Turtle.java

      import java.util.*;
      import java.awt.*;

      /**
       * Class that represents a turtle which is similar to a Logo turtle.
       * This class inherts from SimpleTurtle and is for students
       * to add methods to.
       *
       * Copyright Georgia Institute of Technology 2004
       * @author Barb Ericson ericson@cc.gatech.edu
       */
      public class Turtle extends SimpleTurtle
      {
        ////////////////// constructors ///////////////////////

        /** Constructor that takes the x and y and a picture to
         * draw on
         * @param x the starting x position
         * @param y the starting y position
         * @param picture the picture to draw on
         */
        public Turtle (int x, int y, Picture picture)
        {
          // let the parent constructor handle it
          super(x,y,picture);
        }

        /** Constructor that takes the x and y and a model
         * display to draw it on
         * @param x the starting x position
         * @param y the starting y position
         * @param modelDisplayer the thing that displays the model
         */
        public Turtle (int x, int y,
                       ModelDisplay modelDisplayer)
        {
          // let the parent constructor handle it
          super(x,y,modelDisplayer);
        }

        /** Constructor that takes the model display
         * @param modelDisplay the thing that displays the model
         */
        public Turtle (ModelDisplay modelDisplay)
        {
          // let the parent constructor handle it
          super(modelDisplay);
        }

        /**
         * Constructor that takes a picture to draw on
         * @param p the picture to draw on
         */
        public Turtle (Picture p)
        {
          // let the parent constructor handle it
          super(p);
        }

        /////////////////// methods ///////////////////////


        public static void main(String[] args)
        {
          World earth = new World();
          Turtle t1 = new Turtle(earth);
          t1.forward();
        }

      } // this is the end of class Turtle, put all new methods before this