The "Next" is not working

[Yohan Weerasinghe]

Hi,

Please have a look at the following set of codes.

JustTest.java

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

public class JustTest extends JFrame
{
    private JLabel idLabel, nameLabel, phoneLabel, addressLabel;
    private JTextField idTxt, nameTxt, phoneTxt, addressTxt;
    private JButton first,last,next,previous;
    private FlowLayout flow;
    private GridLayout grid;
    private JPanel centerPanel, southPanel;
    
    JustTestSQL jts = new JustTestSQL();
    
    public JustTest()
    {
        idLabel = new JLabel("ID:");
        nameLabel = new JLabel("Name:");
        addressLabel = new JLabel("Address:");
        phoneLabel = new JLabel("Phone:");
        
        idTxt = new JTextField(10);
        nameTxt = new JTextField(10);
        addressTxt = new JTextField(10);
        phoneTxt = new JTextField(10);
        
        first = new JButton("First");
        first.addActionListener(new FirstButton());
        
        last = new JButton("Last");
        last.addActionListener(new LastButton());
        
        next = new JButton("Next");
        next.addActionListener(new NextButton());
        
        previous = new JButton("Previous");
        previous.addActionListener(new PreviousButton());
        
        flow = new FlowLayout();
        southPanel = new JPanel();
        southPanel.setLayout(flow);
        southPanel.add(first);
        southPanel.add(last);
        southPanel.add(next);
        southPanel.add(previous);
        
        grid = new GridLayout(4,2,1,1);
        centerPanel = new JPanel();
        centerPanel.setLayout(grid);
        
        centerPanel.add(idLabel);
        centerPanel.add(idTxt);
        centerPanel.add(nameLabel);
        centerPanel.add(nameTxt);
        centerPanel.add(addressLabel);
        centerPanel.add(addressTxt);
        centerPanel.add(phoneLabel);
        centerPanel.add(phoneTxt);
        
        getContentPane().add(centerPanel,"Center");
        getContentPane().add(southPanel,"South");       
        
        
        
    }
    
    private void buttonStatus()
    {
        try
        {
            if(jts.getFirstStatus())
            {
                first.setEnabled(false);
                previous.setEnabled(false);                
               
             }
           else if(jts.getLastStatus())
             {
                 last.setEnabled(false);
                 next.setEnabled(false);
                 
                 first.setEnabled(true);
                 previous.setEnabled(true);
            
             }
           else if(jts.getFirstStatus()!=true || jts.getLastStatus()!=true)
           {
               first.setEnabled(true);
               last.setEnabled(true);
               next.setEnabled(true);
               previous.setEnabled(true);
           }
        }
        catch(Exception e)
        {
            
        }
    }
    
    private class FirstButton implements ActionListener
    {
        public void actionPerformed(ActionEvent ae)
        {
            if(ae.getSource().equals(first))
            {
                buttonStatus();
                jts.first();
                idTxt.setText(jts.getID());
                nameTxt.setText(jts.getName());
                addressTxt.setText(jts.getAddress());
                phoneTxt.setText(jts.getPhone());
                
            }
        }
    }
    
    private class LastButton implements ActionListener
    {
        public void actionPerformed(ActionEvent ae)
        {
                buttonStatus();
                jts.last();
                idTxt.setText(jts.getID());
                nameTxt.setText(jts.getName());
                addressTxt.setText(jts.getAddress());
                phoneTxt.setText(jts.getPhone());
               
        }
    }
    
    private class NextButton implements ActionListener
    {
        public void actionPerformed(ActionEvent ae)
        {
                buttonStatus();
                jts.next();
                idTxt.setText(jts.getID());
                nameTxt.setText(jts.getName());
                addressTxt.setText(jts.getAddress());
                phoneTxt.setText(jts.getPhone());
               
