public class ProgramOne
{
// Draw an uppercase letter 'H', 12 pixels tall and 6 wide.
// Put a circle around the outside of the 'H'.
public static void main (String[ ] args)
{ Turtle sam; // create the variable named sam
sam = new Turtle(); // create the object sam refers to
sam.paint (90, 12); // draw the left side of the H
sam.move (-180, 6);
sam.paint (90, 6); // draw the crossbar of the H
sam.move (90, -6);
sam.paint (0, 12); // draw the right side of the H
sam.move (150, 6);
sam.swingAround (9); // draw a circle enclosing the H
} // this right-brace marks the end of the main method
} // this right-brace marks the end of the class
public class TwoSquares
{
// Draw two 40x40 squares side by side, 10 pixels apart.
public static void main (String[ ] args)
{ Turtle sue;
sue = new Turtle();
sue.paint (90, 40); // draw the right side of square #1
sue.paint (90, 40); // draw the top of square #1
sue.paint (90, 40); // draw the left side of square #1
sue.paint (90, 40); // draw the bottom of square #1
sue.move (0, 50); // move 50 pixels to the right
sue.paint (90, 40); // draw the right side of square #2
sue.paint (90, 40); // draw the top of square #2
sue.paint (90, 40); // draw the left side of square #2
sue.paint (90, 40); // draw the bottom of square #2
} //======================
}
public class SmartTurtle extends Turtle
{
// Make a 10x10 square; finish with the same position/heading.
public void makeSmallSquare()
{ paint (90, 10);
paint (90, 10);
paint (90, 10);
paint (90, 10);
} //======================
// Make a 40x40 square; finish with the same position/heading.
public void makeBigSquare()
{ paint (90, 40);
paint (90, 40);
paint (90, 40);
paint (90, 40);
} //======================
}
public class SquarePattern
{
// Make an X shape with one big 40x40 square in the center
// and a small 10x10 square in each corner.
public static void main (String[ ] args)
{ SmartTurtle sue;
sue = new SmartTurtle();
sue.makeBigSquare(); // draw the center square
sue.move (-90, 15); // go south
sue.move (90, 15); // move to the southeast corner
sue.makeSmallSquare(); // draw the southeast square
sue.move (90, 70); // move to the northeast corner
sue.makeSmallSquare(); // draw the northeast square
sue.move (90, 70); // move to the northwest corner
sue.makeSmallSquare(); // draw the northwest square
sue.move (90, 70); // move to the southwest corner
sue.makeSmallSquare(); // draw the southwest square
} //======================
}
public class GardenApp
{
// Draw 6 flowers all in a row, with a word title.
public static void main (String[ ] args)
{ FlowerMaker florist;
florist = new FlowerMaker();
florist.drawTwoFlowers(); // the central two
florist.sleep (300);
florist.move (0, 120);
florist.drawTwoFlowers(); // the two right of center
florist.sleep (300);
florist.move (0, -240);
florist.drawTwoFlowers(); // the two left of center
florist.sleep (300);
florist.move (40, 130);
florist.switchTo (Turtle.BLUE);
florist.say ("My flower garden"); // above the flowers
} //======================
}
public class FlowerMaker extends Turtle
{
// Draw two flowers each 60 pixels tall.
// Start and end facing east at the base of the left flower.
public void drawTwoFlowers()
{ drawFlower();
move (90, 61);
drawFlower();
move (90, -59);
} //======================
// Start facing east at the base of the flower, right side.
// End facing south at the base of the flower, center.
public void drawFlower()
{ paint (90, 50); // right side of stem
paint (90, 2);
paint (90, 50); // left side of stem
paint (90, 1);
paint (90, 10); // one-fourth of the way up the stem
paint (-45, 8); // draw the twig for the right leaf
drawLeaf();
paint (45, 10); // one-half of the way up the stem
paint (45, 8); // draw the twig for the left leaf
drawLeaf();
paint (-45, 30); // to top of stem, in the center
switchTo (RED);
fillCircle (15); // draw the flower petals
switchTo (BLACK);
move (180, 50); // return to the base of the flower
} //======================
// Draw one leaf on one flower.
public void drawLeaf()
{ switchTo (GREEN);
fillCircle (3);
move (0, 3);
fillCircle (2);
move (0, 2);
fillCircle (1);
move (0, -13);
switchTo (BLACK);
} //======================
}
public class InvestFor20
{
public static void main (String[ ] args)
{ BuyAndHoldPortfolio wealth; // 1
wealth = new BuyAndHoldPortfolio(); // 2
wealth.describeInvestmentChoices(); // 3
wealth.waitForYears (20); // 4
wealth.displayCurrentValues(); // 5
} //======================
}
public class BuyAndHoldPortfolio
{
public void describeInvestmentChoices()
{ System.out.println ("You have 5 ways to invest.");
} //======================
public void waitForYears (int years)
{ System.out.println ("Wait for your money to grow.");
} //======================
public void displayCurrentValues()
{ System.out.println ("You now have lots of money.");
} //======================
}
public class FractalApp
{
// Draw a Pythogorean tree.
public static void main (String[ ] args)
{ FractalTurtle pythagoras;
pythagoras = new FractalTurtle();
pythagoras.move (90, -240);
pythagoras.drawTree (80);
} //======================
}
public class FractalTurtle extends Turtle
{
public void drawTree (double trunk)
{ paint (0, trunk); // go to top of trunk
move (30, 0); // face to the left
if (trunk > 1)
drawTree (trunk * 0.7); // make branches on the left
move (-60, 0); // face to the right
if (trunk > 1)
drawTree (trunk * 0.7); // make branches on the right
move (30, -trunk); // go to bottom of trunk
} //======================
}
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