java - 在实体管理器上调用合并后实体丢失状态

Question

我遇到了一个非常烦人的问题，即实体在对象合并到 EntityManager 后会丢失其状态。

在应用程序中有一个带有 ExpenditureStatements 的“文件”，其中包含许多支出。

这些支出可以(部分)向多个债务人索偿。 为 ExpenditureStatement 创建 ExpenditureStatementClaim。 为 ExpenditureStatement 上的每项支出创建一个 ExpenditureClaim。

ExpenditureClaims 和 ExpenditureStatementClaim 均已保留，没有任何问题。 然而，在调用实体管理器上的合并后，支出会失去其状态: em.merge(文件)。

但是，每次支出中的数据都会恢复到数据库中的最后状态。

我已经尝试过自上而下的级联，我对 equals/hashcode 进行了更改，但这没有改变任何内容。

有谁知道可能导致此问题的原因吗？

文件:

@Entity
@Table(name = "DOSSIER")
@Inheritance(strategy = InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(name = "DOSSIER_TYPE", discriminatorType = DiscriminatorType.STRING, length = 48)
public abstract class Dossier  {

@OneToMany(mappedBy = ExpenditureStatement.PROP_DOSSIER, cascade = CascadeType.ALL, orphanRemoval = true, fetch = FetchType.LAZY)
private List<ExpenditureStatement> expenditureStatements = new ArrayList<ExpenditureStatement>();
}

支出明细表:

@Entity
@Table(name = "EXPENDITURE_STATEMENT")
public class ExpenditureStatement {
@ManyToOne(fetch = FetchType.LAZY, cascade = {CascadeType.MERGE})
@JoinColumn(name = "DOSSIER_ID", nullable = false)
private Dossier dossier;

@OneToMany(mappedBy = Expenditure.PROP_EXPENDITURE_STATEMENT, cascade = CascadeType.ALL, orphanRemoval = true, fetch = FetchType.EAGER)
private List<Expenditure> expenditures = new ArrayList<Expenditure>();

@OneToMany(mappedBy = ExpenditureStatementClaim.PROP_EXPENDITURE_STATEMENT, cascade = CascadeType.ALL, orphanRemoval = true, fetch = FetchType.EAGER)
private Collection<ExpenditureStatementClaim> expenditureStatementClaims = new ArrayList<ExpenditureStatementClaim>();
}

支出:

@Entity
@Table(name = "EXPENDITURE")
@Inheritance(strategy = InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(name = "EXPENDITURE_ORIGIN_CD", discriminatorType = DiscriminatorType.STRING, length = 48)
public abstract class Expenditure extends EntityObject<Long> {

@ManyToOne(fetch = FetchType.EAGER, cascade = {CascadeType.PERSIST, CascadeType.MERGE})
@JoinColumn(name = "EXPENDITURE_STATEMENT_ID", nullable = false)
private ExpenditureStatement expenditureStatement;

@OneToMany(mappedBy = ExpenditureClaim.PROP_EXPENDITURE, cascade = CascadeType.ALL, orphanRemoval = true, fetch = FetchType.EAGER)
private Collection<ExpenditureClaim> claims = new HashSet<>();

@NotNull
@Column(name = "EXPENDITURE_STATUS_CD", nullable = false)
@Enumerated(EnumType.STRING)
private ExpenditureStatus status;

public abstract BigDecimal getAmount();
}

支出声明 claim :

@Entity
@Table(name = "DEEL_STAAT")
public class ExpenditureStatementClaim {    

@NotNull
@ManyToOne(cascade = {CascadeType.MERGE, CascadeType.PERSIST})
@JoinColumn(name = "EXPENDITURE_STATEMENT_ID", nullable = false)
private ExpenditureStatement expenditureStatement;

@OneToMany(mappedBy = ExpenditureClaim.PROP_EXPENDITURE_STATEMENT_CLAIM, cascade = CascadeType.ALL, orphanRemoval = true, fetch = FetchType.EAGER)
private Collection<ExpenditureClaim> expenditureClaims = new ArrayList<>();

@ManyToOne(cascade=CascadeType.ALL)
@JoinColumn(name = "INVOICE_ID")
private Invoice invoice;
}

支出 claim :

@Entity
@Table(name = "EXPENDITURE_CLAIM")
public class ExpenditureClaim extends EntityObject<Long> {

@ManyToOne(fetch = FetchType.EAGER, cascade = {CascadeType.PERSIST, CascadeType.MERGE})
@JoinColumn(name = "EXPENDITURE_ID", nullable = false)
private Expenditure expenditure;

@Column(name = "AMOUNT", precision = NumberConstants.CURRENCY_PRECISION, scale = NumberConstants.CURRENCY_OPERATION_SCALE)
private BigDecimal amount;

@ManyToOne(fetch = FetchType.EAGER, cascade = {CascadeType.PERSIST, CascadeType.MERGE})
@JoinColumn(name = "EXPENDITURE_ST_CLAIM_ID", nullable = false)
private ExpenditureStatementClaim expenditureStatementClaim;
}

Answer 1

该问题不是由映射问题引起的，而是由于项目使用的 EclipseLink(相当旧的)版本中的错误导致，新创建的对象不会级联对现有对象所做的更改。

https://bugs.eclipse.org/bugs/show_bug.cgi?id=340802

只是一个很好的提醒，只要有可能，您就应该尝试更新项目中依赖项的版本...