JDBC locking access db

Question

i can create the table from jframe. i can open the program and instantly insert records, but if i insert a table, then try and insert records i get sqlexception error saying database is locked by othe process and I DON'T have Access open or another instance of this program. but it does seem to write the new records. any help would be great. fully runnable code presuming you setup Coffee DSN. it locks on line 180 which is part of the tableExistsCreateNew method where i try and drop the table.
mike
screen output.
A Table already exists with data
Old table was deleted.
New table was created successfully
Table has data records, they will be deleted
An empty table exists
Error in creatingtable after dropping.Records were created successfully
import java.io.*;
import java.net.*;
import java.sql.*;
import javax.swing.JTextPane;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
* CoffeeDBAdmin.java
* Created on July 20, 2004, 1:33 PM
* @author Participant5
public class CoffeeDBAdmin extends javax.swing.JFrame {
/** Creates new form CoffeeDBAdmin */
Connection conn;
String message;
public CoffeeDBAdmin() {
initComponents();
createConnection();
/** 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.
private void initComponents() {//GEN-BEGIN:initComponents
jTextPane1 = new javax.swing.JTextPane();
jMenuBar1 = new javax.swing.JMenuBar();
MenuDatabase = new javax.swing.JMenu();
CreateTable = new javax.swing.JMenuItem();
Insert = new javax.swing.JMenuItem();
Retrieve = new javax.swing.JMenuItem();
Exit = new javax.swing.JMenuItem();
setTitle("CoffeeDBAdmin");
addWindowListener(new java.awt.event.WindowAdapter() {
public void windowClosing(java.awt.event.WindowEvent evt) {
exitForm(evt);
jTextPane1.setMinimumSize(new java.awt.Dimension(375, 200));
jTextPane1.setPreferredSize(new java.awt.Dimension(375, 200));
getContentPane().add(jTextPane1, java.awt.BorderLayout.CENTER);
MenuDatabase.setText("Database");
MenuDatabase.setActionCommand("MenuDatabase");
CreateTable.setText("Create Table");
CreateTable.addMouseListener(new java.awt.event.MouseAdapter() {
public void mouseReleased(java.awt.event.MouseEvent evt) {
CreateTableMouseReleased(evt);
MenuDatabase.add(CreateTable);
Insert.setText("Insert");
Insert.addMouseListener(new java.awt.event.MouseAdapter() {
public void mouseReleased(java.awt.event.MouseEvent evt) {
InsertMouseReleased(evt);
MenuDatabase.add(Insert);
Retrieve.setText("Retrieve");
Retrieve.setActionCommand("Retrieve");
Retrieve.addMouseListener(new java.awt.event.MouseAdapter() {
public void mouseReleased(java.awt.event.MouseEvent evt) {
RetrieveMouseReleased(evt);
MenuDatabase.add(Retrieve);
Exit.setText("Exit");
Exit.addMouseListener(new java.awt.event.MouseAdapter() {
public void mouseReleased(java.awt.event.MouseEvent evt) {
ExitMouseReleased(evt);
MenuDatabase.add(Exit);
jMenuBar1.add(MenuDatabase);
setJMenuBar(jMenuBar1);
pack();
}//GEN-END:initComponents
private void ExitMouseReleased(java.awt.event.MouseEvent evt) {//GEN-FIRST:event_ExitMouseReleased
// TODO add your handling code here:
exitRoutine();
}//GEN-LAST:event_ExitMouseReleased
public void createConnection()
try{
//load JDBC ODBC driver
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
//setup the connection
String url = "jdbc:odbc:Coffee";
conn = DriverManager.getConnection
(url, "myLogin", "myPassword");
catch (Exception e)
message = "DSN Error.";
JOptionPane.showInternalMessageDialog(jMenuBar1,
message);
//e.printStackTrace();
public void createTable()
try
Statement stmt = conn.createStatement();
//jTextPane1.setText(null);
//stmt.executeUpdate("DROP TABLE COFFEES");
stmt.executeUpdate("CREATE TABLE COFFEES " +
"(COFFEE_NAME VARCHAR(32), SUP_ID INTEGER, PRICE FLOAT, " +
"SALES INTEGER, TOTAL INTEGER)");
System.out.println();
//jTextPane1.setText(null);
stmt.close();
catch(NullPointerException npe)
//we are gonna leave this empty because if you try and call an update
//without having a database, this exception will occur. it is not
//necessary to throw this exception as the program print a message and
//will exit if there is a database problem.
message = "Database Error";
JOptionPane.showInternalMessageDialog(jMenuBar1,
message);
catch (SQLException tableExists)
//System.out.println("Table already exists");
this.tableExistsCreateNew();
public void tableExistsCreateNew()
try{
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery("SELECT Coffee_Name, " +
"Price FROM COFFEES");
if((rs.next() == true))
message = "A Table already exists with data\n";
else
message = "An empty table exists\n";
rs = stmt.executeQuery("SELECT Coffee_Name, Price " +
"FROM COFFEES");
jTextPane1.setText(jTextPane1.getText() + "\n" + message);
stmt.executeUpdate("DROP TABLE COFFEES");
