What does 'arrayindexoutofboundsexception' mean in java?

This exception is thrown to indicate that an array has been accessed with an illegal index. The index is either negative or greater than or equal to the size of the array. Example:

int[] arr = {1, 2, 3};
int value = arr[3];

Solution:

int[] arr = {1, 2, 3};
if(index >= 0 && index < arr.length) {
    int value = arr[index];
}

Always ensure that the array index you are accessing is within the valid range.