Java – cannot interpret NullPointerException

In the following code, I have a method to get the vector of people with the same constellation Persoane is vector < persoana > I always get a NullPointerException under the if condition (persoane is definitely not null) I can't understand why Any help would be appreciated

public Vector<Persoana> cautaDupaZodie(String zodie)
{
    Vector<Persoana> rezultat= new Vector<Persoana>();

    for(int i=0; i<persoane.size(); i++)
    {
        if(persoane.get(i).getData().getZodie().equals(zodie)) //the exception occurs here
        {
            rezultat.add(persoane.get(i));
        }

    }

    return rezultat;
}

Solution

NullPointerException occurs when you try to call a null method on an object

This means that one of the following returns null:

>Get (I) > getdata() > getzodie()

Add them one by one to find out the actual cause of the exception