Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 9

Question

public class ItemTable {
private final Integer[] idT = { 1,2,3,4,5,6,7,8,9,10 };
private final Integer[] quantityT = { 1,2,3,4,5,6,7,8,9,10 };

private final String[] barcodeT = { "001" , "002", "003", "004", "005",null,null,null,null,null, };
private final String[] nameT =  { "Milk", "Bread", "Wine", "Butter", "Potato", "Sweet Potato","Ginger" ,"Avacado", "Cucumber"};
private final double[] perWeightT = {0.2,0.4,0.1,0.2,0.1,2,1,0.5,0,0,0};
private final double[] perPriceT = { 1.50, 2.45, 12.95, 4.75, 2, 3.5, 12, 4, 3, 1 };

private final ArrayList<ItemType> table = new ArrayList<>();
public final ArrayList<View> lookUpItem = new ArrayList<>();

public ItemTable()
{
    for(int i = 0; i< idT.length; i++)
    {
        if(barcodeT[i]!=null)
            table.add(new ItemTypeB (idT[i], nameT[i], perPriceT[i],perWeightT[i],barcodeT[i]));
        else 
        {   
            if(perWeightT[i]!=0)
            {    
                table.add( new ItemTypeW(idT[i], nameT[i], perPriceT[i],perWeightT[i],perWeightT[i]));
                lookUpItem.add( new View(idT[i], nameT[i], "w"));
            }
            if(perWeightT[i]==0) 
            {
                table.add( new ItemTypeC(idT[i], nameT[i], perPriceT[i],perWeightT[i], quantityT[i] ));
                lookUpItem.add( new View(idT[i], nameT[i], "c"));
            }
        }

    }

}

The problem area is specifically at table.add(new ItemTypeC) around the last line of code.

Hint: how many elements are in table over each you are iterating, and how many elements are in rest of tables which you are using in each iteration? — Pshemo, Aug 14 '16 at 06:03
There is no need to put `please help` around your question - it just sounds like begging. This is especially the case in the title - please keep your titles informative and succinct. Thanks! — halfer, Aug 14 '16 at 09:10

score 1 · Answer 1 · answered Aug 14 '16 at 06:02

1

Your nameT array has only 9 elements. That breaks your code.

When i= 10 at if(perWeightT[i]==0) your code throws ArrayOutofBound error

answered Aug 14 '16 at 06:02

printfmyname

983
15
30

Your first sentence is right but explanation is bit off. `i` can't be 10 inside loop because it will not pass `for` condition `i< idT.length` since `idT.length=10`. – Pshemo Aug 14 '16 at 06:09

GhostCat · Accepted Answer · 2016-08-14T06:07:23.450

One of your arrays (nameT) is "one-off"; meaning: all your arrays have 10 elements, but that has only 9 members.

But the actual problem is of a different nature: you are doing something very wrong here. Your program is written in "procedural" style.

Meaning: you have various elements that "together" form something meaningful. Your implementation: put each of those elements into its own array; and fetch the values from each array to "build" the thing that they are supposed to mean "together". So the thing that constitutes your "entity" ... is just the index within 5 different arrays.

In an Object Oriented approach, you create abstraction. Like a class Product, which has a variety of properties; such as "id", "quantity", "name" and so on. This also allows you to create reasonable equals methods to easily figure if two products are the same. And when you have created such a class; then you create one array of such objects.

Long story short: programming in Java is about finding and creating good abstractions. If you don't do that ... you run exactly in such kind of low-level problems.

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 9

2 Answers2