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How can I populate my JTable with my embedded database?

I am having trouble showing my database filled JTable within my GUI application.
My code below runs through and creates a GUI with a panel, I then create my JTable and add it onto my application. I then run through a method that supposedly populates the table. After the populating has finished, nothing shows.
Dissecting my code, I'm led to believe somewhere is causing the data not to parse into my table, for some unknown reason, which is why I have come here.
At the click of a button, this code entails:
JTable tigerTable = new JTable();
JPanel centerPanel = new JPanel();
centerPanel.add(tigerTable, new GridBagConstraints());
FillTable(tigerTable, "SELECT * FROM TIGER_INFO");
The FillTable method as follows:
//Add buildTableModel method
public void FillTable(JTable table, String Query)
{
try
{
Class.forName("org.apache.derby.jdbc.EmbeddedDriver").newInstance();
Connection conn = DriverManager.getConnection("jdbc:derby:STOCK_CONTROL");
Statement stat = conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_READ_ONLY);
ResultSet rs = stat.executeQuery(Query);
System.out.println("Connected");
//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 |
ClassNotFoundException |
SQLException e)
{
System.out.println(e);
e.printStackTrace();
}
}
Doing so creates the application, but does not show any table with data. My database contains 3 columns and 3 rows, but I do not see my data displayed inside a JTable.
My question is, how can I populate my JTable with my database and display it correctly on my GUI application?
If you need anything else, please let me know and I will provide as much as I can.
Thank you in advance.

I think you mix the operation, i suggest to use this instruction :
Create a Bean, or Entity to store the information of your Object
Get the List of your data,
Display your data in your JTable,
So you can use this to display your data in your JTable :
....
List<TIGER_INFO> list = new ArrayList<>();//create a List of data
while (rs.next()){
//fill data in your List
list.add(new TIGER_INFO(rs.getTYPExxx("att1"), rs.getTYPExxx("att2"), rs.getTYPExxx("att3"));
}
//when you finish call your function which display your data :
fillData(list);
....
Fill date method can look like this :
private void fillData(List<TIGER_INFO> list) {
DefaultTableModel model = (DefaultTableModel) jTableName.getModel();
while (model.getRowCount() > 0) {
for (int i = 0; i < model.getRowCount(); i++) {
model.removeRow(i);
}
}
for (TIGER_INFO obj : list) {
model.addRow(new Object[]{
obj.getAttribute1(),
obj.getAttribute2,
obj.getAttribute3
});
}
}

I recommend to write a class extending AbstractTableModel. Add a function to this class filling the content based on a SQL-Statement. Then it will look something like:
TigerTableModel tigerModel = new TigerTableModel(dbConnection);
tigerModel.executeQuery("select * FROM TIGER_INFO");
JTable tigerTable = new JTable(tigerModel);
or you create a generic TableModel that is able to run every SQL-statement, so you are very flexible in your project.

I have found the solution - I've been trying to wrap my head around the problem for way too long, and I finally fixed it.
Try setting the table model manually first.
JTable tigerTable = new JTable();
tigerTable.setModel(new DefaultTableModel(0, numberOfColumns));
When you don't specify a model, the JTable creates an anonymous inner class and generally doesn't behave how you want it to.

