Setting values -in a constructor- from another class

Question

I have two classes (Date and Employee).

Class Date doesn't have a constructor, but it has 3 variables with their setters.

Class Employee has a constructor where I initialized its variables. But I have to attach the 3 variables in Class Date to it.

I tried using Setter method, but when I run the code, it says that there's an error with:

hire_date.setDay(1);
hire_date.setMonth(1); 
hire_date.setYear(2018);

//In class Empolyee

 private String name;
 private Date hire_date;
 private double monthly_salary; 

    public Employee() {
        name = "Jody";
        hire_date.setDay(1);
        hire_date.setMonth(1); 
        hire_date.setYear(2018);         
        monthly_salary = 2000.0;
    }

//In class Date

 private int day;   
 private int month;
 private int year;

    public void setDay(int day) {
        this.day = day;
    }

    public void setMonth(int month) {
        this.month = month;
    }

    public void setYear(int year) {
        this.year = year;
    }

It would help if you also said *which* error you are getting... — assylias, Mar 16 '18 at 09:53
You need to initialize hire_date before calling setters of the variable. Try Date hire_date = new Date(); — chaitanya89, Mar 16 '18 at 09:56
@assylias It is ((Exception in thread "main" java.lang.NullPointerException)). I will consider this next time. — Learning Equals Success, Mar 16 '18 at 10:16

score 1 · Answer 1 · answered Mar 16 '18 at 09:56

1

There's a new Date() missing. Your Date object does not exist when you invoke the setters

answered Mar 16 '18 at 09:56

Paul Janssens

622
3
9

Thanks for the answer – Learning Equals Success Mar 16 '18 at 10:13

score 1 · Accepted Answer · answered Mar 16 '18 at 09:56

1

You have not created a Date object. Therefore, how you should be able to set its properties?

Date hire_date = new Date();

answered Mar 16 '18 at 09:56

arxakoulini

723
7
22

Thanks, it worked. – Learning Equals Success Mar 16 '18 at 10:13

score 1 · Answer 3 · answered Mar 16 '18 at 10:00

1

I run this program. Error in here is a Null Pointer exception.

Reason for it is that hire_date is not initialized. You need to add: hire_date = new Date();

before first usage of hire_date

answered Mar 16 '18 at 10:00

Przemek

126
1
6

Setting values -in a constructor- from another class

3 Answers3