Java Spring Boot根据多个日期组合获取嵌套字段组的总和

Question

我有下面的实体结构。产品与内向外列表之间存在一对一关系，而内向外列表与内向库存之间存在多对多关系。InwardInventory有字段日期

public class Product extends ReusableFields
{

    private static final long serialVersionUID = 1L;

    @Id
    @GeneratedValue(strategy = GenerationType.SEQUENCE)
    Long productId;

    @NonNull
    @Column(name = "product_name")
    String productName;

    //more fields
}

public class InwardOutwardList extends ReusableFields
{
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    Long entryid;

    @ManyToOne(fetch = FetchType.EAGER, cascade = CascadeType.ALL)
    @JoinColumn(name = "productId", nullable = false)
    @JsonIgnoreProperties(
    { "hibernateLazyInitializer", "handler" })
    Product product;

Double quantity;
    //more fields

public class InwardInventory extends ReusableFields implements Cloneable
{

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "inwardid")
    Long inwardid;

    @JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "dd-MM-yyyy")
    @Column(nullable = false)
    @NonNull
    Date date;

    @ManyToMany(fetch = FetchType.EAGER, cascade = CascadeType.ALL)
    @JoinTable(name = "inwardinventory_entry", joinColumns =
    { @JoinColumn(name = "inwardid", referencedColumnName = "inwardid") }, inverseJoinColumns =
    { @JoinColumn(name = "entryId", referencedColumnName = "entryId") })
    Set<InwardOutwardList> inwardOutwardList = new HashSet<>();
//more fields
}

要求-我想在仪表板上显示10种产品，包括今天、本周和本月收到的向内和（向内和向外列表的和。数量）

我有两份清单

List<Product> productsForDashboard = getDashboardProducts(); //List of products to be displayed on dashboard

List<InwardInventory> inwardsInOneMonth =iiRepo.getCurrentMonthData(); //list of inward this months

现在，我想根据3种可能性（今天、本周、本月）了解groupby Inward Sinonemonth的最佳方法。我应该使用3种不同的流，还是可以在单个流或任何其他建议的方法中使用，以获得更好的性能

期待

{
"Product":"Iron",
"Inward":
{
"Daily":20,
"Weekly":30,
"Monthly":70
}
}

我使用嵌套循环编写了一个工作逻辑，但这似乎很沉重。下面是我写的逻辑

Calendar cal1 = Calendar.getInstance();
        Calendar cal2 = Calendar.getInstance();
        HashMap<Product,InventoryHistoricalStats> map = new HashMap<>();
        initializeMap(productsForDashboard,map); //add all products to map and set sum as zero
        for(Product p:productsForDashboard) {
            for(InwardInventory ii:inwardsInOneMonth){
                for(InwardOutwardList iol:ii.getInwardOutwardList()){
                    if(iol.getProduct().equals(p)){
                        InventoryHistoricalStats ihs = map.get(p);
                        cal1.setTime(ii.getDate());
                        cal2.setTime(new Date());
                        if(cal1.get(Calendar.DAY_OF_YEAR)==cal1.get(Calendar.DAY_OF_YEAR))
                            ihs.getInward().setDaily(ihs.getInward().getDaily()+iol.getQuantity());

                        if(cal1.get(Calendar.WEEK_OF_YEAR)==cal1.get(Calendar.WEEK_OF_YEAR))
                            ihs.getInward().setWeekly(ihs.getInward().getWeekly()+iol.getQuantity());

                        if(cal1.get(Calendar.MONTH)==cal1.get(Calendar.MONTH))
                            ihs.getInward().setMonthly(ihs.getInward().getMonthly()+iol.getQuantity());
                        map.replace(p,ihs);
                    }
                }
            }

                }
            }
        }
        return transformDataForDashboard(map);
    }

    private List<InventoryHistoricalStats> transformDataForDashboard(HashMap<Product, InventoryHistoricalStats> map) {
        List<InventoryHistoricalStats> returnData = new ArrayList<>();
        for(Map.Entry<Product,InventoryHistoricalStats> set:map.entrySet()){
            InventoryHistoricalStats ihs = set.getValue();
            ihs.setProductName(set.getKey().getProductName());
            ihs.setMeasurementUnit(set.getKey().getMeasurementUnit());
            returnData.add(ihs);
        }
        return returnData;
    }