add column to jtable dynamically on netbeans

my code is this :
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
DefaultTableModel model=(DefaultTableModel)pl.getModel();
String urlBaseDonnes="jdbc:mysql://localhost:3306/test";
Connection con;
try{
Class.forName("com.mysql.jdbc.Driver");
}catch(ClassNotFoundException ex){
System.out.println(ex);
}
try{
con =DriverManager.getConnection(urlBaseDonnes,"root","");
try (Statement stmt = con.createStatement()) {
ResultSet rs = stmt.executeQuery("SELECT * FROM news");
ResultSetMetaData rsMetaData = rs.getMetaData();
int numberOfColumns = rsMetaData.getColumnCount();
System.out.println("resultSet MetaData column Count=" + numberOfColumns);
int j=0;
pl.setModel(new javax.swing.table.DefaultTableModel(new Object [][] {},new String [] {"ddd","fgg","nl"}));
// get the name of the column, and changing it
for (int i = 1 ; i <= numberOfColumns; i++) {
ChangeName(pl,j,rsMetaData.getColumnName(i));
System.out.println(rsMetaData.getColumnName(i));
System.out.println(j);
j= j+1;
}
String query="SELECT * FROM news";
rs=stmt.executeQuery(query);
//Show the database
while(rs.next()){
String id=rs.getString("id");
String titre=rs.getString("titre");
String contenu=rs.getString("contenu");
model.addRow(new Object[]{id,titre,contenu});
}
rs.close();
}
con.close();
System.out.println("close the database");
}catch(SQLException ex){
System.out.println(ex);
}
}
My goal is to change the name of the columns dynamically when i change the name of my table, this code can change the name of the column but when it's come to showing the content of the database it doesn't work, also i can't add column, for exemple if i choose a table that have 4 column, i'll have an error. I tried to add column using a DefaultTableModel but it didn't work.
could you please help me with the part of adding column dynamically ? and tell me why this code doesn't show what's on the database ?
Thanks

that the data that are in my database are not shown. this code only changes the name of the column.
First you access the TableModel of the table:
DefaultTableModel model=(DefaultTableModel)pl.getModel();
Then you change the TableModel of the table:
pl.setModel(new javax.swing.table.DefaultTableModel(new Object [][] {},new String [] {"ddd","fgg","nl"}));
Then you add the data from the database to the "old" model:
model.addRow(new Object[]{id,titre,contenu});
So the data is NOT added to the current model.
If you want to create a new model then your code should be something like:
DefaultTableModel model = DefaultTableModel(Object[] columnNames, int rowCount);
pl.setModel( model );
Then your code will add the database data to the real model.
The question is why are you trying to hardcode the column name? When you do a select * from the database you don't know how many columns of data will be returned. You should be using more generic code. See the TableFromDatabaseExample.java code from Table From Database.

JTable does not refresh with fireTableDataChanged()

I have a JTable with DefaultTableModel. I want to refresh the JTable whenever I click on the JTable. Below is my code using modelTarget.fireTableDataChanged(); to refresh the JTable.
but the values shown within the JTable does not change when click action is performed.
Initializing component and inserting values into table:
final TestClass test = new TestClass();
String sql = "SELECT * FROM student";
ResultSet rs = test.stmt.executeQuery(sql);
JTable table = new JTable();
DefaultTableModel model = new DefaultTableModel(0, 0);
String header[] = new String[] { "ID", "Name"};
model.setColumnIdentifiers(header);
table.setModel(model); //set model into table object
while (rs.next())
{
int id = rs.getInt("id");
String name = rs.getString("name");
//Add rows into table
model.addRow(new Object[] { id, name});
}
Listener for JTable:
table.addMouseListener(new MouseAdapter()
{
public void mouseClicked(MouseEvent e) {
String sql = "UPDATE student " + "SET name='Alice' " + "WHERE id=7";
JTable target = (JTable)e.getSource();
int row = target.getSelectedRow();
try{test.stmt.executeUpdate(sql);}
catch(SQLException err){System.out.println("SQL Error!");};
System.out.println(target.getModel().getValueAt(row, 0)); //get row value
DefaultTableModel modelTarget = (DefaultTableModel) target.getModel();
modelTarget.fireTableDataChanged(); //JTable did not refresh with this code
}
});
Que: Do I need to do anything else to the table model before using .fireTableDataChanged() ? If not, what else can I do to let the JTable refresh?
EDIT: I am suspecting that the table model did not receive the changes which I made to the sql tables. So is there any way I can "refresh" or "update" the table model?
EDIT: I managed to let it work now by writing a method to empty all rows in current model and re-add all the rows according to the updated database. I did not use fireTableDataChanged() at all. Anyone in human history managed to let fireTableDataChanged() work?

