Swing student registration form

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.Locale;

public class Main {

javax.swing supplies buttons, labels, panels and frames. java.awt supplies layouts, colours and fonts. java.awt.event supplies listener/event types. Locale is available where text formatting needs it. Main matches the source filename.

    static JPanel root(String title) {
        for(String key:new String[]{"Label.font","Button.font","RadioButton.font","CheckBox.font","TextField.font","TextArea.font","ComboBox.font"})UIManager.put(key,new Font(Font.SANS_SERIF,Font.PLAIN,18));

root configures the selected UIManager font keys to an 18-point sans-serif font before creating the form’s components. This affects the Java application, not the website’s CSS.

        JPanel panel=new JPanel(new BorderLayout(12,12));panel.setBorder(BorderFactory.createEmptyBorder(20,20,20,20));
        JLabel heading=new JLabel(title);heading.setFont(new Font(Font.SANS_SERIF,Font.BOLD,24));panel.add(heading,BorderLayout.NORTH);return panel;
    }

BorderLayout places the heading in NORTH and leaves CENTER for each experiment’s form. The empty border adds padding; the heading uses a larger bold font. Return the JPanel for further assembly.

    static void show(String title,JPanel panel) {
        JFrame frame=new JFrame(title);frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);frame.setContentPane(panel);frame.pack();frame.setLocationRelativeTo(null);frame.setVisible(true);
    }

show creates a JFrame, installs its content, packs it to component sizes, centres it and makes it visible. EXIT_ON_CLOSE ends this demonstration application when its window closes. The desktop main calls this helper on the event-dispatch thread.

    public static JPanel createPanel(){
        JPanel panel=root("Student Registration"),form=new JPanel(new GridLayout(0,2,10,10));
        String[] labels={"Name","Email","Contact","Address"};JTextField[] fields=new JTextField[4];
        for(int i=0;i<4;i++){form.add(new JLabel(labels[i]));fields[i]=new JTextField(25);fields[i].setName(labels[i].toLowerCase(Locale.ROOT));form.add(fields[i]);}

GridLayout pairs labels and fields for name, email, contact and address. Each field gets a stable component name. The array keeps references so validation and reset can visit all fields.

        JComboBox<String> gender=new JComboBox<>(new String[]{"Select gender","Male","Female","Other"});gender.setName("gender");form.add(new JLabel("Gender"));form.add(gender);
        JPanel courses=new JPanel(new GridLayout(2,2));JCheckBox[] choices=new JCheckBox[4];String[] names={"Java","Python","Data Science","AI"};
        for(int i=0;i<4;i++){choices[i]=new JCheckBox(names[i]);courses.add(choices[i]);}form.add(new JLabel("Courses"));form.add(courses);

The initial combo item is a prompt rather than a valid selection. Four checkboxes allow more than one course, unlike radio buttons in a group.

        JRadioButton online=new JRadioButton("Online"),offline=new JRadioButton("Offline");ButtonGroup mode=new ButtonGroup();mode.add(online);mode.add(offline);JPanel modes=new JPanel();modes.add(online);modes.add(offline);form.add(new JLabel("Mode"));form.add(modes);

Online and Offline share one ButtonGroup, allowing at most one selected mode. Put the actual components in a visible panel as well as in the logical group.

        JTextArea output=new JTextArea(5,42);output.setName("summary");output.setEditable(false);output.setLineWrap(true);output.setWrapStyleWord(true);
        JPanel center=new JPanel(new BorderLayout(10,10));center.add(form,BorderLayout.NORTH);center.add(new JScrollPane(output),BorderLayout.CENTER);panel.add(center,BorderLayout.CENTER);
        JButton submit=new JButton("Submit"),reset=new JButton("Reset"),exit=new JButton("Exit");JPanel buttons=new JPanel();buttons.add(submit);buttons.add(reset);buttons.add(exit);panel.add(buttons,BorderLayout.SOUTH);

The output is read-only and scrollable. BorderLayout separates form, summary and bottom buttons. Submit, Reset and Exit will receive their own callbacks.

        submit.addActionListener(e->{
            for(JTextField field:fields)if(field.getText().trim().isEmpty()){output.setText("Complete all text fields.");return;}
            if(!fields[1].getText().trim().matches("[^\\s@]+@[^\\s@]+\\.[^\\s@]+")){output.setText("Enter a valid email format.");return;}
            if(!fields[2].getText().trim().matches("[0-9]{10}")){output.setText("Contact must contain 10 digits.");return;}

On Submit, reject blank fields, an email that fails the example format pattern and a contact number that is not exactly ten digits. Each failure displays a message and returns from this event handler.

            StringBuilder selected=new StringBuilder();for(JCheckBox choice:choices)if(choice.isSelected()){if(selected.length()>0)selected.append(", ");selected.append(choice.getText());}
            if(gender.getSelectedIndex()==0||mode.getSelection()==null||selected.length()==0){output.setText("Select gender, at least one course and a learning mode.");return;}
            output.setText("Registered: "+fields[0].getText().trim()+"\nEmail: "+fields[1].getText().trim()+"\nContact: "+fields[2].getText().trim()+"\nAddress: "+fields[3].getText().trim()+"\nGender: "+gender.getSelectedItem()+"\nCourses: "+selected+"\nMode: "+(online.isSelected()?"Online":"Offline"));
        });

Build a comma-separated course list. Require a non-prompt gender, a learning-mode selection and at least one course. Then display the collected form values. The validation checks format; it does not verify that an email account or phone number exists.

        reset.addActionListener(e->{for(JTextField field:fields)field.setText("");gender.setSelectedIndex(0);for(JCheckBox choice:choices)choice.setSelected(false);mode.clearSelection();output.setText("");});
        exit.addActionListener(e->{Window window=SwingUtilities.getWindowAncestor(panel);if(window!=null)window.dispose();});return panel;
    }

Reset clears text, selections and summary. Exit finds the panel’s enclosing Window and disposes it if present. Return the assembled panel after registering the handlers.

    public static void main(String[] args){SwingUtilities.invokeLater(()->show("Student Registration",createPanel()));}

}

SwingUtilities.invokeLater schedules the lambda on Swing’s event-dispatch thread. The lambda creates the panel and calls show. This main needs a graphical desktop; the panel and its event handlers are separate from console input.