IndexOutOfBoundException 왜?

Question

필자는 작은 문제가 있습니다. java.lang.IndexoutOfBoundsException : 색인 : 29, 크기 : 29이 코드 오류가 발생할 때 if ((listaSwiat != null && listaSwiat.get(x) != null) || harm.get(y).getDzienTygodnia(x + 1).equals("Nd")) 라인이지만 Dunno 왜 INDER 30 ANY1은 도움이되지 않습니다.

Answer 1

It looks like you are looping over all the elements of harm.get(y).dni and inside the loop you do

if ((listaSwiat != null && listaSwiat.get(x) != null) 
|| harm.get(y).getDzienTygodnia(x + 1).equals("Nd"))

The last time through the loop x = 28 and the size is 29. But you do

harm.get(y).getDzienTygodnia(x + 1)

So you get the element at spot 29 which is out of bounds, because like the other answer stated the index starts at 0 not 1. You have to add a check here to see if you are currently at the last index before checking the next index.

Answer 2

In Java (and many other programming languages), indices start at zero, not one.

This means that, if the size is 29, the last valid index is 28, not 29.

Answer 3

Break apart the line that causes the exception so you can see exactly which call to get is failing.

boolean listaSwiatCheck = listaSwiat != null && listaSwiat.get(x) != null;
if (listaSwiatCheck || harm.get(y).getDzienTygodnia(x + 1).equals("Nd")) {
    c1.setBackgroundColor(BaseColor.RED);
}