A small problem

[Imstuck]

hey guys!

I have a small problem, it's probably easy for alot of you but I'm kind of new to Java so I would like some help.

I have class (call it 'worker') and this class has a method called "work".

I have a second class in which i have an array variable stored with 'worker' object.
However when i try to use the 'work' method on one of those objects i get the error: 'cannot find symbol - method work()'

Can someone help me?

[JosAH]

Does that method take parameters?

kind regards,

Jos

[Imstuck]

Worker class has a field named 'hours'

the method is:

public void work(int hours){
this.hours += hours;
}

In the second class this is my constructor:

public secondClass(){
Staffmember[] members = new Staffmember[4];
member[0] = new Worker("Jan", 1000);
member[1] = new Worker("Jef", 25);


this.member = member;

member[0].work(10);
member[1].werk(15);


Staffmember is a superclass of worker. This contructor creates 2 workers (a subclass of staffmember) and puts them in a arraylist.
I got it working till there.

Now i try to use the work method on one of those workers but get the mentioned error.

[JosAH]

All that the compiler knows is that the array elements are StaffMembers and Staffmembers don't have a work( ... ) method.

kind regards,

Jos

[DarrylBurke]

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[Imstuck]

JoSah yes that's most probably the problem, how do I change it though? don't i suggest it's a worker when i say member[0] = new Worker("Jan", 1000); ?

Here is the full code (it's in dutch but you'll hopefully understand)

Worker:

 public class Arbeider extends Personeelslid{
private int uurloon;
private int aantalUren;
public Arbeider(String naam, int uurloon){
super(naam);
this.uurloon = uurloon;
aantalUren = 0;

}

public void werk(int uren){
this.aantalUren += uren;
}

public int getLoon(){
int loon = 0;
loon = aantalUren * uurloon;
return loon;
}

}

Staffmembers:

 public class Personeelslid{
    public String naam;

    public Personeelslid(String naam){
        this.naam = naam;
    }

    public String getNaam(){
        return naam;
    }

    public int getLoon(){
        return 0;
    }

}

Staff code:

 public class Personeel{

    private Personeelslid[] leden;

    public Personeel(){
        Personeelslid[] leden = new Personeelslid[4];
        leden[0] = new Bediende("Jan", 1000);
        leden[1] = new Arbeider("Jef", 25);
        leden[2] = new Bediende("Jop", 1250);
        leden[3] = new Arbeider("Jeroen", 35);

        this.leden = leden;
        
        leden[1].werk(10);
        leden[3].werk(15);
        

    }

    public void betaalDag(){
        for(Personeelslid lid : leden){
            System.out.println("Naam: " + lid.naam + " ; Salaris: " + lid.getLoon());
        }
    }

}

[Fubarable]

JoSah yes that's most probably the problem, how do I change it though? don't i suggest it's a worker when i say member[0] = new Worker("Jan", 1000); ?

It may be an Arbeider object, but it's held by a Personeelslid array and thus is treated as a Personeelslid variable.

Here is the full code (it's in dutch but you'll hopefully understand)

I've got a sneaking suspicion that JosAH will understand this (for me) confusing and confounding language.

[JosAH]

I've got a sneaking suspicion that JosAH will understand this (for me) confusing and confounding language.

What's wrong with a language that sounds like clearing your throat all the time? The class hierarchy is broken. Every staff member is supposed to work so the work( ... ) method and its compadres don't belong in the Worker (Arbeider) class; they belong in the StaffMember (Personeelslid) parent class. A hackish solution o.t.o.h. would be a downcast, but I consider that, just hacking ...

kind regards,

Jos

[Fubarable]

What's wrong with a language that sounds like clearing your throat all the time?

I have problems with *all* of the Germanic languages. ... including my own!

[Imstuck]

What's wrong with a language that sounds like clearing your throat all the time? The class hierarchy is broken. Every staff member is supposed to work so the work( ... ) method and its compadres don't belong in the Worker (Arbeider) class; they belong in the StaffMember (Personeelslid) parent class. A hackish solution o.t.o.h. would be a downcast, but I consider that, just hacking ...

kind regards,

Jos

Problem is there are other subclasses with Staffmember as superclass, so work is specific for worker. :)

[JosAH]

Problem is their are other subclasses with Staffmember as superclass, so work is specific for worker. :)

Why not have an array of Worker objects then? That way you can be sure that all elements can work( ... )

kind regards,

Jos

[JosAH]

I have problems with *all* of the Germanic languages. ... including my own!

I can order two large beer from the tap in Swahili ...

kind regards,

Jos (<--- true polyglot ;-)

[Imstuck]

Why not have an array of Worker objects then? That way you can be sure that all elements can work( ... )

kind regards,

Jos

It's an assignment and the array has to be of the superclass and i have to use the subclass method. I hope someone can help, I've been thinking about this for hours and deadline is in 20 mins. :/

[JosAH]

Then use the instanceof operator together with a downcast (a hack):

if (elements[i] instanceof Worker)
   ((Worker)elements[i]).work( ... );

kind regards,

Jos