Accessing an element of an object in an arraylist [closed]

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I am working with an ArrayList of objects that contain multiple variables. For example:

// pseudo code
class Ticket {    
    int gameID
    double price
    int seatnumber
}

and I have an ArrayList of multiple Ticket objects and need to access them. I've looked at the javadoc and so far I have come up with

list.get(index).attribute

However I get a compile-error saying:

cannot find symbol

am I doing something wrong with the syntax? here is my code:

public static void printGameMoney(ArrayList games, ArrayList tickets)
{
    double total = 0;
    double tickMoney = 0;

    for (int i=0; i<tickets.size(); i++)
    {           
        double tickMoney = tickets.get(i).priceOfTick;
        total = total + tickMoney;          
    }
}

Answer 1

If attribute is really one of your class member then please use as follow.

((Ticket) list.get(index)).attribute;

Answer 2

You code is "old-school", you should use typed-types, interfaces and new style for-loop:

public static void printGameMoney(final List<Game> games, final List<Ticket> tickets)
{
    double total = 0;

    for (final Ticket ticket : tickets)
    {           
        final double tickMoney = ticket.getPriceOfTick();
        total = total + tickMoney;          
    }
}

Also note this method is strange as it doesn't return anything.

Answer 3

Start by putting semicolons after each field declaration:

class Ticket {    
    int gameID;
    double price;
    int seatnumber;
}

Also, show the exact code you're using instead of list.get(index).attribute.

Answer 4

List<Object> list = new ArrayList<Object>();
((Ticket)list.get(x)).attribute;

Answer 5

Use this instead:

public static void printGameMoney(ArrayList games, ArrayList<Ticket> tickets)
{
    double total = 0;
    double tickMoney = 0;

    for (int i=0; i<tickets.size(); i++)
    {           
        double tickMoney = tickets.get(i).priceOfTick;
        total = total + tickMoney;          
    }
}

Basically, the change leads to ArrayList<Ticket> instead of simple ArrayList. This way you tell the compiler that objects inside your ArrayList are of Ticket type, therefore they have attributes you specified (e.g. priceOfTick).

Same goes for games, so if you have Game class, you should use ArrayList<Game> games.

Answer 6

You have to access like this ,list.get(i).price; not list.price.get(i);

for (int i=0; i<tickets.size(); i++)
{

    double tickMoney =  list.get(i).price;
    total = total + tickMoney;  

}

Here problem is that with your deceleration of ArrayList

If you declare like ArrayList<Ticket> you need not to cast there while getting. Other wise you need a cast there. More over use for each loop.