返回私有静态变量

Question

I am having trouble returning my static private variable personCount. This variable simply counts the amount of people i add into my program, in my constructor for Person i set it so every time a person was entered, personCount incremented by 1. I have also created a getPersonCount method which simply returns the int value of personCount.

My problem is that when trying to implement this method in my test file, I am unsure on how to call the method, and get the value of personCount logged to the output.

I'm not sure if i am a million miles away or a small syntax error away, so any help would be much appreciated!

My Person constructor:

public Person(String foreName, String surName, int age,
        double height, String gender)
{
    this.foreName = foreName;
    this.surName = surName;
    this.age = age;
    this.height = height;
    this.gender = gender;

    personCount = personCount +1;
} 

My getPersonCount method:

public int getPersonCount()
        {
            return personCount;
        }

My attempt to call the method in my test drive:

    System.out.println(getPersonCount());

Please let me know if any more code is needed.

Answer 1

Try this, make your method definition in class Person like:

public static int getPersonCount() { //<-- note the static modifier
   return personCount;
}

To invoke it:

System.out.println(Person.getPersonCount());//<-- use class name, if your using this method outside the class

Answer 2

You have two choices:

public static int getPersonCount() { 
   return personCount;
}

with the corresponding call:

Person.getPersonCount();

OR :

public int getPersonCount() { 
   return personCount;
}

and the corresponding call:

myPersonInstance.getPersonCount();

So in the last case, you deal with a Person instance.

Answer 3

public static int getPersonCount(){
      return personCount;
}

Then invoke above method

Person.getPersonCount();