import javax.swing.*;
import java.awt.*;
public class Frame extends JFrame {

	final static String[] tab1ColName = {"Col 1", "Col 2", "Col 3"};
	final static String tab1LabelName = "This is the header of Tab 1";
	final static String[] tab2ColName = {"Col A", "Col B", "Col C", "Col D"};
	final static String tab2LabelName = "This is the header of Tab 2";
	final static String[] tab3ColName = {"First Col", "Second col"};
	final static String tab3LabelName = "This is the header of Tab 3";
	final static String[] tabName = {"Tab one", "Tab two", "Tab three"};
		

	JTabbedPane pane;
	Tab tab[];
	
	Frame() {
		super("reCoded Application");
		setLayout(new BorderLayout());
		setSize(400, 300);
		this.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
		
		JLabel label = new JLabel("This is the main header of the application");
		label.setHorizontalAlignment(SwingConstants.CENTER);
		add(label, BorderLayout.NORTH);
		
	    pane = new JTabbedPane();
	    tab = new Tab[3];
	    tab[0] = new Tab(tab1ColName, tab1LabelName);
	    pane.add(tabName[0], tab[0]);
	    tab[1] = new Tab(tab2ColName, tab2LabelName);
	    pane.add(tabName[1], tab[1]);
	    tab[2] = new Tab(tab3ColName, tab2LabelName);
	    pane.add(tabName[2], tab[2]);
	    add(pane, BorderLayout.CENTER);
	}
	
	// to do the test
	void test() {
		String[] abc = {"Col1", "Col2", "Col3", "Col4"};
		// add a row
		tab[1].addRow(abc);
		// show it
		pane.setSelectedIndex(1);
		String[] str = tab[1].getRow(0);
		System.out.println("Rows 0 of tab2 contains: ");
		for(int i = 0; i < str.length; i++)
			System.out.print(" " + str[i]);
		System.out.println();
		
	}
	public static void main(String[] arg) {
		Frame f = new Frame();
		f.setVisible(true);
		
		// ok now test
		f.test();
	}
}

import javax.swing.*;
import javax.swing.table.*;
import java.awt.*;

public class Tab extends JPanel {

	JTable table;
	DefaultTableModel model;
	
	Tab(String[] colName, String labelName) {
		super(new BorderLayout());
		add(new JLabel(labelName), BorderLayout.NORTH);
		model = new DefaultTableModel();
		for(int i = 0; i < colName.length; i++)
			model.addColumn(colName[i]);
		table = new JTable(model);
		add(new JScrollPane(table), BorderLayout.CENTER);	
	}
	
	void addRow(String[] str) {
		model.addRow(str);
	}
	
	String[] getRow(int n) {
		if(n >= model.getRowCount())
			throw new IllegalStateException("getRow for " + n + " exceeds numner of rows");
		int c = model.getColumnCount();
		String[] str = new String[c];
		for(int i = 0; i < c; i++)
			str[i] = (String) model.getValueAt(n, i);
		return str;
	}
}