JTable doesn't show the newly inserted row/data

I have a JTable and I populte the table as follows:
jTable_Std_info.setModel(DBControler.getALLStudents());
And the following is a static method in a class named DBControler which retrieves all the data from the database(Oracle).
public static DefaultTableModel getALLStudents() throws SQLException, Exception {
DefaultTableModel tableModel = new DefaultTableModel();
Vector rows = new Vector();
Vector columns = new Vector();
try {
conn = geConnection();
cst = conn.prepareCall("{? = call std_getInfoFunc}");
cst.registerOutParameter(1, oracle.jdbc.OracleTypes.CURSOR);
cst.execute();
res = (ResultSet) cst.getObject(1);
System.out.print(res);
ResultSetMetaData rsm = res.getMetaData();
for (int i = 1; i <= rsm.getColumnCount(); i++) {
columns.addElement(rsm.getColumnName(i));
}
int row = 0;
while (res.next()) {
Vector vRow = new Vector(); //to store the current row
//System.out.println("Row " +row+"\n");
for (int i = 1; i <= rsm.getColumnCount(); i++) {
String columnValue = res.getString(i);
vRow.addElement(columnValue);
}
row += 1;
rows.addElement(vRow);
}
tableModel.setDataVector(rows, columns);
} catch (SQLException e) {
e.printStackTrace();
} finally {
res.close();
conn.close();
}
return tableModel;
}
So far everything works fine, but the problem is that if I insert a new record in the database, the JTable doesn't get the newly inserted row/data. Why is that and how can I fix this problem?
UPDATE:
It's retrieving the data when I commit my new insertion. So do I have to commit each time I update? Or is there any other ways to do this?

I think that you looking for Oracle Built-In Database Change Notification, not sure if is accesible for Oracle's in free-versions, if not then never mind, for MySQL is there two or three similair API for Java JDBC

But the problem is that if I insert a new record in the database, the JTable doesn't get the newly inserted row/data. Why is that?
The TableModel doesn't know when the database is updated.
and how can I fix this problem?
If your application is adding the row to the database then it also needs to add a row to the TableModel at the same time.

SQL data and JTable

I'm trying one sample program for practice and i want to display results of database in JTable. The problem is i have no idea how to do that. I know how to get data from database and display it on text field or console but never tried with JTable. How to do that ?
Consider that i've table which is holding information like person name, age, city and date. i want it to be displayed via JTable. Also is it possible to update the JTable display if i add the option of adding more details in program(i mean adding entries to db then that will show immediately in JTable )?
Any suggestions, pointers on how to proceed is appreciated. Thanks in advance.

JDBC + JTable # google:
Hacking Swing: A JDBC Table Model
Mastering the JTable
Making SQL Queries with JDBC and Displaying Results with Swing

here is the code
public static TableModel resultSetToTableModel(ResultSet rs) {
try {
ResultSetMetaData metaData = rs.getMetaData();
int numberOfColumns = metaData.getColumnCount();
Vector<String> columnNames = new Vector<String>();
// Get the column names
for (int column = 0; column < numberOfColumns; column++) {
columnNames.addElement(metaData.getColumnLabel(column + 1).toUpperCase());
}
// Get all rows.
Vector<Vector<Object>> rows = new Vector<Vector<Object>>();
while (rs.next()) {
Vector<Object> newRow = new Vector<Object>();
for (int i = 1; i <= numberOfColumns; i++) {
newRow.addElement(rs.getObject(i));
}
rows.addElement(newRow);
}
return new DefaultTableModel(rows, columnNames);
}
catch (Exception e)
{
e.printStackTrace();
return null;
}
}
you can call this method such that way
void update_Table() throws ParseException
{
// we used this try catch so that values in table automatically show(without clicking on any button) when the dialog box open
try
{
Connection con=MSUTIL.getMSConnection();
PreparedStatement pst=con.prepareStatement("select payment_mode from PaymentMode");
ResultSet rs=pst.executeQuery();
//here i call that method
table.setModel(resultSetToTableModel(rs));
table.getTableHeader().setFont(new Font("SansSerif", Font.BOLD, 14));
while(rs.next())
{
mp.paymentmode_ComboBox.addItem(rs.getString("payment_mode"));
}
}
catch(SQLException e)
{
e.printStackTrace();
}
finally
{
//this method is for closing the connection
MSUTIL.cleanUp(con, pst, rs);
}
}