Thread: Exercise 137

Alright, so as always, this is for school. Here is my exercise:

 
Exercise 137
 
    Add a customized equals method to the Car class, defined below, so that it returns true if and only if the model identification of the argument is the same as that of the Car object whose instance method is being called.
    public class Car
    {
      private String myModel,
                     myColor;
 
      public Car( String color, String model )
      {
        myColor = color;
        myModel = model;
      }
 
      public String getModel()
      { 
        return myModel;
      }

// add your equals method here

This is where my code would go.

 
    }
 
    public class MainClass
    {
      public static void main( String[] args )
      {

My code would also go here.

      }
    }
 
    What happens when your new equals method is applied to an argument that is an instance of Object or one of its subclasses, but not a Car object? Suggest a way to overcome this problem.

Alright, I feel like a jerk for posting this previously so I'm sorry, but basically, here's my question. I'm pretty sure it would return true or false. So, if it does, am I supposed to take the instance of one class and sort of poly-morph it to make it fit the instance of another class or am I just supposed to make a new class all together.

Thx, ghostheadx

Did you have a question?

Originally Posted by ghostheadx

Alright, I feel like a jerk for posting this previously so I'm sorry, but basically, here's my question. I'm pretty sure it would return true or false. So, if it does, am I supposed to take the instance of one class and sort of poly-morph it to make it fit the instance of another class or am I just supposed to make a new class all together.

It sounds like you're just supposed to add a single method (actually it sounds like the method is already there, you just have to fill in the code). The method takes a car instance as a parameter, and you have to return whether the parameter car's model is the same as the car's model for the instance you're "in" when the code is being run.

Car one = new Car("blue", "Nissan");
Car two = new Car("red", "Nissan");
Car three = new Car("black", "Monster Truck");
 
System.out.println(one.equals(two)); //prints true
System.out.println(one.equals(three)); //prints false

It's your job to define that equals method.

Please copy full text of the compiler's error message and paste it here.
The message should show the source with a ^ under the location of the error.
Here is a sample from the javac compiler:

TestSorts.java:138: cannot find symbol
symbol  : variable var
location: class TestSorts
         var = 2;
         ^