array limits

[mrjoli021]

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

[peter_budo]

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

"i" represent current position in array

[mrjoli021]

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);
    }

[darkagn]

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...

[darkagn]

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.

[mrjoli021]

using the modulus method above i get:

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

[darkagn]

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

[mrjoli021]

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]

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

[peter_budo]

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

[Ezzaral]

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.

[imran786]

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

[Ezzaral]

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

[imran786]

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

[Ezzaral]

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.

[imran786]

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