Count number of existing objects

Question

So I'm making a die class that can create and roll a die, return the value and the size. I'm trying to figure out how to tell the program how many of them have been created so that I can have a response be different based on how many there are. IE I want the response from printDie to be Die Value: 5 if there is only one die, and Die 1 Value: 5 if there is more than one. Here's my code so far. ``` package com.catalyse.die; import java.util.Random; public class Die { // instance variables private int myDieValue; private int myDieSides; private Random myRandom; // Dice Class Constructors public Die() { this.myDieValue = 1; this.myDieSides = 4; } public Die(int numSides) { if ((numSides < 4) || (numSides > 100)) { System.out.println("Error! You cannot have more than 100 sides or less than four!"); System.exit(0); } else { myDieSides = numSides; } } // getter methods public int getDieSides() { return myDieSides; } public int getDieValue() { return myDieValue; } // setter methods private vo…

Accepted Answer

You can have static field in your class which could be incremented in the constructor always. The reason why is it should be `static` is because, `static` fields are shared by all instances of a class, thus a local copy of the field won't be created for each of the instances you create.

```
private static int counter = 0;
public Die()
{
    counter++;
    // Other stuffs
}
// Have a getter method for the counter so that you can 
// get the count of instances created at any point of time
public static int getCounter() {
    return counter;
}
```

And then you can call the above method in your calling method like this

```
void someMethodInAnotherClass() {
    int instanceCount = Die.getCounter(); // You need to call static method using the Class name
    // other stuffs.
}
```

Count number of existing objects

Solution

Problem