The following is an example code for a simple Java GUI calculator: ```java import java.awt.*; import java.awt.event.*; import javax.swing.*; public class CalculatorGUI extends JFrame implements ActionListener { private JPanel panel; private JTextField textField; private JButton[] buttons; private String[] buttonLabels = { \t"7", "8", "9", "/", \t"4", "5", "6", "*", \t"1", "2", "3", "-", \t"0", ".", "=", "+" }; private String currentInput = ""; private double result = 0; private String operator = ""; public CalculatorGUI() { panel = new JPanel(); panel.setLayout(new GridLayout(4, 4)); textField = new JTextField(); textField.setEditable(false); buttons = new JButton[buttonLabels.length]; for (int i = 0; i < buttonLabels.length; i++) { buttons[i] = new JButton(buttonLabels[i]); buttons[i].addActionListener(this); panel.add(buttons[i]); } add(textField, BorderLayout.NORTH); add(panel, BorderLayout.CENTER); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setTitle("Calculator"); setSize(300, 400); setLocationRelativeTo(null); setVisible(true); } public void actionPerformed(ActionEvent e) { String command = e.getActionCommand(); switch (command) { case "0": case "1": case "2": case "3": case "4": case "5": case "6": case "7": case "8": case "9": currentInput += command; textField.setText(currentInput); break; case ".": if (!currentInput.contains(".")) { currentInput += "."; } textField.setText(currentInput); break; case "/": case "*": case "-": case "+": operator = command; result = Double.parseDouble(currentInput); currentInput = ""; textField.setText(""); break; case "=": double secondOperand = Double.parseDouble(currentInput); switch (operator) { case "/": result /= secondOperand; break; case "*": result *= secondOperand; break; case "-": result -= secondOperand; break; case "+": result += secondOperand; break; } currentInput = String.valueOf(result); textField.setText(currentInput); break; default: break; } } public static void main(String[] args) { SwingUtilities.invokeLater(new Runnable() { public void run() { new CalculatorGUI(); } }); } } ``` You can instantiate the calculator GUI by creating a CalculatorGUI object and use the 'SwingUtilities. invokeLater()' method to launch the application in the event distribution thread.

The following is an example code for developing a clock using a Java GUI: ```java import javax.swing.*; import java.awt.*; import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Date; public class Clock extends JFrame { private JLabel timeLabel; public static void main(String[] args) { SwingUtilities.invokeLater(() -> { Clock clock = new Clock(); clock.setVisible(true); }); } public Clock() { setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setTitle("Clock"); setSize(300, 200); setLocationRelativeTo(null); timeLabel = new JLabel(); timeLabel.setFont(new Font("Arial", Font.BOLD, 40)); timeLabel.setHorizontalAlignment(SwingConstants.CENTER); updateTime(); Timer timer = new Timer(1000, e -> updateTime()); timer.start(); getContentPane().add(timeLabel); } private void updateTime() { Date currentTime = Calendar.getInstance().getTime(); SimpleDateFormat dateFormat = new SimpleDateFormat("HH:mm:ss"); String timeText = dateFormat.format(currentTime); timeLabel.setText(timeText); } } ``` This example code creates a 'Clock' class that inherits from 'JFrame'. In the constructor, some basic properties of the window were set and a 'JLabel' was created to display the time. Then, use the 'Timer' class to update the time every second` The updateTime() method uses' SimpleDateFormat 'to format the current time as a string of' HH: mm: ss', and then sets it to the text of 'timeLabel'. Finally, add 'timeLabel' to the content panel of the window. To compile and run this code, you need to install the Java Development Kit (JDK) and save the code as a file called 'Clock. java'. Then, compile the code using 'Javac Clock. java' in the command line window, and then run the program using 'Java Clock'.

The following is a basic example of developing code for a form using a Java GUI: ```java import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JPanel; import javax.swing.JTextField; public class FormExample { public static void main(String[] args) { //Create a JFrame object as a window container JFrame frame=new JFrame ("form"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //Create a JPanel object as the main panel JPanel panel = new JPanel(); //Create various components of the form JLabel nameLabel=new JLabel ("Name:"); JTextField nameField = new JTextField(20); JLabel ageLabel=new JLabel ("Age:"); JTextField ageField = new JTextField(3); JButton submitButton=new JButton ("submit"); //Add components to the panel panel.add(nameLabel); panel.add(nameField); panel.add(ageLabel); panel.add(ageField); panel.add(submitButton); //Add panel to window frame.getContentPane().add(panel); //Set window size and display frame.setSize(300, 200); frame.setVisible(true); } } ``` This is a simple form example, including name, age, and submit button. You can add more components and functions as needed. Running this code will display a window containing the form, where users can enter their name and age, and click the submit button to proceed.