qbit/core/src/main/java/io/advantageous/qbit/service/stats/StatList.java
@Override
    public Long set(int index, Long element) {
        long oldValue = values[index];
        values[index] = element;
        return oldValue;
    }
@Override
    public Long set(int index, Long element) {
        long oldValue = values[index];
        values[index] = element;
        return oldValue;
    }
Set a value in the list.

@param index   index
@param element new value
@return old value at this index