I did not find a similar question, this is the ref I noticed but did not help: Accessing public static java method from scala
I am confused as to why I can not access the cellPhone method addContact from the Start class? addContact is public and static. If you look at the joseph class I wanted to see the difference between array of object vs ArrayList of objects in terms of access.
I know this is perfectly organized, perhaps I should have the cellPhone class in the Joseph class? But that did not work either.
My Error is in the Start class.
Start class:
public class Start
{
public static void main(String[] args)
{
// TODO Auto-generated method stub
Joseph jhr = new Joseph();
jhr.addCreditCard("Visa");
jhr.setWeight(168);
jhr.setHairColor("Brown");
jhr.setGender("male");
jhr.setName("Randy ");
jhr.myCellPhone.addContact();//ERROR: he method addContact() is undefined for the type List<cellPhone>
jhr.cell[0].setCellPhone(5255857);
jhr.cell[1].setCellPhone(4155053);
jhr.cell[0].addContact("Bob");
jhr.cell[1].addContact("Amy");
//jhr.cell.addContact("Nameishi");
//jhr.cell.setCellPhone(3333847);
System.out.println("Single : "+jhr.showStatus() + " Gender: " + jhr.showGender() +" Name:"+jhr.showName());
//System.out.println("Cell number: " +jhr.cell.showCellNumber());
System.out.println("Middle name: " + jhr.middleName);
}
}
CellPhone class:
public class cellPhone {
private int cellPhoneNumber;
static private List<String> myContacts = new ArrayList<String>(100);
public cellPhone() {
// TODO Auto-generated constructor stub
}
//show all numbers in cell phone
public final int showCellNumber() {
return cellPhoneNumber;
}
//get all Contacts in cell Phone
public List<String> contactsList()
{
return myContacts;
}
//add numbers to cell phone
public void setCellPhone(int myNumber) {
cellPhoneNumber = myNumber;
}
//add contacts to cell phone
static public void addContact(String contact) {
myContacts.add(contact);
}
}
Joseph Class:
public class Joseph extends human
{
//public static final cellPhone cell = null;
public cellPhone [] cell = new cellPhone[2];
static public List<cellPhone> myCellPhone = new ArrayList<cellPhone>(100);
public String middleName;
private int weight;
public Joseph()
{
middleName = "John";
weight = 0;
cell[0]= new cellPhone();
cell[1]= new cellPhone();
//cell.setCellPhone(3253847);
}
public void setWeight(int setw)
{
weight = setw;
}
public int getWeight()
{
return weight;
}
}
Also, addContact() is a static method. That means the method belongs to the Class instead of the instance of the class. In other words, all CellPhone instances will share the list static private List<String> myContacts
. Remove the static before the method and before the list and it will all make sense.
I have to add a CellPhone to the list, then I have to set it. I think Arrays are easier but obviously Arraylist are dynamic. For anyone with my issue here is how I solved it.
jhr.myCellPhone.add(new cellPhone());
jhr.myCellPhone.get(0).addContact("Joseph");
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