I need some help writting this code for a java program that needs modified to follow these instructions! Hope someone can help! Thanks!!

Here is a skeleton of a program. The GUI is written you must add the functionality.

SimpleCalc.java

You must hand in a single file named Calculator.java for your project-07 submission.

It will not, cannot be script graded. It will be checked for compilation success at handin time.

This skeleton program must be enhanced as follows:

-Your implementation of actionListener will contain your code that responds to button clicks or text entries on the calculator's surface.

-You muat allow entries using either the keys or by typing text into the expression text field.

-The CE button must clear the last operand entered while the C button must clear the entire expression textfield

-The equals button must calculate the result and write the resulting value into the result textfield. You must write the evaluation function. We will discuss this in class. Your evaluation must evaluate each operator for it's true precedence. This little bit of logic will take some work!

-Dont worry about bad expressions. Your code only needs to work on any valid expression.

-Here is an illustration of how you can extract the operators/operands from an expression String: Tokenize.java

Tokenize.java Code:

import java.util.*; import java.io.*; public class Tokenize { public static void main( String[] args) { // Stolen directly from stackoverflow with just a few mods :) String expr="4+5-12/3.5-5.4*3.14"; // replace with any expression to test System.out.println( "expr: " + expr ); ArrayList operatorList = new ArrayList(); ArrayList operandList = new ArrayList(); // StringTokenizer is like an infile and calling .hasNext() StringTokenizer st = new StringTokenizer( expr,"+-*/", true ); while (st.hasMoreTokens()) { String token = st.nextToken(); if ("+-/*".contains(token)) operatorList.add(token); else operandList.add(token); } System.out.println("Operators:" + operatorList); System.out.println("Operands:" + operandList); } } 

Code for SimpleCalc.java that needs to be modified with the above instructions!

code that needs fuctionality added:

// Demonstrates JPanel, GridLayout and a few additional useful graphical features. // adapted from an example by john ramirez (cs prof univ pgh) import java.awt.*; import java.awt.event.*; import javax.swing.*; public class SimpleCalc { JFrame window; // the main window which contains everything Container content ; JButton[] digits = new JButton[12]; JButton[] ops = new JButton[4]; JTextField expression; JButton equals; JTextField result; public SimpleCalc() { window = new JFrame( "Simple Calc"); content = window.getContentPane(); content.setLayout(new GridLayout(2,1)); // 2 row, 1 col ButtonListener listener = new ButtonListener(); // top panel holds expression field, equals sign and result field // [4+3/2-(5/3.5)+3] = [3.456] JPanel topPanel = new JPanel(); topPanel.setLayout(new GridLayout(1,3)); // 1 row, 3 col expression = new JTextField(); expression.setFont(new Font("verdana", Font.BOLD, 16)); expression.setText(""); equals = new JButton("="); equals.setFont(new Font("verdana", Font.BOLD, 20 )); equals.addActionListener( listener ); result = new JTextField(); result.setFont(new Font("verdana", Font.BOLD, 16)); result.setText(""); topPanel.add(expression); topPanel.add(equals); topPanel.add(result); // bottom panel holds the digit buttons in the left sub panel and the operators in the right sub panel JPanel bottomPanel = new JPanel(); bottomPanel.setLayout(new GridLayout(1,2)); // 1 row, 2 col JPanel digitsPanel = new JPanel(); digitsPanel.setLayout(new GridLayout(4,3)); for (int i=0 ; i  Simple Calc CE  Simple Calc CE