Cash implements Serializable { public Cash(int cashRegisterId) { this.cashRegisterId = cashRegisterId; this.openDate = -1; this.closeDate = -1; } Cash(int cashRegisterId);  Cash(String id, int cashRegisterId, int sequence, long openDate,
            long closeDate); String getId(); int getCashRegisterId(); int getSequence(); long getOpenDate(); boolean isOpened(); boolean wasOpened(); boolean isClosed(); long getCloseDate(); void openNow(); void closeNow(); Inventory getCloseInventory(); void setCloseInventory(Inventory i); @Override boolean equals(Object o); static Cash fromJSON(JSONObject o); JSONObject toJSON(); @Override String toString();  }
@Test public void cashTest() { assertNotNull(new Cash(1)); }