How to view database resultset in Java swing

Viewing your result - JTable is your best choice

Saving the results, well, unless you want to use a 3rd part library, you options are very limited, unless your very familiar with the various file formats you want to use.

Out of the box, I'd say CVS would be easy to achieve.

JTable will do best, here is the code for display ResultSet on JTable

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));
JOptionPane.showMessageDialog(null, new JScrollPane(table)); // or can you other swing component

// Closes the Connection
}

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);

}

it would be hard to export data to pdf or rtf without using 3rd party api