public int getCount(int prevStep) {
        prevStep = prevStep % this.slotCount;
        int index = (this.index + this.slotCount - prevStep) % this.slotCount;
        return this.data[index].intValue();
    }
@Test
    void testGetCount() {
        SimpleFlowData simpleFlowData = new SimpleFlowData(5, 10000);
        simpleFlowData.addAndGet(2);
        simpleFlowData.rotateSlot();
        simpleFlowData.addAndGet(3);
        simpleFlowData.rotateSlot();
        simpleFlowData.incrementAndGet();
        assertEquals("0 0 2 3 1", simpleFlowData.getSlotInfo());
        assertEquals(2, simpleFlowData.getCount(2));
    }