ListOfLessons.java

import javax.swing.*;
import javax.swing.table.DefaultTableModel;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

public class ListOfLessons extends javax.swing.JFrame {

    Connection con= null;
    PreparedStatement pst =null;
    ResultSet rs= null;
    public ListOfLessons() {
        initComponents();
         con=(Connection) operators.connect();
    }

    
    
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">//GEN-BEGIN:initComponents
    private void initComponents() {

        jScrollPane1 = new javax.swing.JScrollPane();
        jTable1 = new javax.swing.JTable();
        jButton2 = new javax.swing.JButton();
        jButton3 = new javax.swing.JButton();
        jButton4 = new javax.swing.JButton();
        jButton5 = new javax.swing.JButton();
        jButton6 = new javax.swing.JButton();
        jButton1 = new javax.swing.JButton();
        jLabel1 = new javax.swing.JLabel();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

        jTable1.setModel(new javax.swing.table.DefaultTableModel(
            new Object [][] {
                {null, null, null},
                {null, null, null},
                {null, null, null},
                {null, null, null}
            },
            new String [] {
                "LessonID", "LessonName", "NumberOfStudent"
            }
        ));
        jScrollPane1.setViewportView(jTable1);

        jButton2.setText("List Of Students");
        jButton2.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton2ActionPerformed(evt);
            }
        });

        jButton3.setText("Remove Student");
        jButton3.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton3ActionPerformed(evt);
            }
        });

        jButton4.setText("List Of Lessons");
        jButton4.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton4ActionPerformed(evt);
            }
        });

        jButton5.setText("Add Exam");
        jButton5.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton5ActionPerformed(evt);
            }
        });

        jButton6.setText("Update Grade");
        jButton6.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton6ActionPerformed(evt);
            }
        });

        jButton1.setText("Show");
        jButton1.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton1ActionPerformed(evt);
            }
        });

        jLabel1.setFont(new java.awt.Font("Dialog", 1, 36)); // NOI18N
        jLabel1.setForeground(new java.awt.Color(0, 153, 255));
        jLabel1.setText("List of Lessons");

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addGroup(layout.createSequentialGroup()
                        .addContainerGap()
                        .addComponent(jButton2)
                        .addGap(18, 18, 18)
                        .addComponent(jButton4)
                        .addGap(18, 18, 18)
                        .addComponent(jButton6)
                        .addGap(18, 18, 18)
                        .addComponent(jButton5)
                        .addGap(18, 18, 18)
                        .addComponent(jButton3))
                    .addGroup(layout.createSequentialGroup()
                        .addGap(54, 54, 54)
                        .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                            .addComponent(jLabel1)
                            .addGroup(layout.createSequentialGroup()
                                .addComponent(jButton1)
                                .addGap(33, 33, 33)
                                .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 422, javax.swing.GroupLayout.PREFERRED_SIZE)))))
                .addContainerGap(7, Short.MAX_VALUE))
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addContainerGap()
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(jButton2)
                    .addComponent(jButton3)
                    .addComponent(jButton4)
                    .addComponent(jButton5)
                    .addComponent(jButton6))
                .addGap(40, 40, 40)
                .addComponent(jLabel1)
                .addGap(32, 32, 32)
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 335, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addComponent(jButton1))
                .addContainerGap(30, Short.MAX_VALUE))
        );

        pack();
    }// </editor-fold>//GEN-END:initComponents

    private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_jButton2ActionPerformed
        // TODO add your handling code here:
        new ListOfStudent().setVisible(true);
        this.setVisible(false);
        
    }//GEN-LAST:event_jButton2ActionPerformed

    private void jButton3ActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_jButton3ActionPerformed
        // TODO add your handling code here:
        new RemoveStudent().setVisible(true);
        this.setVisible(false);
    }//GEN-LAST:event_jButton3ActionPerformed

    private void jButton4ActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_jButton4ActionPerformed
        // TODO add your handling code here:
        new ListOfLessons().setVisible(true);
        this.setVisible(false);
    }//GEN-LAST:event_jButton4ActionPerformed

    private void jButton5ActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_jButton5ActionPerformed
        // TODO add your handling code here:
        new AddExam().setVisible(true);
        this.setVisible(false);
    }//GEN-LAST:event_jButton5ActionPerformed

    private void jButton6ActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_jButton6ActionPerformed
        // TODO add your handling code here:
        new UpdateGrade().setVisible(true);
        this.setVisible(false);
    }//GEN-LAST:event_jButton6ActionPerformed

    private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_jButton1ActionPerformed
        // TODO add your handling code here:
         try{
          
            PreparedStatement pst =con.prepareCall("SELECT l.lessonID, l.lessonName, COUNT(s.studentID) AS numberOfStudent FROM student s, lessonenrollment le, lesson l WHERE l.lessonID = le.FK3_lessonID AND le.FK2_studentID = s.studentID");
            ResultSet rs = pst.executeQuery();
            DefaultTableModel tm = (DefaultTableModel)jTable1.getModel();
            tm.setRowCount(0);
            
            while(rs.next()){
                Object o[] = {rs.getInt("lessonID"),rs.getString("lessonName"),rs.getString("numberOfStudent")};
                tm.addRow(o);
                
            }
            //JOptionPane.showMessageDialog(rootPane, "");
        } catch(Exception e){
            JOptionPane.showMessageDialog(rootPane, e);
        }
        
    }//GEN-LAST:event_jButton1ActionPerformed

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        /* Set the Nimbus look and feel */
        //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
        /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
         * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html 
         */
        try {
            for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
                if ("Nimbus".equals(info.getName())) {
                    javax.swing.UIManager.setLookAndFeel(info.getClassName());
                    break;
                }
            }
        } catch (ClassNotFoundException ex) {
            java.util.logging.Logger.getLogger(ListOfLessons.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(ListOfLessons.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(ListOfLessons.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(ListOfLessons.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        }
        //</editor-fold>

        /* Create and display the form */
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new ListOfLessons().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify//GEN-BEGIN:variables
    private javax.swing.JButton jButton1;
    private javax.swing.JButton jButton2;
    private javax.swing.JButton jButton3;
    private javax.swing.JButton jButton4;
    private javax.swing.JButton jButton5;
    private javax.swing.JButton jButton6;
    private javax.swing.JLabel jLabel1;
    private javax.swing.JScrollPane jScrollPane1;
    private javax.swing.JTable jTable1;
    // End of variables declaration//GEN-END:variables
}