add.java

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.sql.*;
class add extends JFrame{
	Container c;
	JLabel labRno, labName, labCourse, labMarks;
	JTextField txtRno, txtName, txtCourse, txtMarks;
	JButton btnSave,btnBack;

	add(){
		c = getContentPane();
		c.setLayout(new FlowLayout(FlowLayout.CENTER,20,20));
		
		labRno = new JLabel("Enter Rno : ");
		txtRno = new JTextField(10);
		labName = new JLabel("Enter Name : ");
		txtName = new JTextField(10);
		labCourse = new JLabel("Enter Course : ");
		txtCourse = new JTextField(10);
		labMarks = new JLabel("Enter Marks : ");
		txtMarks = new JTextField(10);
		btnSave = new JButton("Add Student");
		btnBack = new JButton("Back to Main");

		Font f = new Font("Times New Roman",Font.BOLD,25);
		labRno.setFont(f);
		txtRno.setFont(f);
		labName.setFont(f);
		txtName.setFont(f);
		labCourse.setFont(f);
		txtCourse.setFont(f);
		labMarks.setFont(f);
		txtMarks.setFont(f);
		btnSave.setFont(f);
		btnBack.setFont(f);
		
		c.add(labRno);
		c.add(txtRno);
		c.add(labName);
		c.add(txtName);
		c.add(labCourse);
		c.add(txtCourse);
		c.add(labMarks);
		c.add(txtMarks);
		c.add(btnSave);
		c.add(btnBack);

		class Eh1 implements ActionListener{
			public void actionPerformed(ActionEvent ae){
				dashboard a = new dashboard();
				dispose();
			}
		}
		btnBack.addActionListener(new Eh1());

		class Eh2 implements ActionListener{
			public void actionPerformed(ActionEvent ae){
				int rno = Integer.parseInt(txtRno.getText());
				String name = txtName.getText();
				int marks = Integer.parseInt(txtMarks.getText());
				String course = txtCourse.getText();

				String user = System.getenv("DB_USER");
				String pwd = System.getenv("DB_PASSWORD");
				String url = "jdbc:mysql://localhost:3306/student_db";
				try{
					DriverManager.registerDriver(new com.mysql.cj.jdbc.Driver());
					try(Connection con = DriverManager.getConnection(url,user,pwd);
					PreparedStatement pst = con.prepareStatement("INSERT INTO student (name, rno, course, marks) VALUES (?, ?, ?, ?)")){
						pst.setString(1,name);
						pst.setInt(2,rno);
						pst.setString(3, course);
        	            			pst.setInt(4, marks);
						pst.executeUpdate();

						JOptionPane.showMessageDialog(c,"Student Saved");

						txtRno.setText("");
						txtName.setText("");
						txtCourse.setText("");
						txtMarks.setText("");
						
						txtRno.requestFocus();
					} catch(SQLException e){
						String msg = "issue " + e;
						JOptionPane.showMessageDialog(c,msg);
					}
				} catch(SQLException e){
					String msg = "issue " + e;
					JOptionPane.showMessageDialog(c,msg);
				}
			}
		}
		btnSave.addActionListener(new Eh2());

		setSize(500,350);
		setLocationRelativeTo(null);
		setTitle("Add Student Details");
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		setVisible(true);
	}
}