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[英]Hibernate OGM with Mongodb Result of 2nd Query on same table dependent on Result fields of 1st query of same table
[英]Hibernate Ogm 2nd query based on 1st query result and also can't get mapped object fields(other than id) after update
我在Mongodb(3.6)中使用Hibernate OGM(5.2.0.Alpha1)
@Entity
@Table(name = "currency_master)
@JsonInclude(Include.NON_EMPTY)
public class CurrencyMaster{
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@JsonSerialize(using = ToStringSerializer.class)
@Column(name = "CURRENCY_ID", unique = true, nullable = false)
private ObjectId id;
private String code;
@OneToMany(mappedBy = "currencyMaster")
private Set<PurchaseOrder> setOfPurchaseOrder;
getter()
setter()
}
@Entity
@Table(name = "purchase_order)
@JsonInclude(Include.NON_EMPTY)
public class PurchaseOrder {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@JsonSerialize(using = ToStringSerializer.class)
@Column(name = "PURCHASE_ORDER_ID", unique = true, nullable = false)
private ObjectId id;
private String purchaseOrderNo;
private Double total;
@ManyToOne
@JsonIgnore
private CurrencyMaster currencyMaster;
getter()
setter()
}
DAO層:
@SuppressWarnings("unchecked")
@Override
public <T> void update(T t) {
try {
Field[] fields = t.getClass().getDeclaredFields();
Map<String, Object> mapUpdatedFields = new HashMap<String, Object>();
for (Field field : fields) {
field.setAccessible(true);
mapUpdatedFields.put(field.getName(), field.get(t));
}
T newT = this.getById(mapUpdatedFields.get("id").toString(), t);
mapUpdatedFields.remove("id");
mapUpdatedFields.forEach((k, v) -> {
if (!AccountingMethodUtils.isObjectisNullOrEmpty("update()", v)) {
AccountingMethodUtils.setValueToField(newT, k, v);
}
});
entityManager.merge(newT);
} catch (Exception e) {
e.printStackTrace();
LOGGER.error(
"update() of DAO : (Error in outer try..catch) Error in updating record of {} and Error is {}.",
t.getClass(), e);
}
}
@Override
public <T> List<T> executeQuery(String query, Integer startPosition, Integer noOfRecords, T t) {
List<T> listOfT = new ArrayList<>();
if (AccountingMethodUtils.isObjectisNullOrEmpty(startPosition, noOfRecords)) {
listOfT = entityManager.createNativeQuery(query.toString(), t.getClass()).getResultList();
} else {
listOfT = entityManager.createNativeQuery(query.toString(), t.getClass()).setFirstResult(startPosition)
.setMaxResults(noOfRecords).getResultList();
}
return AccountingMethodUtils.isListIsNullOrEmpty(listOfT) ? new ArrayList<>() : listOfT;
}
服務層:
@Override
@Transactional
public String updatePurchaseOrder(AccountingRequestBody input) {
PurchaseOrder purchaseOrder = AccountingMethodUtils.getObjectMapper().convertValue(input.getJsonOfObject(),
PurchaseOrder.class);
// Query : db.purchase_order.find( {'_id' : ObjectId("5ab88323191bb91e78f9e33d") } , { 'purchaseOrderNo' : 1, 'currencyMaster_CURRENCY_ID' : 1 , 'total' : 1 })
StringBuilder sb = new StringBuilder().append("db.").append(AccountingVariableUtils.TABLE_NAME_FOR_PURCHASE_ORDER)
.append(".find( {'_id' : ObjectId('" + purchaseOrder.getId().toString()
+ "') } , { 'purchaseOrderNo' : 1, 'currencyMaster_CURRENCY_ID' : 1 , 'total' : 1 })");
List<PurchaseOrder> poFromDB = purchaseOrderDao.executeQuery(sb.toString(), null, null, new PurchaseOrder());
if (!AccountingMethodUtils.isListIsNullOrEmpty(poFromDB)) {
System.out.println("id before update : " + poFromDB.get(0).getCurrencyMaster().getId()); // Output: 5ab8830b191bb91e78f9e221
System.out.println("code before update : " + poFromDB.get(0).getCurrencyMaster().getCode()); // Output: INR
}
purchaseOrderDao.update(purchaseOrder);
poFromDB = purchaseOrderDao.executeQuery(sb.toString(), null, null, new PurchaseOrder());
if (!AccountingMethodUtils.isListIsNullOrEmpty(poFromDB)) {
System.out.println("id after update : " + poFromDB.get(0).getCurrencyMaster().getId()); // Output: 5ab8830b191bb91e78f9e221
System.out.println("code after update : " + poFromDB.get(0).getCurrencyMaster().getCode()); // Output: null //?????????????????????
}
}
輸出:
id before update : 5ab8830b191bb91e78f9e221
code before update: INR
id after update : 5ab8830b191bb91e78f9e221
code afterupdate: null ?????????????????????
描述:
Currency Master具有與采購訂單的一對多映射(雙向)。
在服務層中
首先,我執行查詢以從采購訂單中獲取“ id,代碼,總計”,並成功獲取所有字段。
然后我更新了采購訂單。
然后我在更新后再次執行相同的查詢(從采購訂單中獲取“ id,代碼,總計”),然后我可以獲取貨幣主的ID,但無法獲取貨幣主的代碼。
我說得對嗎???
我認為問題在於您正在本機查詢中使用投影,並試圖在不檢索所有所需信息的情況下創建實體。 我將從本地查詢中刪除投影部分,僅使用:
db.purchase_order.find( {'_id' : ObjectId("5ab88323191bb91e78f9e33d") } );
發生這種情況是因為Hibernate OGM緩存了結果,因此您必須確保正確初始化實體。
或者,甚至更好的是,為什么不嘗試使用JPQL查詢呢?
PurchaseOrder order = em.createQuery( "FROM PurchaseOrder po WHERE po.id = :id", PurchaseOrder.class )
.setParameter( "id", "5ab88323191bb91e78f9e33d" )
.getSingleResult();
順便說一句,Hibernate OGM不應讓您執行此類操作,並且會在后續版本中引發異常。
最后,我建議更新到Hibernate OGM 5.3.0.Final或至少更新到5.2.0.Final(如果有任何理由要堅持使用5.2系列)。
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