import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class Circle extends JFrame {
// declare variables
private double radius = 0, circ = 0, diameter = 0, area = 0, distance = 0;
private double X1, X2, Y1, Y2;
private ButtonHandler buttonHandler;
// declare GUI components
JLabel lX1, lX2, lY1, lY2, lWelcome, lRadius, lCirc, lDiameter, lArea;
JTextField tX1, tX2, tY1, tY2, tRadius, tCirc, tDiameter, tArea;
JButton bReset, bCompute;
Container c;
JPanel pCenter;
//set and get methods
public double distance (double X1, double X2, double Y1, double Y2)
{
distance = Math.sqrt((X2 - X1) * (X2 - X1) + (Y2 - Y1) * (Y2 - Y1));
return distance;
}
public double radius (double X1, double Y1, double X2, double Y2)
{
return distance(X1, Y1, X2, Y2);
}
public double circ (double radius)
{
circ = 2*Math.PI * radius;
return circ;
}
public double area (double radius)
{
area = Math.PI * radius * radius;
return area;
}
{
//create GUI components
lX1 = new JLabel("Enter X1:");
lX2 = new JLabel("Enter X2:");
lY1 = new JLabel("Enter Y1:");
lY2 = new JLabel("Enter Y2:");
lRadius = new JLabel("Radius =");
lCirc = new JLabel("Circumference =");
lDiameter = new JLabel("Diameter =");
lArea = new JLabel("Area =");
lWelcome = new JLabel("Circle", SwingConstants.CENTER);
tX1 = new JTextField("");
tX2 = new JTextField("");
tY1 = new JTextField("");
tY2 = new JTextField("");
tRadius = new JTextField("");
tCirc = new JTextField("");
tDiameter = new JTextField("");
tArea = new JTextField("");
tX1.setEditable(true);
tX2.setEditable(true);
tY1.setEditable(true);
tY2.setEditable(true);
tRadius.setEditable(false);
tCirc.setEditable(false);
tDiameter.setEditable(false);
tArea.setEditable(false);
bReset = new JButton("Reset");
bCompute = new JButton("Compute");
c = getContentPane();
pCenter = new JPanel();
}
public Circle() {
//add GUI components
pCenter.setLayout(new GridLayout(9,2));
pCenter.add(lX1);
pCenter.add(tX1);
pCenter.add(lX2);
pCenter.add(tX2);
pCenter.add(lY1);
pCenter.add(tY1);
pCenter.add(lY2);
pCenter.add(tY2);
pCenter.add(lRadius);
pCenter.add(tRadius);
pCenter.add(lCirc);
pCenter.add(tCirc);
pCenter.add(lDiameter);
pCenter.add(tDiameter);
pCenter.add(lArea);
pCenter.add(tArea);
pCenter.add(bReset);
pCenter.add(bCompute);
c.setLayout(new BorderLayout());
c.add(lWelcome, BorderLayout.NORTH);
c.add(pCenter, BorderLayout.CENTER);
//register with buttons
buttonHandler = new ButtonHandler();
bReset.addActionListener(buttonHandler);
bCompute.addActionListener(buttonHandler);
//render the window
setTitle("Circle Info");
setSize(500, 300);
setLocation(100, 100);
setResizable(false);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);
}
private class ButtonHandler implements ActionListener {
public void actionPerformed(ActionEvent ae) {
if (ae.getSource().equals(bReset)) {
tX1.setText("");
tX2.setText("");
tY1.setText("");
tY2.setText("");
tRadius.setText("");
tCirc.setText("");
tDiameter.setText("");
tArea.setText("");
}
else {
try {
X1 = Double.parseDouble(tX1.getText());
X2 = Double.parseDouble(tX2.getText());
Y1 = Double.parseDouble(tY1.getText());
Y2 = Double.parseDouble(tY2.getText());
radius = Double.parseDouble(tRadius.getText());
circ = Double.parseDouble(tCirc.getText());
diameter = Double.parseDouble(tDiameter.getText());
area = Double.parseDouble(tArea.getText());
}
catch (Exception e) {
JOptionPane.showMessageDialog(null, "Invalid input, please try again");
return;
}
}
}
}
public static void main(String[] args) {
Circle myApp = new Circle();
}
}