Most simple code to populate JTable from ResultSet
I googled the whole day and no luck. I call getnPrintAllData() method after pressing OK button. So the code is:
public class DatabaseSQLiteConnection {
Connection conn = null;
PreparedStatement statement = null;
ResultSet res = null;
public DatabaseSQLiteConnection(){
try{
Class.forName("org.sqlite.JDBC");
conn = DriverManager.getConnection("jdbc:sqlite:test.sqlite");
statement = conn.prepareStatement("SELECT * from product_info;");
}
catch(Exception e){
e.printStackTrace();
}
}
public void getnPrintAllData(){
String name, supplier, id;
DefaultTableModel dtm = new DefaultTableModel();
Window gui = new Window(); //My JPanel class
try{
res = statement.executeQuery();
testResultSet(res);
ResultSetMetaData meta = res.getMetaData();
int numberOfColumns = meta.getColumnCount();
while (res.next())
{
Object [] rowData = new Object[numberOfColumns];
for (int i = 0; i < rowData.length; ++i)
{
rowData[i] = res.getObject(i+1);
}
dtm.addRow(rowData);
}
gui.jTable1.setModel(dtm);
dtm.fireTableDataChanged();
//////////////////////////
}
catch(Exception e){
System.err.println(e);
e.printStackTrace();
}
finally{
try{
res.close();
statement.close();
conn.close();
}
catch(Exception e){
e.printStackTrace();
}
}
}
public void testResultSet(ResultSet res){
try{
while(res.next()){
System.out.println("Product ID: "+ res.getInt("product_id"));
System.out.println("Product name: "+ res.getString("product_name"));
System.out.println("Supplier: "+ res.getString("supplier"));
}
}
catch(Exception e){
e.printStackTrace();
}
}
}
My testResultSet() method is working properly.
Now, how to change my code so that it works, or what is the most simple code to make DefaultTableModel from ResultSet ?
Thanks in advance.
Edit: I am reciving java.lang.IllegalStateException: SQLite JDBC: inconsistent internal state error.
I think the simplest way to build a model from an instance of ResultSet, could be as follows.
public static void main(String[] args) throws Exception {
// The Connection is obtained
ResultSet rs = stmt.executeQuery("select * from product_info");
// It creates and displays the table
JTable table = new JTable(buildTableModel(rs));
// Closes the Connection
JOptionPane.showMessageDialog(null, new JScrollPane(table));
}
The method buildTableModel:
public static DefaultTableModel buildTableModel(ResultSet rs)
throws SQLException {
ResultSetMetaData metaData = rs.getMetaData();
// names of columns
Vector<String> columnNames = new Vector<String>();
int columnCount = metaData.getColumnCount();
for (int column = 1; column <= columnCount; column++) {
columnNames.add(metaData.getColumnName(column));
}
// data of the table
Vector<Vector<Object>> data = new Vector<Vector<Object>>();
while (rs.next()) {
Vector<Object> vector = new Vector<Object>();
for (int columnIndex = 1; columnIndex <= columnCount; columnIndex++) {
vector.add(rs.getObject(columnIndex));
}
data.add(vector);
}
return new DefaultTableModel(data, columnNames);
}
UPDATE
Do you like to use javax.swing.SwingWorker? Do you like to use the try-with-resources statement?
public class GUI extends JFrame {
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
new GUI().setVisible(true);
}
});
}
private final JButton button;
private final JTable table;
private final DefaultTableModel tableModel = new DefaultTableModel();
public GUI() throws HeadlessException {
setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
table = new JTable(tableModel);
add(new JScrollPane(table), BorderLayout.CENTER);
button = new JButton("Load Data");
button.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
new SwingWorker<Void, Void>() {
@Override
protected Void doInBackground() throws Exception {
loadData();
return null;
}
}.execute();
}
});
add(button, BorderLayout.PAGE_START);
setSize(640, 480);
}
private void loadData() {
LOG.info("START loadData method");
button.setEnabled(false);
try (Connection conn = DriverManager.getConnection(url, usr, pwd);
Statement stmt = conn.createStatement()) {
ResultSet rs = stmt.executeQuery("select * from customer");
ResultSetMetaData metaData = rs.getMetaData();
// Names of columns
Vector<String> columnNames = new Vector<String>();
int columnCount = metaData.getColumnCount();
for (int i = 1; i <= columnCount; i++) {
columnNames.add(metaData.getColumnName(i));
}
// Data of the table
Vector<Vector<Object>> data = new Vector<Vector<Object>>();
while (rs.next()) {
Vector<Object> vector = new Vector<Object>();
for (int i = 1; i <= columnCount; i++) {
vector.add(rs.getObject(i));
}
data.add(vector);
}
tableModel.setDataVector(data, columnNames);
} catch (Exception e) {
LOG.log(Level.SEVERE, "Exception in Load Data", e);
}
button.setEnabled(true);
LOG.info("END loadData method");
}
}
I think this is the Easiest way to populate a table with ResultSet with a method like
FillTable(MyTable, "select * Customers;");
And a very simple method can be made as
public void FillTable(JTable table, String Query)
{
try
{
CreateConnection();
Statement stat = conn.createStatement();
ResultSet rs = stat.executeQuery(Query);
//To remove previously added rows
while(table.getRowCount() > 0)
{
((DefaultTableModel) table.getModel()).removeRow(0);
}
int columns = rs.getMetaData().getColumnCount();
while(rs.next())
{
Object[] row = new Object[columns];
for (int i = 1; i <= columns; i++)
{
row[i - 1] = rs.getObject(i);
}
((DefaultTableModel) table.getModel()).insertRow(rs.getRow()-1,row);
}
rs.close();
stat.close();
conn.close();
}
catch(InstantiationException | IllegalAccessException | SQLException e)
{
}
}
Well I'm sure that this is the simplest way to populate JTable from ResultSet, without any external library. I have included comments in this method.
public void resultSetToTableModel(ResultSet rs, JTable table) throws SQLException{
//Create new table model
DefaultTableModel tableModel = new DefaultTableModel();
//Retrieve meta data from ResultSet
ResultSetMetaData metaData = rs.getMetaData();
//Get number of columns from meta data
int columnCount = metaData.getColumnCount();
//Get all column names from meta data and add columns to table model
for (int columnIndex = 1; columnIndex <= columnCount; columnIndex++){
tableModel.addColumn(metaData.getColumnLabel(columnIndex));
}
//Create array of Objects with size of column count from meta data
Object[] row = new Object[columnCount];
//Scroll through result set
while (rs.next()){
//Get object from column with specific index of result set to array of objects
for (int i = 0; i < columnCount; i++){
row[i] = rs.getObject(i+1);
}
//Now add row to table model with that array of objects as an argument
tableModel.addRow(row);
}
//Now add that table model to your table and you are done :D
table.setModel(tableModel);
}