You can not change the length of an array, but you can change the values the index holds by copying new values and store them to a existing index number.
1=mike , 2=jeff // 10 = george 11 goes to 1 overwriting mike .
Object[] array = new Object[10];
int count = -1;
public void myFunction(String string) {
count++;
if(count == array.length) {
count = 0; // overwrite first
}
array[count] = string;
}