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JTable convert all values (ints, longs etc) to String

I have a function that makes a TableModel and I'm working on something to copy the selected cell to the clipboard but the problem is let's say a table has a structure like this:
id|name
1 |shiv
I can copy the shiv correctly because it is a string but I can't copy the ID because it isn't a string.
The function to make the TableModel is as follows:
public static DefaultTableModel buildTableModel(ResultSet rs)
throws SQLException {
ResultSetMetaData metaData = rs.getMetaData();
Vector<String> columnNames = new Vector<String>();
int columnCount = metaData.getColumnCount();
for (int column = 1; column <= columnCount; column++) {
columnNames.add(metaData.getColumnName(column));
}
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);
}
What should I change in it so that it works with all fields?

table.getModel().getValueAt(row_index, col_index);
This will return selected element as object. If you want to convert it to int you need to parse.
int i = (Integer) object;
If it is long value
Long a = (Long)object;

Refreshing JTable data using JcomboBox items coming from Access Database

How i refresh the JTable ?
Here is my Code.
public void itemStateChanged(ItemEvent evt)
{
String text=(String)to_Cmb2.getSelectedItem();
try
{
// Connect to an Access Database
Connection con=DriverManager.getConnection("jdbc:odbc:flightdsn");
Statement s=con.createStatement();
// Read data from a table
ResultSet rs = s.executeQuery("SELECT FlightNo,City,To,Arrives,Departs FROM I_Flights_Routes WHERE To ='"+text+"' ");
ResultSetMetaData md = rs.getMetaData();
int columns = md.getColumnCount();
// Get column names
for (int i = 1; i <= columns; i++)
{
columnNames.addElement(md.getColumnName(i));
}
// Get row data
while (rs.next())
{
Vector<Object> row = new Vector<>(columns);
for (int i = 1; i <= columns; i++)
{
row.addElement(rs.getObject(i));
}
data.addElement(row);
}
rs.close();
s.close();
con.close();
}
catch (Exception e)
{
System.out.println(e);
}
// Create table with database data
JTable table = new JTable(data, columnNames)
{
public Class getColumnClass(int column)
{
for (int row = 0; row < getRowCount(); row++)
{
Object o = getValueAt(row, column);
if (o != null)
{
return o.getClass();
}
}
return Object.class;
}
};
JScrollPane scrollPane = new JScrollPane(table);
scrollPane.setBounds(50,10,400,200);
td.add(scrollPane);
// td is Jpanel object
td.setVisible(true);
}

You're creating an entirely new JTable -- don't do that. Use the same JTable but
modify the JTable's model if you want to add new data to existing data
or if you want to totally replace the data in the table, create a new DefaultTableModel (or other TableModel) and set your JTable's model with it via `setModel(...).
Also, as an aside you will want to avoid using null layouts and setBounds(...) as this creates very inflexible GUI's that look terrible on other platforms or other resolutions and are very difficult to upgrade and manage.

How to display column name and set scrollbar to jtable?

connection = DriverManager.getConnection(URL, USER, PASSWORD);
Statement st = connection.createStatement();
ResultSet result = st.executeQuery("select * from department");
table_1.setModel(buildTableModel(result));
method:
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);
}
result:

You need to wrap your JTable inside a JScrollPane, and add the resulting JScrollPane to your layout.
The sample code you provided does not show how you're adding the JTable to the JPanel or JFrame of your application.

Found a solution:
I put a JScrollPane in jframe then use following code:
connection = DriverManager.getConnection(URL, USER, PASSWORD);
Statement st = connection.createStatement();
ResultSet result = st.executeQuery("select * from department");
JTable t=new JTable();
t.setModel(buildTableModel(result));
s1.setViewportView(t);
s1 is JScrollPane.
Output:

Unable to display header for jTable

These are my codes for my jTable in java swing.
private JTable getJTable() {
if (jTable == null) {
Vector columnNames = new Vector(); //Vector class allows dynamic array of objects
Vector data = new Vector();
JPanel panel = new JPanel();
panel.setSize(new Dimension(198, 106));
try {
DBController db = new DBController();
db.setUp("IT Innovation Project");
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver").newInstance();
String dsn = "IT Innovation Project";
String s = "jdbc:odbc:" + dsn;
Connection con = DriverManager.getConnection(s, "", "");
String sql = "Select * from forumTopics";
java.sql.Statement statement = con.createStatement();
ResultSet resultSet = statement.executeQuery(sql);
ResultSetMetaData metaData = resultSet.getMetaData();
int columns = metaData.getColumnCount();
for (int i = 1; i <= columns; i++) {
columnNames.addElement(metaData.getColumnName(i));
}
while (resultSet.next()) {
Vector row = new Vector(columns);
for (int i = 1; i <= columns; i++) {
row.addElement(resultSet.getObject(i));
}
data.addElement(row);
}
resultSet.close();
((Connection) statement).close();
} catch (Exception e) {
System.out.println(e);
}
jTable = new JTable(data, columnNames);
TableColumn column;
for (int i = 0; i < jTable.getColumnCount(); i++) {
column = jTable.getColumnModel().getColumn(i);
column.setMaxWidth(250);
}
String header[] = {"description", "title", "category", "posted by"};
for(int i=0;i<jTable.getColumnCount();i++) {
TableColumn column1 = jTable.getTableHeader().getColumnModel().getColumn(i);
column1.setHeaderValue(header[i]);
}
jTable.setBounds(new Rectangle(82, 218, 736, 292));
jTable.setEnabled(false);
jTable.setRowHeight(50);
jTable.getRowHeight();
}
return jTable;
}
I set an array for the header of my table. However, the program only shows the data inside my database without any header. Can somebody please enlighten me? Thanks in advance.

Put your JTable in JScrollPane like
add(new JScrollPane( getJTable() ) );

JTable swing import database sql

Could someone provide me with an example or tutorial on how to import a data from a mysql database within a JTable within the use of a GUI. I tried looking for an example but have not found anything.

Hopefully we can put this question to rest
Connection db = DriverManager.getConnection( jdbc:mysql://192.168.0.3:3306,<user>,<password>);
Statement stmt = db.createStatement();
PreparedStatement psmt = con.prepareStatement("SELECT * FROM DB");
ResultSet rs = psmt.executeQuery();
// get column names
int len = rs.getMetaData().getColumnCount();
Vector cols= new Vector(len);
for(int i=1; i<=len; i++) // Note starting at 1
cols.add(rs.getMetaData().getColumnName(i));
// Add Data
Vector data = new Vector();
while(rs.next())
{
Vector row; = new Vector(len);
for(int i=1; i<=len; i++)
{
row.add(rs.getString(i));
}
data.add(row);
}
// Now create the table
JTable table = new JTable(data, cols);