Username and password check problem

Question

I have learned Java for 3 months and I am going to finish a project for the school. I have had some problems on username & password check and authorization from SQL database using ODBC. Any source code I can learn from?
Thanks in advance.

Answer 1

I'm not too clear on what you exactly want, but here's an example from my book using "username", "password", and a "database". I can send you the db file if you need to see it. I hope this helps.
// Fig. 18.24: TableDisplay.java
// This program displays the contents of the Authors table
// in the Books database.
import java.sql.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
public class TableDisplay extends JFrame {
private Connection connection;
private JTable table;
public TableDisplay()
// The URL specifying the Books database to which
// this program connects using JDBC to connect to a
// Microsoft ODBC database.
String url = "jdbc:odbc:Books";
String username = "anonymous";
String password = "guest";
// Load the driver to allow connection to the database
try {
Class.forName( "sun.jdbc.odbc.JdbcOdbcDriver" );
connection = DriverManager.getConnection(
url, username, password );
catch ( ClassNotFoundException cnfex ) {
System.err.println(
"Failed to load JDBC/ODBC driver." );
cnfex.printStackTrace();
System.exit( 1 ); // terminate program
catch ( SQLException sqlex ) {
System.err.println( "Unable to connect" );
sqlex.printStackTrace();
getTable();
setSize( 450, 150 );
show();
private void getTable()
Statement statement;
ResultSet resultSet;
try {
String query = "SELECT * FROM Authors";
statement = connection.createStatement();
resultSet = statement.executeQuery( query );
displayResultSet( resultSet );
statement.close();
catch ( SQLException sqlex ) {
sqlex.printStackTrace();
private void displayResultSet( ResultSet rs )
throws SQLException
// position to first record
boolean moreRecords = rs.next();
// If there are no records, display a message
if ( ! moreRecords ) {
JOptionPane.showMessageDialog( this,
"ResultSet contained no records" );
setTitle( "No records to display" );
return;
setTitle( "Authors table from Books" );
Vector columnHeads = new Vector();
Vector rows = new Vector();
try {
// get column heads
ResultSetMetaData rsmd = rs.getMetaData();
for ( int i = 1; i <= rsmd.getColumnCount(); ++i )
columnHeads.addElement( rsmd.getColumnName( i ) );
// get row data
do {
rows.addElement( getNextRow( rs, rsmd ) );
} while ( rs.next() );
// display table with ResultSet contents
table = new JTable( rows, columnHeads );
JScrollPane scroller = new JScrollPane( table );
getContentPane().add(
scroller, BorderLayout.CENTER );
validate();
catch ( SQLException sqlex ) {
sqlex.printStackTrace();
private Vector getNextRow( ResultSet rs,
ResultSetMetaData rsmd )
throws SQLException
Vector currentRow = new Vector();
for ( int i = 1; i <= rsmd.getColumnCount(); ++i )
switch( rsmd.getColumnType( i ) ) {
case Types.VARCHAR:
currentRow.addElement( rs.getString( i ) );
break;
case Types.INTEGER:
currentRow.addElement(
new Long( rs.getLong( i ) ) );
break;
default:
System.out.println( "Type was: " +
rsmd.getColumnTypeName( i ) );
return currentRow;
public void shutDown()
try {
connection.close();
catch ( SQLException sqlex ) {
System.err.println( "Unable to disconnect" );
sqlex.printStackTrace();
public static void main( String args[] )
final TableDisplay app = new TableDisplay();
app.addWindowListener(
new WindowAdapter() {
public void windowClosing( WindowEvent e )
app.shutDown();
System.exit( 0 );