// Fig. 3.6: AdditionApplet.java
// Roy's addition Java applet

// Java core packages
import java.awt.Graphics; // import class Graphics

// Java extension packages
import javax.swing.*; // import class JApplet

public class AdditionApplet extends JApplet {
	double sum; // sum of values entered by user
	
		//initialize applet by obtaining values from user
		public void init()
		{
			String firstNumber;  // first string entered by user
			String secondNumber; // second number entered by user
			double number1;		 // first number to add
			double number2;		 // second number to add
			
			// obtain first number from user
			firstNumber = JOptionPane.showInputDialog (
				"Enter first floating point value");
			
			// obtain second number from user
			secondNumber = JOptionPane.showInputDialog (
				"Enter second floating point value");
				
			// convert numbers from type string to type double
			number1 = Double.parseDouble( firstNumber );
			number2 = Double.parseDouble( secondNumber );
			
			// add the numbers
			sum = number1 + number2;
		}
	
	// draw the results on applet's background
	public void paint ( Graphics g ) 
		{
		// call inherited version of method paint
		super.paint(g);
		
		/* draw a rectangle starting from (15, 10) that is 300
		pixels wide and 20 pixels tall */
		g.drawRect( 15, 10, 300, 20 );
				
		// draw results as a string
		g.drawString( "The sum is " + sum , 25, 25 );
				
	} // end method paint
	
} // end class AdditionApplet