Hello I need some assistance in writing a java program THAT
Hello, I need some assistance in writing a java program THAT MUST USE STACKS (LIFO).
Create a Calculator w/ GUI
Write a program that graphically displays a working calculator for simple infix expressions that consist of: single-digit operands, the operators: +, -, *, and /, and parentheses.
Make the following assumptions:
unary operators (e.g. -2) are illegal
all operations, including division, are integer operations (and results are integers)
the input expression contains no embedded spaces and no illegal characters
the input expression is a syntactically correct infix expression
division by zero will not occur (consider how you can remove this restriction)
Create a GUI application, the calculator has a display and a keypad of 20 keys, which are arranged as follows:
C
<
Q
/
7
8
9
*
4
5
6
-
1
2
3
+
0
(
)
=
As the user presses keys to enter an infix expression, the corresponding characters appear in the display. The C (Clear) key erases all input entered so far; the < (Backspace) key erases the last character entered. When the user presses the = key, the expression is evaluated and the result appended to the right end of the expression in the display window. The user can then press C and enter another expression. If the user presses the Q (Quit) key, the calculator ceases operation and is erased from the screen.
| C | < | Q | / |
| 7 | 8 | 9 | * |
| 4 | 5 | 6 | - |
| 1 | 2 | 3 | + |
| 0 | ( | ) | = |
Solution
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
public class Calculator extends JFrame implements ActionListener {
JPanel[] row = new JPanel[5];
JButton[] button = new JButton[19];
String[] buttonString = {\"7\", \"8\", \"9\", \"+\",
\"4\", \"5\", \"6\", \"-\",
\"1\", \"2\", \"3\", \"*\",
\".\", \"/\", \"C\", \"\",
\"+/-\", \"=\", \"0\"};
int[] dimW = {300,45,100,90};
int[] dimH = {35, 40};
Dimension displayDimension = new Dimension(dimW[0], dimH[0]);
Dimension regularDimension = new Dimension(dimW[1], dimH[1]);
Dimension rColumnDimension = new Dimension(dimW[2], dimH[1]);
Dimension zeroButDimension = new Dimension(dimW[3], dimH[1]);
boolean[] function = new boolean[4];
double[] temporary = {0, 0};
JTextArea display = new JTextArea(1,20);
Font font = new Font(\"Times new Roman\", Font.BOLD, 14);
Calculator() {
super(\"Calculator\");
setDesign();
setSize(380, 250);
setResizable(false);
setDefaultCloseOperation(EXIT_ON_CLOSE);
GridLayout grid = new GridLayout(5,5);
setLayout(grid);
for(int i = 0; i < 4; i++)
function[i] = false;
FlowLayout f1 = new FlowLayout(FlowLayout.CENTER);
FlowLayout f2 = new FlowLayout(FlowLayout.CENTER,1,1);
for(int i = 0; i < 5; i++)
row[i] = new JPanel();
row[0].setLayout(f1);
for(int i = 1; i < 5; i++)
row[i].setLayout(f2);
for(int i = 0; i < 19; i++) {
button[i] = new JButton();
button[i].setText(buttonString[i]);
button[i].setFont(font);
button[i].addActionListener(this);
}
display.setFont(font);
display.setEditable(false);
display.setComponentOrientation(ComponentOrientation.RIGHT_TO_LEFT);
display.setPreferredSize(displayDimension);
for(int i = 0; i < 14; i++)
button[i].setPreferredSize(regularDimension);
for(int i = 14; i < 18; i++)
button[i].setPreferredSize(rColumnDimension);
button[18].setPreferredSize(zeroButDimension);
row[0].add(display);
add(row[0]);
for(int i = 0; i < 4; i++)
row[1].add(button[i]);
row[1].add(button[14]);
add(row[1]);
for(int i = 4; i < 8; i++)
row[2].add(button[i]);
row[2].add(button[15]);
add(row[2]);
