Ch. 6 Review Assignment (Cars)

You are to create a class called Car that will allow you to display and manipulate car objects. The Car class will contain fields as shown below in the beginnings of the class:

class Car
{
   int x; // x coordinate of the top left of the car's rectangle
   int y; // y coordinate of the top left of the car's rectangle
   color colour; // the car's rectangle's colour
   int dir; // 1 means the car is travelling horizontally to the right
            // -1 means to the left, 2 means vertically down
            // -2 means vertically up
   boolean crashed; // determines whether the car is crashed or not
 

1. Write a constructor method with no parameters that will create a red car at location (0, 0). The car will not be crashed. It will be moving to the right.
2. Write a constructor method that has 2 parameters representing the x and y location of the car. The constructor should replace any negative parameters with zero. The rest of the fields will be set as in the previous constructor.
3. Write a constructor method that has 3 parameters representing the x and y location of the car and its colour. The constructor should replace any negative coordinates with zero. The rest of the fields will be set as in the previous constructor.
4. Write a constructor method that has 5 parameters representing all fields. The order of the parameters should be the same order the fields were given in the class definition. The constructor should replace any negative coordinates with zero. If the direction is anything other than 1, -1, 2 or -2 replace it with zero.
5. Write a toString method for the Car class. For the car at coordinates (40, 65), moving up and not crashed, it should return the String (without the quotes)

    "(40, 65) dir=-2 crashed:false"

6. Write an instance method display, that draws the car. A car will be a filled rectangle 100 pixels wide by 50 pixels high with two filled black circles for wheels. The wheels should half overlap the rectangle. The rectangle should be the colour given by the colour field with a location given by the appropriate fields. A crashed car will have an X on top of it. Here is an example with two car objects created by:
   

   Car c1 = new Car();
   c1.display();
   Car c2 = new Car(200, 200, #FFFF00, 2, true);
   c2.display(); 

   

7. Write an instance method move, that will adjust the car's coordinates (if it is not crashed) 1 pixel in the direction indicated by the dir field. If the car touches the boundary of the output window it should change the dir field so the car will start moving in the opposite direction. After the coordinates have been adjusted, call the display() method. If the car is crashed, do not change the coordinates.
8. Write an instance method collidingWith, that has one Car parameter. The method should check to see if the explicit Car parameter is intersecting at all with the implicit parameter. If the two cars are touching then both cars should have their crashed fields set to true. Then call both car's display() method.
9. Write an instance method equals, which has one Car parameter. It will return true if the implicit parameter and the explicit parameter's colours are the same and their crash states are the same. Otherwise it will return false.

To submit your work:

	               Assignment #6 (Car):

Total Marks (if it was to be marked):
              ____	
               23

Comments & Indentation (3)   _____

Correct toString()  (2)      _____

Correct display() (3)        _____

Correct move()  (3)          _____

Correct collidingWith()  (3) _____

Correct equals() (2)         _____

Correct constructors  (4)    _____

Process Work  (3)            _____