the program.

import java.util.*; // needed for the StringTokenizer class

import javax.swing.*;

// Declare a Java API Stack object that can store Double objects (See page 168)

// Accept the users input of the math String into the variable mathExpression

// Evaluate the math expression[1] // see the code template in Exercise 21, page 171

// Pop the stack and output the returned value

[1] Be sure to parse the numeric operands to doubles before pushing them onto the stack

below is the code template given in excercise 21, page 171:

import java.util;

String thisToken;

StringTokenizer tokens = new StringTokenizer(mathExpression);

while(tokens.hasMoreTokens())

{ thisToken = tokens.nextToken();

// processing for thisToken goes here

}

Thank you any help is appreacted.