Updating records in the database problem...

Question

hi, hello to all members, my problem is this, i can't update my records, my table name is UsrTable with a two fields only, which UsrName and Password. all i want to do is when the user wants to sign up and enters there username and password the database will be updated of the new record. i paste the sorce code in here to make it precise co'z i cant figure out how to update the database, sorry if the coding is too long and not good , im just a beginner in JAVA especially using JDBC.
****START CODE*****
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.sql.*;
public class SignIn extends JFrame
private JPanel jInput;
private JPanel jButton;
private JButton Savebtn,Exitbtn;
private JLabel userlbl,passlbl,connectionLabel;
private JTextField Usertxt;
private JPasswordField Passtxt;
public static final String DRIVER = "sun.jdbc.odbc.JdbcOdbcDriver";
public static final String url = "jdbc:odbc:UserInfo";
public static final String DATABASE = "\\User.mdb";
private Connection connect ;
public String tmpUser,tmpPass,query;
public SignIn()
super("Create your Account..");
setResizable(false);
ImageIcon imgIcon = new ImageIcon("c:/JavaCourseware/Images/cdicon.jpg");
this.setIconImage(imgIcon.getImage());
addWindowListener(new WindowAdapter()
{ // Opens addWindowListener method
public void windowClosing(WindowEvent e)
{ // Opens windowClosing method
int result;
result = JOptionPane.showConfirmDialog( null,"Are you sure you want to exit?",
"Confirmation Required...", JOptionPane.YES_NO_OPTION );
if(result == JOptionPane.YES_OPTION)
System.exit(0);
else
return;
} // Closes windowClosing method
}); // Closes addWindowListener method
try
InitComp();
catch(Exception e)
public void InitComp() throws Exception
Usertxt = new JTextField(15);
Passtxt = new JPasswordField(15);
connectionLabel = new JLabel();
userlbl = new JLabel("Enter your username: ");
passlbl = new JLabel("Enter your password: ");
Savebtn = new JButton("Save");
Exitbtn = new JButton("Exit");
this.setSize(new Dimension(320,150));
this.setLocationRelativeTo(null);
this.getContentPane().setBackground(Color.blue);
connectionLabel.setForeground(Color.YELLOW);
connectionLabel.setBackground(Color.BLUE);
connectionLabel.setFont(new Font("Arial", Font.PLAIN , 12));
buildTxtInput();
buildBtn();
this.getContentPane().add(connectionLabel,BorderLayout.NORTH);
this.getContentPane().add(jInput,BorderLayout.CENTER);
this.getContentPane().add(jButton,BorderLayout.SOUTH);
//make a connection
try
//url = "jdbc:odbc:UserInfo";
Class.forName(DRIVER);
connect = DriverManager.getConnection(url);
connectionLabel.setText("You have made a successful connection to: " + DATABASE);
catch(ClassNotFoundException cnfx)
cnfx.printStackTrace();
connectionLabel.setText("Connection unsuccessful" + cnfx.toString());
catch (SQLException sqlx)
sqlx.printStackTrace();
connectionLabel.setText("Connection unsuccessful" + sqlx.toString());
catch (Exception ex)
ex.printStackTrace();
connectionLabel.setText("Connection unsuccessful" + ex.toString());
Savebtn.addActionListener(new ActionListener()
public void actionPerformed(ActionEvent e)
try
Statement state = connect.createStatement();
if (Usertxt.getText().equals("") && Passtxt.getText().equals(""))
connectionLabel.setText("Invalid Input!");
JOptionPane.showMessageDialog( null, "Invalid Entry", "Saving Abort...", JOptionPane.INFORMATION_MESSAGE );
state.close();
else
state.executeUpdate("INSERT INTO UsrTable" +
"VALUE UsrName = '" +
Usertxt.getText() +"' AND Password = '" +
Passtxt.getText() +"'");
JOptionPane.showMessageDialog(null, "Your account is already created!","Thank you...",
JOptionPane.INFORMATION_MESSAGE);
state.close();
catch (SQLException sqlex)
sqlex.printStackTrace();
connectionLabel.setText(sqlex.toString());
});//end of Save Listener
public static void main(String args[])
SignIn Signfrm = new SignIn();
Signfrm.show();
private void buildTxtInput()
jInput = new JPanel();
jInput.setLayout( new GridLayout(2, 2, 0, 10) );
//user.setForeground(Color.yellow);
jInput.setBorder(BorderFactory.createTitledBorder(""));
//pass.setForeground(Color.yellow);
jInput.add(userlbl);
jInput.add(Usertxt);
jInput.add(passlbl);
jInput.add(Passtxt);
private void buildBtn()
jButton = new JPanel();
jButton.setLayout( new GridLayout(1, 1, 10, 10) );
jButton.setBorder(BorderFactory.createRaisedBevelBorder());
jButton.add(Savebtn);
jButton.add(Exitbtn);
}//end of class
***END PROGRAM***
im hoping there's someone can help me with this, co'z im badly need it.thanks..again,

Answer 1

hi! i followed your code, but i get a different error i dont know what is the meaning of error, first heres my code i write...thanks for the fast reply co'z i badly need it.
Savebtn.addActionListener(new ActionListener()
public void actionPerformed(ActionEvent e)
               String password = new String (Passtxt.getPassword());
if (IDtxt.getText().equals ("")) {
                    JOptionPane.showMessageDialog (null, "Member's Id not Provided.");
                    IDtxt.requestFocus();
else if (Usertxt.getText().equals ("")) {
                    Usertxt.requestFocus();
                    JOptionPane.showMessageDialog (null, "Username not Provided.");
               else if (password.equals ("")) {
                    Passtxt.requestFocus();
                    JOptionPane.showMessageDialog (null, "Password not Provided.");
               else {
                    try {     //INSERT Query to Add Book Record in Table.
                         String q = "UPDATE UsrTable "+"SET UsrName = '"+Usertxt.getText() + "' " +
"AND Password = '" + password + "'"+"WHERE ID = '" + ID + "'";
                         int result = st.executeUpdate(q);                              if (result == 1) {               .
                              JOptionPane.showMessageDialog (null, "New User has been Created.");
                              Usertxt.setText ("");
                              Passtxt.setText ("");
                              Usertxt.requestFocus ();
                         else {                                                        JOptionPane.showMessageDialog   (null, "Problem while Creating the User.");
                              Usertxt.setText ("");
                              Passtxt.setText ("");
                              Usertxt.requestFocus ();
                    catch (SQLException sqlex) { }
and heres the error...
java.lang.NullPointerException
at CreateAcc$3.actionPerformed(CreateAcc.java:179)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1786)
at javax.swing.AbstractButton$ForwardActionEvents.actionPerformed(AbstractButton.java:1839)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:420)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:258)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:245)
at java.awt.Component.processMouseEvent(Component.java:5100)
at java.awt.Component.processEvent(Component.java:4897)
at java.awt.Container.processEvent(Container.java:1569)
at java.awt.Component.dispatchEventImpl(Component.java:3615)
at java.awt.Container.dispatchEventImpl(Container.java:1627)
at java.awt.Component.dispatchEvent(Component.java:3477)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:3483)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3198)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3128)
at java.awt.Container.dispatchEventImpl(Container.java:1613)
at java.awt.Window.dispatchEventImpl(Window.java:1606)
at java.awt.Component.dispatchEvent(Component.java:3477)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:456)
at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:201)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:151)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:145)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:137)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:100)