import javax.swing.*;		// for JFrame, JLabel, JPanel
import java.awt.*;			// for Graphics

public class Ch13_4			// Creates a GUI multiplication table
{
	public static void main(String[] args)		// JLabel will be center-justified both horizontally and vertically
	{
		JFrame frame=new JFrame("Exercise12_1");				// establish title for JFrame
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);	// establish what to do if JFrame is closed
		frame.setSize(700,700);									// set size to something reasonable for this GUI
		MultPanel mt=new MultPanel();		// create the JPanel which will draw the multiplication table
		frame.add(mt);						// insert the JPanel into the JFrame and make the JFrame visible
		frame.setVisible(true);
	}
	
	public static class MultPanel extends JPanel
	{
		public void paintComponent(Graphics g)					// draw the parts of the multiplication table
		{
			g.setFont(new Font("Courier", Font.BOLD, 36));		// use big font for the title
			g.drawString("Multiplication Table", 100, 50);		// write the title near the top, somewhat centered
			g.setFont(new Font("Courier", Font.PLAIN, 16));		// change font size for the numbers
			for(int i=1;i<10;i++)								// output the numbers running along the top of the table (the column numbers)
				g.drawString(""+i,100+i*50, 100);
			for(int i=1;i<10;i++)								// now do each row of the table
			{
				g.drawString(""+i,100, 100+i*50);				// output the leftmost number (the row number)
				for(int j=1;j<10;j++)							// now for each column
					g.drawString(""+(i*j), 100+i*50, 100+j*50);  // compute i*j and place the number in its proper place in the table
			}							// requires a little math and experimentation to get this to print out correctly
			g.drawRect(130,130,450,450);						// surround the table with a rectangle to make it look more like a table
		}		// note:  we could add grid lines between each row and column - how would you do this?
	}
}