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Start your free trialErnest Lin
2,691 PointsHow do you make a constructor?
How do you make a constructor? I still don't get this...
2 Answers
Kristian Gausel
14,661 PointsThe constructor of a class named ClassExample will look like this:
public ClassExample (){
}
Where you can have arguments inside the parenthesis as with any other method.
Daniel Maia
6,228 PointsKristian is correct, a simple empty default constructor is created as per above.
However, when you create a class, you can think of a car, as an example. So, the questions you should ask yourself are:
- Make of the car?
- Model of the car?
- Number of doors?
- Color of the car? etc.
Now this may look something like this:
public class BMW {
public String mMake;
public String mModel;
public int mNumberOfDoors;
public String mColor;
// The Contructor will be used when the class is initiated
public Car(String make, String Model, int doors, String color) {
mMake = make;
mModel = model;
mNumberOfDoors = doors;
mColor = color;
}
// Below you would of the rest the code such as setters and getters etc.
......
}
As you can see above the constructor would be the first thing created when you create the Car object. Now if I was to create this class it may look something like this:
Car myNewCar = new Car("BMW", "Z4", 3, "Silver");
Now the myNewCar object will contain the properties of BMW, Z4, 3 and SIlver to which can then be used later on for other things.
I hope this is clear, if you have any questions let me know.