Question

Please explain clearly which line means what and how can I get the answer.
(correct answer 2 2)

public class Checker 
{
    public static int count = 0;
    public int number = 0;

    public Checker(){
        count++;
        number = count;
    }

    public int getCount() { return count; }
    public int getNumber() { return number; }
}

What is output from the code fragment below?

Checker one = new Checker();
Checker two = new Checker();
System.out.println(one.getCount() + " " + two.getCount());

Answer 1

code:

class Checker
{
public static int count = 0; //static variable (common to all instatnces(or objects) of class)
public int number = 0;

public Checker(){ //constructor (executed every time object is ceated)
count++; //count increament (here value of count will increase by 1 everytime the object is craeted)
number = count; //sets number variable equal to count
}

public int getCount() { return count; } //returns the value of static variable count
public int getNumber() { return number; } //returns value of variable number
  
}
public class Main{
public static void main(String a[])
{
Checker one = new Checker(); //constructor executed(setting count=1 and number=count i.e. number=1)
Checker two = new Checker(); //again constructor executed (setting count=2 now and likewise number=count=2)
System.out.println(one.getCount() + " " + two.getCount());
//getCount here will now return value 2 since count variable is static (i.e. it is common to both objects created here)
//if getNumber used, one.getNumber=1 and two.getNumber=2 because separate copy if each variable is maintained for number variable
  
}
}