how can i get an array to wrap around??

ex:

array String[] whatever = new String[3];

if i ask for the whatever[2] +1 I want it to give me 0 not 3
and if i ask whatever[0] - 1 i want it give me 2

if(whatever[i+1] == whatever.size())
{
    i = 0;
}

"i" represent current position in array

i get:

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 9
at dateapp.Main.main(Main.java:22)
Java Result: 1

public void test()
{
        String[]  j = new String[6];
        int i = 8;
        
       if(j[i+1].equals(j.length))
       {
            i = 0;
       }
       
       System.out.print(i);
    }

Use modulo arithmetic instead.

if ( i >= array.size() )
{
  i = i % array.size();
}

In fact, you don't even need the if-statement, just do the modulo...

i get:

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 9
at dateapp.Main.main(Main.java:22)
Java Result: 1

public void test()
{
        String[]  j = new String[6];
        int i = 8;
        
       if(j[i+1].equals(j.length))
       {
            i = 0;
       }
       
       System.out.print(i);
    }

Your error was caused because i+1 does not EQUAL j.length, but is still greater than the bounds of the array. Also, you should probably use == to compare numbers, the equals method is used to compare objects.

using the modulus method above i get:

operator >= cannot be applied to int,Array.size

Sorry, array.length will serve you better where array is the name of your array.

i got it to work, but it only works 8 now = 0, but i want 9 to =1 and 10 to = 2 and so forth. so basically i want the array to go in a loop.

So what's your code? The modulo operator should handle that for you...

if(whatever[i+1] == whatever.size())
{
    i = 0;
}

"i" represent current position in array

Ohh sorry, my mistake. This happens when you tired and want to go sleep, but before that you decide to solve this last problem.

if(i+1 == whatever.size())
{
    i = 0;
}
else if(i-1 > 0)
{
    i = whatever.size() -1;
}

you you need only current position in array "i" compared to array size or zero value

i got it to work, but it only works 8 now = 0, but i want 9 to =1 and 10 to = 2 and so forth. so basically i want the array to go in a loop.

darkagn is correct. If you're using the mod operator correctly then that is exactly the behavior you should get.

private int x = 8;
private int y =0;
while(x<array.length){

array[x]=y;

x++;
y++;
}

let me know if that is what your looking for

No, that is nothing like what he is looking for at all.

No, that is nothing like what he is looking for at all.

how he wantz element 8 in the array to equal 0 and 9=1 10=2 11=3 etc and thatz what that peice of coding i wrote does

No, he wants the index to wrap back around in a loop against a fixed-size array. A circular array iteration is what he is asking about.

Your code merely alters the elements [8] through [length-1] to count up from zero until the end of the array.

No, he wants the index to wrap back around in a loop against a fixed-size array. A circular array iteration is what he is asking about.

Your code merely alters the elements [8] through [length-1] to count up from zero until the end of the array.

okay i see sorry

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