Invalid Handle SQLException - HELP!!

Question

I am using a timer and a counter to automaticallyinsert records into my table at predefined intervals. The counter is used to provide the unique PersonID. My first record is inserted fine, where PersonID is 0. As soon as PersonID is 1 or more, I get an Invalid Handle SQLException.
The line which is generating the error is:
stmt.setInt(1, id);
Relevent code is given below:
     * Insert a record into the Person table,
    private void insertPersonRecord(int id) {
        try {
            connection.setAutoCommit(false);
System.err.println("ID: " + id);
            stmt.setInt(1, id);
            stmt.setString(2, "First_name");
            stmt.setString(3, "Sur_name");
            stmt.executeUpdate();
            connection.commit();
            connection.setAutoCommit(true);
            stmt.close();
System.err.println("Person record inserted");
        catch(SQLException sqlex) {
System.err.println("Unable to insert person record");
            sqlex.printStackTrace();
     * Set up timer actions.
    class InsertTask extends TimerTask {
        public void run() {
            insertPersonRecord(id);
            id++;
            if (id == 20) {
System.err.println("Timer stopped - shutting down");                   
                shutDown();
    }I just can't work this out. Any ideas?
Cheers,
Sandra.

Answer 1

More code:
* Simple JDBC prototype using the Sports.mdb MSAccess database.
public class JDBCPrototype {
    private Connection connection;
    private PreparedStatement stmt;
    private Timer timer;
    private int id = 0;
    public JDBCPrototype() {
        // Connect to the Sports database using a JDBC-ODBC bridge.
        final String url = "jdbc:odbc:Sports";
        final String username = "JDBCPrototype";
        final String password = "test";
          // Load the driver to allow connection to the database          
        try {
            Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
            connection = DriverManager.getConnection(url, username, password);
System.err.println("Connection established");           
        catch (ClassNotFoundException cnfex) {
System.err.println("Failed to load JDBC/ODBC driver.");
            cnfex.printStackTrace();
            System.exit(1);
        catch (SQLException sqlex) {
System.err.println("Unable to connect");
            sqlex.printStackTrace();
        String insertString = "INSERT INTO PARTICIPANTS " +
            "VALUES (?, ?, ?)";
        try {
            stmt = connection.prepareStatement(insertString);    
        catch(SQLException sqlex) {
            sqlex.printStackTrace();
System.err.println("Unable to prepare statement");           
        //empty database
        try {
            Statement statement = connection.createStatement();
            statement.executeUpdate
                    ("DELETE * FROM PARTICIPANTS");
System.err.println("Table emptied");
        catch(SQLException sqlex) {
System.err.println("Unable to empty table");
            sqlex.printStackTrace();
        startTimer();
     * Insert records using the timer.
    private void startTimer() {
          timer = new Timer();       
        final int DELAY = 50;
        timer.schedule(new InsertTask(), 0, DELAY);    
System.err.println("Timer started");
    }