This is my Java Code for the arithmetic calculator :

import javax.swing.$*$;

import java.awt.$*$;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

public class Calculator extends JFrame implements ActionListener $\{$

private JTextField display;

private StringBuilder currentInput;

public Calculator$()\{$

currentInput $=$ new StringBuilder$()$;

display $=$ new JTextField$()$;

display.setEditable$($false$)$;

display.setHorizontalAlignment$($JTextField$.$RIGHT$)$;

JPanel panel $=$ new JPanel$()$;

panel.setLayout$($new GridLayout$(4,4))$;

String$[]$ buttons $=\{$

$"7","8","9","/",$

$"4","5","6","*",$

$"1","2","3","-",$

$"0","$C$","=","+"$

$\}$;

for $($String text : buttons$)\{$

JButton button $=$ new JButton$($text$)$;

button.addActionListener$($this$)$;

panel.add$($button$)$;

$\}$

setLayout$($new BorderLayout$())$;

add$($display$,$ BorderLayout.NORTH$)$;

add$($panel$,$ BorderLayout.CENTER$)$;

setTitle$("$Calculator$")$;

setSize$(300,400)$;

setDefaultCloseOperation$($JFrame$.$EXIT$\_$ON$\_$CLOSE$)$;

setVisible$($true$)$;

$\}$

@Override

public void actionPerformed$($ActionEvent e$)\{$

String command $=$ e$.$getActionCommand$()$;

if $($command$.$charAt$(0)==\text{'}$C$\text{'})\{$

currentInput.setLength$(0)$;

display.setText$("")$;

$\}$ else if $($command$.$charAt$(0)==\text{'}=\text{'})\{$

try $\{$

double result $=$ evaluate$($currentInput$.$toString$())$;

display.setText$($Double$.$toString$($result$))$;

currentInput.setLength$(0)$;

$\}$ catch $($Exception ex$)\{$

display.setText$("$Error$")$;

currentInput.setLength$(0)$;

$\}$

$\}$ else $\{$

currentInput.append$($command$)$;

display.setText$($currentInput$.$toString$())$;

$\}$

$\}$

private double evaluate$($String expression$)\{$

$//$ Simple evaluation logic $($not robust for complex expressions$)$

return new ScriptEngineManager$().$getEngineByName$("$JavaScript$").$eval$($expression$)$;

$\}$

public static void main$($String$[]$ args$)\{$

new Calculator$()$;

$\}$

$\}$

$----->$using this java code:

$1.$Calculate Halstead Metrics for the program and explain it means.

$2.$Calculate McCabe Cyclomatic Complexity and explain it means.

$3.$Calculate the Henry$-$Kafura metric and explain what it means.

$4.$Calculate the Card and Class metric and explain what it means.

$5.$Calculate the Chidamber and Kemerer metric and explain what it means