Initial headers in JTable

Hi
I am having a problem using AbstractTableModel. The thing is that it is working perfectly for my application but I can get the header to appear with the initial names that I am setting. I am following some examples that I found on how to use this class, but in all of them the headers are declared at the begining in an String array;
e.g. String[] headers= {"Last", "Name", "Sex"}
But on the rest of the code I can't find where these values are actually set as headers for the table. When the table is displayed I get "A", "B", and "C" as the headers.
Thanks in advance

Once that you have your clumn names you must to put obn the Model.....
String[] headers= {"Last", "Name", "Sex"}
       // Create a model of the data.
        TableModel dataModel = new AbstractTableModel() {
            public String getColumnName(int column) {return headers[column];} //NOTE THIS ROW...

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http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6568959
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Hello
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import javax.swing.event.TableColumnModelEvent;
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Anybody ever done something like that ?
I need to display a very large grid, where the headers have a fairly long text, but each cell only has a single character in it, so I was thinking of making the headers vertical.
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Actually I am looking for a way to show text on an angle in the header :-)

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Hello
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Hi
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Thanks

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import java.awt.event.*;
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          public Object getValueAt(int r, int c) {return data[r][c];}
          public String getColumnName(int c) {return headers[c];}
     JTable jt = new JTable(tm);
     JScrollPane jsp = new JScrollPane(jt);
          jf.getContentPane().add(jsp, BorderLayout.CENTER);
          jf.setVisible(true);
public static void main(String args[]){
     DisplayTable dt = new DisplayTable(Database Parameters to be given here);

You could generalize it, but it gets tricky to deal with the data types and if the JTable is editable because you would read the DB table data at run time. Using the ResultSetMetaData, you would be able to find the column type too. But, how can we cast an object at run-time?
Below, I have provided an overview as of doing a read-only (all-strings version) of it. You may have some ideas from there.
The database parameters that you pass to the constructor would tell the model where to connect and which DB table to read the data from. Couple of options:
1. You can read the data in the constructor of DisplayTable into final variables and have the inner class (model) set its data and headers from those variables.
Or
2. Pull out the model as a separate class extending AbstractTableMode. Doing this, you can pass on the DB information to the model and have the model talk to the DB.
And, I would use dynamic datastructures like Vector or List instead of arrays.
You would have the following logic wherever you chose to talk to the DB:
I am assuming that you are trying to read a complete DB table into your JTable (or may be you would pass a SELECT-query alongwith your DB information). Whatever may be the case, you would execute a select- to the DB and get a resultset back. Using that you would be able to get the ResultSetMetaData, which will give you the column count and column names. You may chose to use these column names as the header names for your JTable. With the column count you would query every row to get the object at each column.
Here is a sample model:
class MyModel extends AbstractTableModel {
    ArrayList columnNames = new ArrayList();
    ArrayList data = new ArrayList();
    MyModel(<DB Info>) {
        // Use the DB info and get the resultset
        ResultSetMetaData rsm = rs.getMetaData();
        int col = rsm.getColumnCount();
        for(int i=1; i<=col; i++) {
            columnNames.add(rsm.getColumnName(i));
        // Read the data
        while(rs.next()) {
            ArrayList row = new ArrayList();
            data.add(row);
            for(int j=1; j<=col; j++) {
                // Here is the tricky part which I did not figure yet. For now, I am reading in all as Strings.
                row.add(rs.getObject(j).toString());
    public String getColumnName(int c) {
        return (String)columnNames.get(c);
    public int getColumnCount() {
        return columnNames.size();
    public Object getValueAt(int r,int c) {
        ArrayList row = (ArrayList)data.get(r);
        return (String)row.get(c);
    public int getRowCount() {
        return data.size();
}If you figured a way to handle run-time casting, please let us know.
HTH.
Vijay

Multi line headers

Does anyone know how to have multiple line headers in JTable?

Most components except can render HTML text. A header in a JTable is one of them. Try:
String header = "<html>line 1<br>line 2</html>";

Initial headers in JTable

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