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Thread: Constructor/Accessors/methods problem!!

  1. #1
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    Default Constructor/Accessors/methods problem!!

    Hi Here is my following problem:

    I have 3 fields:
    yearModel
    make
    speed

    the class is labeled Car.

    I must create a cosntructor thast accepts the cars year model and make as arguments. these values should be asssigned to the objects yearModel and make fields. the constructor should also assign 0 to the speed field.

    I must create get methods that get the values stored in yearmodel make and speed fields

    i must create an accelerate method that should add 5 to the speed each time it is called

    i must also create a brake method that will minus 5 to the speed each time it is called

    I must demonstrate this class in a program that calls the accelerate method 5 times. after each time it is called i must get the current speed and display it.

    then i must call the brake method 5 times and after each time it is called get the current speed and display it.

    I think i have the class set up correctly but not sure: I also am not quite sure how to start the program and how to execute propely. mainly how to call the methods in the program.

    package CAR_PKG;

    public class car {
    private int yearModel;
    private String make;
    private int speed;



    public car(int year, String m, int s){
    yearModel=year;
    make=m;
    speed=s;
    speed=0;

    }
    public int getyearModel()
    {
    return yearModel;
    }
    public String getmake()
    {
    return make;
    }
    public int getspeed()
    {
    return speed;
    }
    public int accelerate(int s){
    int sum=s+5;
    return sum;

    }
    public int brake(int s){
    int sub=s-5;
    return sub;
    }

    }


  2. #2
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    Cool Re: Constructor/Accessors/methods problem!!

    Why you making speed zero.

    Here is how you should call your methods
    MainClass to call your car Class

    public class MainClass {

    public static void main(String[] args) {

    car cc=new car(1990,"Maruti",55);
    //for(int i=0;i<5;i++)
    cc.accelerate();
    //for(int i=0;i<2;i++)
    cc.brake();

    System.out.println(cc);


    }

    }

    your Car class

    public class car
    {
    private int yearModel;
    private String make;
    private int speed;



    public car(int year, String m,int s)
    {
    yearModel=year;
    make=m;
    speed=s;

    }
    public int getyearModel()
    {
    return yearModel;
    }
    public String getmake()
    {
    return make;
    }
    public int getspeed()
    {
    return speed;
    }
    public int accelerate()
    {
    this.speed=speed+5;
    return speed;

    }
    public int brake()
    {
    this.speed=speed-5;
    return speed;
    }
    @Override
    public String toString() {
    return "car [Year Model= " + getyearModel() + ", Car Make= " + getmake()
    + ", Speed = " + getspeed() + "]";
    }
    }

    Here y you using another variable sum.If you changing the speed by brake n accelerator method u should use same variable to give current speed.
    I think you must not initialize speed to zero.

    Reply for more query !!!

  3. #3
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    Default Re: Constructor/Accessors/methods problem!!

    Thank you! one problem though. I am supposed to display the speed each time the accelrate method is called and each time the brake method is called

  4. #4
    Super Moderator Norm's Avatar
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    Default Re: Constructor/Accessors/methods problem!!

    Look at the how you did this: System.out.println(cc);

  5. #5
    Think of me.... Mr.777's Avatar
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    Default Re: Constructor/Accessors/methods problem!!

    1. Use the
     Your code here
    and format that properly in some editor.
    2. Make a display function that will display what do you want to and call that function in accelerate and brake function.

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