Jka at 14:46, 30 March 2007

2007-03-30T14:46:53Z

Jka at 14:45, 30 March 2007

2007-03-30T14:45:43Z

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==Background==
We have discussed the class Turtle and Island in class and in Lab sessions. In this homework you will focus on getting acquainted with extending a class to add more functionality. You have been given the UMLs for the two classes in your lecture notes. Your job is to augment the Turtle class by creating a new subclass called GeometricTurtle that contains at least the following methods:

# drawSide(length: double, angle: double) draws the side of an object of the specified length, then turns the specified angle.<br>Using this drawSide method you will implement the following methods:
# rectangle(length: double, breadth: double) draws a rectangle.,
# pentagon(length: double) draws a regular pentagon,
# hexagon(length: double) draws a regular hexagon,
# octagon(length: double) draws a regular octagon,
# square(length: double) draws a regular square, and
# a driver class, DrawHouse( ), that draws the house given in the figure below.

← Older revision		Revision as of 14:46, 30 March 2007
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	# square(length: double) draws a regular square, and		# square(length: double) draws a regular square, and
	# a driver class, DrawHouse( ), that draws the house given in the figure below.		# a driver class, DrawHouse( ), that draws the house given in the figure below.
		+	==GeometricTurtle.java==
		+	<pre>
		+	public class GeometricTurtle extends Turtle {
		+	// Simple method that draws a line of length "length", then turns
		+	// to the left "angle" degrees. Note that we put the turtle's
		+	// tail down at the beginning and pick it up at the end. Since
		+	// we do it here, we don't have to worry about doing it in any
		+	// of the methods following this one that use this particular method.
		+	public void drawSide(double length, double angle) {
		+	this.tailDown();
		+	this.move(length);
		+	this.turnLeft(angle);
		+	this.tailUp();
		+	} // end drawSide
		+
		+	// Method to draw a rectangle. We will be able to use this method
		+	// again in a method after this for drawing a square, seeing as
		+	// a square is just a rectangle with equal sides.
		+	//
		+	// Input is the lenth of the two differing sides of the rectangle.
		+	public void drawRectangle(double length, double breadth) {
		+	this.drawSide(length,90); // Rectangle angles are 90 degrees (360/4)
		+	this.drawSide(breadth,90);
		+	this.drawSide(length,90);
		+	this.drawSide(breadth,90);
		+	} // End drawRectangle
		+
		+	// Method to draw a pentagon. Input is just the length of the sides
		+	// of the pentagon. If we knew about loops this code could be even
		+	// cleaner, of course.
		+	public void drawPentagon(double length) {
		+	this.drawSide(length,72); // Pentagon angles are 72 degrees (360/5)
		+	this.drawSide(length,72);
		+	this.drawSide(length,72);
		+	this.drawSide(length,72);
		+	this.drawSide(length,72);
		+	} // End drawPentagon
		+
		+	// Method to draw a hexagon. Input is the length of the sides of the
		+	// hexagon.
		+	public void drawHexagon(double length) {
		+	this.drawSide(length,60); // Hexagon angles are 60 degrees (360/6)
		+	this.drawSide(length,60);
		+	this.drawSide(length,60);
		+	this.drawSide(length,60);
		+	this.drawSide(length,60);
		+	this.drawSide(length,60);
		+	} // End drawHexagon
		+
		+	// Method to draw an octagon. Input is the length of the sides of the
		+	// octagon.
		+	public void drawOctagon(double length) {
		+	this.drawSide(length,45); // Octagon angles are 45 degrees (360/8)
		+	this.drawSide(length,45);
		+	this.drawSide(length,45);
		+	this.drawSide(length,45);
		+	this.drawSide(length,45);
		+	this.drawSide(length,45);
		+	this.drawSide(length,45);
		+	this.drawSide(length,45);
		+	} // End drawOctagon
		+
		+	// Method to draw a square. Input is the length of the sides of the
		+	// square. Note that we are using the drawRectangle method from this
		+	// method since it does exactly what we need here as well.
		+	public void drawSquare(double length) {
		+	this.drawRectangle(length,length);
		+	} // End drawSquare
		+	} // End class GeometricTurtle
		+	</pre>

CIS 3020 Project 1 - Revision history

Jka at 14:46, 30 March 2007

Jka at 14:45, 30 March 2007