        }
    }
    
    private class PreviousButton implements ActionListener
    {
        public void actionPerformed(ActionEvent ae)
        {
                buttonStatus();
                jts.previous();
                idTxt.setText(jts.getID());
                nameTxt.setText(jts.getName());
                addressTxt.setText(jts.getAddress());
                phoneTxt.setText(jts.getPhone());
                
        }
    }
    
    public static void main(String[]args)
    {
        try
        {
            UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
        }
        catch(Exception e)
        {
            JOptionPane.showMessageDialog(null, "GUI Error: "+e);
        }
        JustTest jt = new JustTest();
        jt.setVisible(true);
        jt.setSize(500,200);
        jt.validate();
        jt.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }
}

JustTestSQL.java

import java.sql.*;
import java.awt.*;
import javax.swing.JOptionPane;

public class JustTestSQL
{
    private Connection con;
    private Statement st;
    private ResultSet rs;
    private String str;
    private boolean temp;
    
    public JustTestSQL()
    {
        try
        {
            Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
            con = DriverManager.getConnection("jdbc:odbc:Employee","sa","sasasa");
            st = con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDATABLE);
            rs = st.executeQuery("select * from Customer");
        }
        catch(Exception e)
        {
            JOptionPane.showMessageDialog(null, "Error: "+e);
        }
    }
    
    public void first()
    {  
        try
        {
            rs.first();
        }
        catch(Exception e)
        {
           JOptionPane.showMessageDialog(null, "Error: "+e);
        }
    }
    
    public void last()
    {
        try
        {
            rs.last();
        }
        catch(Exception e)
        {
            JOptionPane.showMessageDialog(null, "Error: "+e);
        }
    }
    
    public void next()
    {
        try
        {
            rs.next();
        }
        catch(Exception e)
        {
           JOptionPane.showMessageDialog(null, "Error: "+e);
        }
    }
    
    public void previous()
    {
        try
        {
            rs.previous();
        }
        catch(Exception e)
        {
            JOptionPane.showMessageDialog(null, "Error: "+e);
        }
    }
    
    public boolean getFirstStatus()
    {
        try
        {
            if(rs.first())
            {
                temp = true;
            }
            
        }
        catch(Exception e)
        {
            JOptionPane.showMessageDialog(null, "Error: "+e);
        }
        
        return temp;        
    }
    
    
     public boolean getLastStatus()
    {
        try
        {
            if(rs.last())
            {
                temp = true;
            }
            
        }
        catch(Exception e)
        {
            JOptionPane.showMessageDialog(null, "Error: "+e);
        }
        
        return temp;        
    }
    
    public String getID()
    {
        try
        {
        str = rs.getString(1);
        }
        catch(Exception e)
        {
            JOptionPane.showMessageDialog(null, "Error: "+e);
        }
        
        return str;
    }
    
    public String getName()
    {
        try
        {
            str = rs.getString(2);
        }
        catch(Exception e)
        {
            JOptionPane.showMessageDialog(null, "Error: "+e);
        }
        
        return str;
    }
    
    public String getAddress()
    {
        try
        {
            str = rs.getString(3);
        }
        catch(Exception e)
        {
            JOptionPane.showMessageDialog(null, "Error: "+e);
        }
        
        return str;
    }
    
    public String getPhone()
    {
        try
        {
            str = rs.getString(4);
        }
        catch(Exception e)
        {
            JOptionPane.showMessageDialog(null, "Error: "+e);
        }
        
        return str;
    }
}

when I click the "Next" button, it just shows the result for once, then nothing! Which means then it is not navigating forward!! Anyway if I remove the buttonStatus() methods from JustTest.java file, everything is working fine!! What is the problem here? Please help

[Paul Clapham]

Your problem is at line 97 of the JustTest class.

[Yohan Weerasinghe]

Thanks for the reply Paul. I edited that, but still no good

This is what I did.

 JOptionPane.showMessageDialog(null,"Error: "+e);

[Yohan Weerasinghe]

Seems like it is locking the rs.next() method. Why is this? Why it is working after removing that buttonStatus() method???