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import java.io.*; import java.util.*; import javax.swing.*; import java.awt.*; import java.awt.event.*; public class CalculatorFrame2 extends JFrame { private Container contentPane; //The componenets used in the calculator private JTextField display; private JButton addition; private JButton subtract; private JButton multiply; private JButton divide; private JButton mod; private JButton enter; private JButton [] digits; //End of components //Integer representations for the arithmetic operations needed private final static int ADD = 1; private final static int SUB = 2; private final static int MUL = 3; private final static int DIV = 4; private final static int MOD = 5; //ENd of arithmethic operations //Integer holding the operator that the user requested private int op; //Boolean variable to help perform the calculations private boolean firstFilled; private boolean clearScreen; //Constructor for the class public CalculatorFrame() { contentPane=new Container(); this.setSize(400,300); //sets the size of the frame this.setTitle("MIS 222 Calculator"); //sets the title of the frame //allows the "X" box in the upper right hand corner to close the entire application this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); contentPane=this.getContentPane(); //gets the content pane //Methods addDisplay(); addDigits(); addDigitActionListeners(); addOperation(); } private void addDisplay() { JLabel displayLab = new JLabel("Answer"); JPanel north = new JPanel(); north.add(displayLab); contentPane.add(north, "north"); //diplay was already declared above the constructor display = new JTextField(25); //adding the components to the panel north.add(displayLab); north.add(display); //adding the panel to frame's content pane contentPane.add(north, "north"); } //Declaring the global digits array private void addDigits() { //Add 1 large panel to hold the 3 inner panels JPanel digPanel = new JPanel(); //Set the panel's preferred size so that it will keep everything in line digPanel.setPreferredSize(new Dimension(200, 275)); //Initialize the top 3 digits' JPanel and set its preferrd size JPanel topDigits = new JPanel(); topDigits.setPreferredSize(new Dimension(200,60)); //Initialize the middle 2 digits' JPanel and set its preferred size JPanel midDigits = new JPanel(); midDigits.setPreferredSize(new Dimension(200,60)); //Initialize the bottom digits' JPanel and set its preferred size JPanel botDigits = new JPanel(); botDigits.setPreferredSize(new Dimension(200, 75)); //Initialize the JButton array digits = new JButton[11]; //Initialize each of the top Panel's digit buttons, and add it to the top panel for(int i=1; i