JAVA

Postfix

The code below won't compile correctly. Error occuring on division of the 2nd expression. Please help find error.

import java.util.*;

public class Postfix {

public static void main(String[] args) {

int data1 = 1, data2 = 2, data3 = 4, data4 = 5, data5 = 3;

String expression = String.valueOf(data1) + String.valueOf(data2) + "+" + String.valueOf(data3) + "*" + String.valueOf(data4) + "-";

System.out.println("data1 data2 + data3 * data4 - = " + postfix(expression));

String expression2 = String.valueOf(data1) + String.valueOf(data2) + "*" + String.valueOf(data3) + "*" + String.valueOf(data1) + "-" + "/" + String.valueOf(data4) + String.valueOf(data5) + "*" + "+";

System.out.println("data1 data2 * data3 * data1-/ data4 data5*+= " + postfix(expression2));

}

public static int postfix(String postfix) {

Stack valuestack = new Stack ();

int characterCount = postfix.length();

int index = 0;

char nextChar = ' ';

Integer operandTwo, operandOne;

Integer result;

for(; index < characterCount; index++)

{

nextChar = postfix.charAt(index);

switch(nextChar)

{

case '+':

operandTwo = valuestack.pop();

operandOne = valuestack.pop();

result = operandOne + operandTwo;

valuestack.push((Integer)result);

break;

case '-':

operandTwo = valuestack.pop();

operandOne = valuestack.pop();

result = operandOne - operandTwo;

valuestack.push((Integer)result);

break;

case '*':

operandTwo = valuestack.pop();

operandOne = valuestack.pop();

result = operandOne * operandTwo;

valuestack.push((Integer)result);

break;

case '/':

operandTwo = valuestack.pop();

operandOne = valuestack.pop();

result = operandOne / operandTwo;

valuestack.push((Integer)result);

break;

default: String nextch = postfix.substring(index, index+1);

valuestack.push(Integer.parseInt(nextch));

break;

}

}

return valuestack.peek();

}

}