JAVA & MySQL Code - Ordering JTable Data In Java NetBeans

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In this java Tutorial we will learn How To Sort JTable Data Ascending And Descending By Column Name ('age' in this example) With Java NetBeans And MySQL Database .
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Project Source Code:
// Create Class User
package JAVA_VIDEOS_TUTORIALS;

public class User {
    
    private int id;
    private String fname;
    private String lname;
    private int age;
    
    
    public User(int Id,String Fname,String Lname,int Age)
    {
        this.id = Id;
        this.fname = Fname;
        this.lname = Lname;
        this.age = Age;
    }
    
    public int getId()
    {
        return id;
    }
    
    public String getFname()
    {
        return fname;
    }
    
    public String getLname()
    {
        return lname;
    }
    
    public int getAge()
    {
        return age;
    }
}

// Creates new form Java_JTable_Order
package JAVA_VIDEOS_TUTORIALS;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import java.util.ArrayList;
import javax.swing.table.DefaultTableModel;

public class Java_JTable_Order extends javax.swing.JFrame {

    /**
     * Creates new form Java_JTable_Order
     */
    public Java_JTable_Order() {
        initComponents();

        showUsersInJTable(query);
    }

    String query = "SELECT * FROM users";
    
    // function to get the connection
    public Connection getConnection()
    {
        Connection con = null;
        try
        {
          con = DriverManager.getConnection("jdbc:mysql://localhost/test_db","root",""); 
        }catch(Exception ex)
        {
            System.out.println(ex.getMessage());
        }
        return con;
    }
    
    // function return an arraylist of users
    public ArrayList<User> ListUsers(String query)
    {
        ArrayList<User> usersList = new ArrayList<User>();
        Connection con = getConnection();
        Statement st;
        ResultSet rs;
        try{
            st = con.createStatement();
            rs = st.executeQuery(query);
            User user;
            while(rs.next())
            {
                user = new User(
                              rs.getInt("id"),
                              rs.getString("fname"),
                              rs.getString("lname"),
                              rs.getInt("age")
                               );
                usersList.add(user);
            }
        }catch(Exception ex)
        {
            System.out.println(ex.getMessage());
        }
        
        return usersList;
        
    }
    
    
    // function to display the result in jtable
    public void showUsersInJTable(String OrderQuery)
    {
        ArrayList<User> users = ListUsers(OrderQuery);
        DefaultTableModel model = new DefaultTableModel();
        model.setColumnIdentifiers(new Object[]{"ID","First Name","Last Name","Age"});
        Object[] row = new Object[4];
        
        for(int i = 0; i < users.size(); i++)
        {
            row[0] = users.get(i).getId();
            row[1] = users.get(i).getFname();
            row[2] = users.get(i).getLname();
            row[3] = users.get(i).getAge();
            
            model.addRow(row);
        }
        
        jTable_Order.setModel(model);
    }
    
    
    
    
    
    /**
     * This method is called from within the constructor to initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is always
     * regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
    private void initComponents() {

        jButton_ASC = new javax.swing.JButton();
        jButton_DESC = new javax.swing.JButton();
        jScrollPane1 = new javax.swing.JScrollPane();
        jTable_Order = new javax.swing.JTable();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

        jButton_ASC.setText("ASCENDING");
        jButton_ASC.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton_ASCActionPerformed(evt);
            }
        });

        jButton_DESC.setText("DESCENDING");
        jButton_DESC.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jButton_DESCActionPerformed(evt);
            }
        });

        jTable_Order.setModel(new javax.swing.table.DefaultTableModel(
            new Object [][] {
                {null, null, null, null},
                {null, null, null, null},
                {null, null, null, null},
                {null, null, null, null}
            },
            new String [] {
                "Title 1", "Title 2", "Title 3", "Title 4"
            }
        ));
        jScrollPane1.setViewportView(jTable_Order);

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addComponent(jButton_ASC)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                .addComponent(jButton_DESC))
            .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addContainerGap())
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(jButton_ASC)
                    .addComponent(jButton_DESC))
                .addGap(27, 27, 27)
                .addComponent(jScrollPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 459, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addGap(0, 17, Short.MAX_VALUE))
        );

        pack();
    }// </editor-fold>                        

// button ascending
 private void jButton_ASCActionPerformed(java.awt.event.ActionEvent evt)
 {                                            
        // TODO add your handling code here:
        
        query = "SELECT * FROM users ORDER BY age ASC";
        showUsersInJTable(query);
    }                                           

// button descending
  private void jButton_DESCActionPerformed(java.awt.event.ActionEvent evt) {                                             
        // TODO add your handling code here:
        query = "SELECT * FROM users ORDER BY age DESC";
        showUsersInJTable(query);
 }                                            

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        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(Java_JTable_Order.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (InstantiationException ex) {
            java.util.logging.Logger.getLogger(Java_JTable_Order.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (IllegalAccessException ex) {
            java.util.logging.Logger.getLogger(Java_JTable_Order.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
        } catch (javax.swing.UnsupportedLookAndFeelException ex) {
            java.util.logging.Logger.getLogger(Java_JTable_Order.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 Java_JTable_Order().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify                     
    private javax.swing.JButton jButton_ASC;
    private javax.swing.JButton jButton_DESC;
    private javax.swing.JScrollPane jScrollPane1;
    private javax.swing.JTable jTable_Order;
    // End of variables declaration                   
}
// OUTPUT:


jtable default order



jtable ascending order




jtable ascending order