jTextPane1.setText(jTextPane1.getText() +
"Old table was deleted.\n");
stmt.executeUpdate("CREATE TABLE COFFEES " +
"(COFFEE_NAME VARCHAR(32), SUP_ID INTEGER, PRICE FLOAT, " +
"SALES INTEGER, TOTAL INTEGER)");
jTextPane1.setText(jTextPane1.getText() +
"New table was created successfully\n");
//this.createRecords();
stmt.close();
//rs.close();
catch(NullPointerException npe)
//we are gonna leave this empty because if you try and call an update
//without having a database, this exception will occur. it is not
//necessary to throw this exception as the program print a message and
//will exit if there is a database problem.
jTextPane1.setText(jTextPane1.getText() + "\nDatabase Error.");
JOptionPane.showInternalMessageDialog(jMenuBar1,"Database" +
" Error");
catch(Exception e)
System.out.println("\nerror in creating table after dropping\n");
e.printStackTrace();
//System.exit(0);
jTextPane1.setText(jTextPane1.getText() + "\nError in creating" +
"table after dropping.\n");
JOptionPane.showInternalMessageDialog(jMenuBar1,
"Error in creating table after dropping.\n");
public void createRecords()
try
{ Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery("SELECT " +
"Coffee_Name, Price " + "FROM COFFEES");
if(rs.next() == false)
jTextPane1.setText(jTextPane1.getText() +
"\nTable has data records, they will be " +
" deleted\n\n");
//stmt.executeUpdate("DROP TABLE COFFEES");
tableExistsCreateNew();
stmt.executeUpdate("INSERT INTO COFFEES " +
"(Coffee_Name, SUP_ID, Price) " +
"VALUES ('Colombian', 101, 7.99)");
stmt.executeUpdate("INSERT INTO COFFEES "+
"(Coffee_Name, SUP_ID, Price) " +
"VALUES ('French_Roast', 49, 8.99)");
jTextPane1.setText(jTextPane1.getText() + "Records" +
" were created successfully\n");
//rs.close();
stmt.close();
catch (Exception e)
//System.out.println("Error in creating records");
//e.printStackTrace();
//System.exit(0);
message = "The Table you requested does not exist.";
JOptionPane.showInternalMessageDialog(jMenuBar1,message);
public void printRecords()
try
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery("SELECT Coffee_Name, Price " +
"FROM COFFEES");
jTextPane1.setText("Coffee Prices\n");
//System.out.println("Coffee Prices");
while(rs.next())
jTextPane1.setText((jTextPane1.getText() + rs.getString(1)
+ " " + rs.getDouble(2) + "\n" ));
// System.out.println(rs.getString(1) + " " +
// rs.getDouble(2) + "\n" );
//rs.close();
stmt.close();
//conn.close();
catch(NullPointerException npe)
//we are gonna leave this empty because if you try and call an update
//without having a database, this exception will occur. it is not
//necessary to throw this exception as the program print a message and
//will exit if there is a database problem.
message = "Database Error";
jTextPane1.setText(jTextPane1.getText() + "\n" +
message);
JOptionPane.showInternalMessageDialog(jMenuBar1,"You " +
"cannot retrieve" + "records from a null or " +
"uncreated table");
//System.exit(0);
catch (Exception e)
//message = "Error in printing records";
jTextPane1.setText(jTextPane1.getText() +"\n" +
message);
//System.exit(0);
e.printStackTrace();
//JOptionPane.showInternalMessageDialog(jMenuBar1,"You cannot retrieve" +
//"records from a null or uncreated table");
public void exitRoutine()
try{
conn.close();
dispose();
System.exit(0);
catch (Exception e)
message = "error closing connection";
JOptionPane.showInternalMessageDialog(jMenuBar1,
message);
//e.printStackTrace();
private void RetrieveMouseReleased(java.awt.event.MouseEvent evt) {//GEN-FIRST:event_RetrieveMouseReleased
// TODO add your handling code here:
printRecords();
}//GEN-LAST:event_RetrieveMouseReleased
private void InsertMouseReleased(java.awt.event.MouseEvent evt) {//GEN-FIRST:event_InsertMouseReleased
// TODO add your handling code here:
createRecords();
}//GEN-LAST:event_InsertMouseReleased
private void CreateTableMouseReleased(java.awt.event.MouseEvent evt) {//GEN-FIRST:event_CreateTableMouseReleased
// TODO add your handling code here:
createTable();
}//GEN-LAST:event_CreateTableMouseReleased
/** Exit the Application */
private void exitForm(java.awt.event.WindowEvent evt) {//GEN-FIRST:event_exitForm
dispose();
System.exit(0);
}//GEN-LAST:event_exitForm
* @param args the command line arguments
public static void main(String args[]) {
new CoffeeDBAdmin().show();
// Variables declaration - do not modify//GEN-BEGIN:variables
private javax.swing.JMenuItem CreateTable;
private javax.swing.JMenuItem Exit;
private javax.swing.JMenuItem Insert;
private javax.swing.JMenu MenuDatabase;
private javax.swing.JMenuItem Retrieve;
private javax.swing.JMenuBar jMenuBar1;
private javax.swing.JTextPane jTextPane1;
// End of variables declaration//GEN-END:variables

Answer 1

Are you releasing your connections appropriately?