for(int i = 8; i < 12; i++)
row[3].add(button[i]);
row[3].add(button[16]);
add(row[3]);
row[4].add(button[18]);
for(int i = 12; i < 14; i++)
row[4].add(button[i]);
row[4].add(button[17]);
add(row[4]);
setVisible(true);
}
public void clear() {
try {
display.setText(\"\");
for(int i = 0; i < 4; i++)
function[i] = false;
for(int i = 0; i < 2; i++)
temporary[i] = 0;
} catch(NullPointerException e) {
}
}
public void getSqrt() {
try {
double value = Math.sqrt(Double.parseDouble(display.getText()));
display.setText(Double.toString(value));
} catch(NumberFormatException e) {
}
}
public void getPosNeg() {
try {
double value = Double.parseDouble(display.getText());
if(value != 0) {
value = value * (-1);
display.setText(Double.toString(value));
}
else {
}
} catch(NumberFormatException e) {
}
}
public void getResult() {
double result = 0;
temporary[1] = Double.parseDouble(display.getText());
String temp0 = Double.toString(temporary[0]);
String temp1 = Double.toString(temporary[1]);
try {
if(temp0.contains(\"-\")) {
String[] temp00 = temp0.split(\"-\", 2);
temporary[0] = (Double.parseDouble(temp00[1]) * -1);
}
if(temp1.contains(\"-\")) {
String[] temp11 = temp1.split(\"-\", 2);
temporary[1] = (Double.parseDouble(temp11[1]) * -1);
}
} catch(ArrayIndexOutOfBoundsException e) {
}
try {
if(function[2] == true)
result = temporary[0] * temporary[1];
else if(function[3] == true)
result = temporary[0] / temporary[1];
else if(function[0] == true)
result = temporary[0] + temporary[1];
else if(function[1] == true)
result = temporary[0] - temporary[1];
display.setText(Double.toString(result));
for(int i = 0; i < 4; i++)
function[i] = false;
} catch(NumberFormatException e) {
}
}
public final void setDesign() {
try {
UIManager.setLookAndFeel(
\"com.sun.java.swing.plaf.nimbus.NimbusLookAndFeel\");
} catch(Exception e) {
}
}
@Override
public void actionPerformed(ActionEvent ae) {
if(ae.getSource() == button[0])
display.append(\"7\");
if(ae.getSource() == button[1])
display.append(\"8\");
if(ae.getSource() == button[2])
display.append(\"9\");
if(ae.getSource() == button[3]) {
//add function[0]
temporary[0] = Double.parseDouble(display.getText());
function[0] = true;
display.setText(\"\");
}
if(ae.getSource() == button[4])
display.append(\"4\");
if(ae.getSource() == button[5])
display.append(\"5\");
if(ae.getSource() == button[6])
display.append(\"6\");
if(ae.getSource() == button[7]) {
//subtract function[1]
temporary[0] = Double.parseDouble(display.getText());
function[1] = true;
display.setText(\"\");
}
if(ae.getSource() == button[8])
display.append(\"1\");
if(ae.getSource() == button[9])
display.append(\"2\");
if(ae.getSource() == button[10])
display.append(\"3\");
if(ae.getSource() == button[11]) {
//multiply function[2]
temporary[0] = Double.parseDouble(display.getText());
function[2] = true;
display.setText(\"\");
}
if(ae.getSource() == button[12])
display.append(\".\");
if(ae.getSource() == button[13]) {
//divide function[3]
temporary[0] = Double.parseDouble(display.getText());
function[3] = true;
display.setText(\"\");
}
if(ae.getSource() == button[14])
clear();
if(ae.getSource() == button[15])
getSqrt();
if(ae.getSource() == button[16])
getPosNeg();
if(ae.getSource() == button[17])
getResult();
if(ae.getSource() == button[18])
display.append(\"0\");
}
public static void main(String[] arguments) {
Calculator c = new Calculator();
}
}
//the gui has close button so I didn\'t code that and < button has not been coded since the use of C button..... thankyou




