Why I got position at 0? When it should be 1

Question

I learn Java, now I'm at ArrayList, I wrote some methods about banking, when I want to add a new customer at a specific branch, the position always return 0. This is the source code of the methods that I'm talking about:

The instances in Main class :

public static Scanner scanner = new Scanner(System.in);
public static Bank newBank = new Bank("BMCE");

Main class (static method to add a new customer):

public static void addNewCostumer(){
System.out.println("Choose a branch :");
String branchChoosed = scanner.nextLine();
Branches branches = newBank.queryBranch(branchChoosed);
if(branches == null){
    System.out.println("There are a problem, or you are entered a wrong name of branch");

}
else{
    System.out.println("Enter the name costumer :");
    String nameOfCostumer = scanner.nextLine();
    System.out.println("Enter the transaction number :");
    double transactions = scanner.nextDouble();
    scanner.nextLine();
    if(newBank.addNewCostumer(branches,nameOfCostumer,transactions)){
        System.out.println("The costumer was created in branch name :"+branches.getNameOfBranch());


    }else{

        System.out.println("Sorry you dindn't create a costumer in "+branches.getNameOfBranch()+" Try again please :)");

    }

}

The instances in Bank class:

private String name;
private ArrayList<Branches> branchesArrayList = new ArrayList<>();

Bank class:

public boolean addNewCostumer(Branches nameOfExistingBranch,String nameOfNewCostumer,double newTransaction){
int position = findBranch(nameOfExistingBranch);


if(position<0){
    System.out.println("There is not branch with this name");
    return false;
}
else{
    if(this.branchesArrayList.get(position).findCostumer(nameOfNewCostumer)>=0){
        System.out.println("You have already an existing costumer with that name");
        return false;
    }
    else{

        this.branchesArrayList.get(position).addNewCostumer(nameOfNewCostumer,newTransaction);
        return true;

    }

}

}

The method that finds branches:

public int findBranch(Branches branches){
int position = this.branchesArrayList.indexOf(branches);
if(position>=0){

    return position;

}
else
    return -1;
}

The inputs :

0-Mdiq
1-Casa
2-Rabat

When I add a new customer to Rabat or Casa Branch the customer always records in Mdiq (Position 0).

BTW *public int indexOf(Object o) Returns the index of the first occurrence of the specified element in this list, or -1 if this list does not contain the element. More formally, returns the lowest index i such that (o==null ? get(i)==null : o.equals(get(i))), or -1 if there is no such index.* how have you implemented `equals` — Scary Wombat, Jun 20 '19 at 00:23
My expectation is that they *haven't* overwritten `equals`. However, this means that `indexOf` does a `==` check, which is more strict — EDToaster, Jun 20 '19 at 00:33
@JClassic Agree with what you are saying, but I was banking on a badly implemented `equals` — Scary Wombat, Jun 20 '19 at 00:57
You showed us a lot of code we don't need, while failing to post the code we do need to see. As the Javadoc for [`ArrayList::indexOf`](https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/util/ArrayList.html#indexOf(java.lang.Object)) explains, your override of `Object::equals` via [`Objects.equals`](https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/util/Objects.html#compare(T,T,java.util.Comparator)) the mechanism by which the list searches for your object. Your `equals` method is likely flawed, but you don't show it so we don't know for certain. — Basil Bourque, Jun 20 '19 at 03:42
Always **search Stack Overflow** thoroughly before posting. Comparing objects for equality has been covered countless times already. — Basil Bourque, Jun 20 '19 at 03:43

score 0 · Answer 1 · edited Apr 03 '20 at 20:03

0

I' found a mistake in my code so the problem was solved. In a query method I wrote this.branchesArrayList.get(0); instead of using position as a parameter.

edited Apr 03 '20 at 20:03

TylerH

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answered Jun 21 '19 at 17:48

Abdelillah

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Why I got position at 0? When it should be 1

1 Answers1