在我不确定要更改哪个字段的情况下，如何使用休眠更新？

Question

  public User updateUser(User user) {

    try {
        User result = session.get(User.class, user.getId());
        if (result == null) {
            throw new FilamentNoSuchRecordException(new CoreError(304, "User does not exist"));
        }
        session.clear();
        session.update(user);

        return user;
    } catch (HibernateException e) {
        e.printStackTrace();
    }
    throw new FilamentDataConnectivityException(new CoreError(305,"Connectivity issue. Please see System Administrator"));
}

客户型号如下

 @Entity
 @Table(name = "customers")
@JsonIdentityInfo(generator=ObjectIdGenerators.PropertyGenerator.class, property="id")
 @DynamicUpdate(value=true)
 @SelectBeforeUpdate(value=true) 
 @SQLDelete(sql="Update customers SET deleted = true where customer_id=?")
 @Where(clause="deleted != true")
 @ApiModel(description="Create or update Customers")
 @JsonIgnoreProperties({"hibernateLazyInitializer", "handler"})
 public class Customer {

 @Id
 @Column(name="customer_id")
 @NotNull
 @GeneratedValue(strategy=GenerationType.AUTO)
 private int id = 0;

@Column(name="name")
@ApiModelProperty(value="The name of the customer", example="Mr J. Bond")
@NotNull
private String name;

@Column(name="description")
@ApiModelProperty(value="Desciption of the customer")
@NotNull
private String description;

@Column(name="logo_url")
@ApiModelProperty(value="Logo of user")
@NotNull
private String logo;

@Column(name="created_at")
@ApiModelProperty(value="The date the item was created", example="")
@NotNull
private Date createdAt;

@Column(name="updated_at")
@ApiModelProperty(value="The date the item was updated", example="")
@NotNull
private Date updatedAt;

@ApiModelProperty(hidden=true)
@OneToMany(fetch = FetchType.LAZY, mappedBy = "customer")
private Set<Application> applications = new HashSet<Application>();

@ManyToMany(mappedBy = "customers")
private Set<Service> services = new HashSet<Service>();

@ApiModelProperty(hidden=true)
@OneToMany(fetch = FetchType.LAZY, mappedBy = "customer")
private Set<User> users = new HashSet<User>();

@ManyToMany(cascade = CascadeType.ALL)
@JoinTable(
        name = "customer_subscription",
        joinColumns = @JoinColumn(name = "customer_id"),
        inverseJoinColumns = @JoinColumn(name = "subscription_id")
)
private Set<Subscription> subscriptions = new HashSet<Subscription>();

@ApiModelProperty(hidden=true)
@OneToMany(fetch = FetchType.LAZY, mappedBy = "customer")
private Set<Corpus> corpus = new HashSet<Corpus>();

@Column(name="deleted")
@NotNull
private boolean deleteFlag;

public int getId() {
    return id;
}

public void setId(int id) {
    this.id = id;
}

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}

public Set<Application> getApplications() {
    return applications;
}

public void setApplications(Set<Application> applications) {
    this.applications = applications;
}

public String getDescription() {
    return description;
}

public void setDescription(String description) {
    this.description = description;
}

public String getLogo() {
    return logo;
}

public void setLogo(String logo) {
    this.logo = logo;
}

public Date getCreatedAt() {
    return createdAt;
}

public void setCreatedAt(Date createdAt) {
    this.createdAt = createdAt;
}

public Date getUpdatedAt() {
    return updatedAt;
}

public void setUpdatedAt(Date updatedAt) {
    this.updatedAt = updatedAt;
}

public Set<Service> getServices() {
    return services;
}

public void setServices(Set<Service> services) {
    this.services = services;
}

public Set<User> getUsers() {
    return users;
}

public void setUsers(Set<User> users) {
    this.users = users;
}

public Set<Corpus> getCorpus() {
    return corpus;
}

public void setCorpus(Set<Corpus> corpus) {
    this.corpus = corpus;
}

public Set<Subscription> getSubscriptions() {
    return subscriptions;
}

public void setSubscriptions(Set<Subscription> subscriptions) {
    this.subscriptions = subscriptions;
}

public boolean getDeleteFlag() {
    return deleteFlag;
}

public void setDeleteFlag(boolean deleteFlag) {
    this.deleteFlag = deleteFlag;
}

}

我检查对象是否存在于数据库中，然后使用对象进行更新，例如，除了 ID 和需要更新的字段外，所有字段都可以为空。模型中的所有字段都设置为@NotNull，我正在使用@DynamicUpdate(value=true) 和@SelectBeforeUpdate(value=true) 注释，但这些似乎什么都不做。

只是失败说空字段不能为空。如何更新行？

Answer 1

正如我们在上面的评论中所讨论的那样，试试这个 -

public User updateUser(User user) {

    try {
        User result = session.get(User.class, user.getId());
        if (result == null) {
            throw new FilamentNoSuchRecordException(new CoreError(304, "User does not exist"));
        }
        result.setName(user.getName()); // update some properties
        session.update(result); // you should update 'result', not 'user'

        return result;
    } catch (HibernateException e) {
        e.printStackTrace();
        throw new FilamentDataConnectivityException(new CoreError(305,"Connectivity issue. Please see System Administrator"));
    }

}

Answer 2

通过使用我在另一个堆栈溢出中发现的这个方法post解决了这个问题。这将检查每个字段并使用 'not null' 值。然后我可以从一个只更改了 1 个字段的对象进行更新。

public static <T> T getNotNull(T a, T b) {
    return b != null && a != null && !a.equals(b) ? a : b;
}

在我不确定要更改哪个字段的情况下，如何使用休眠更新？

How do I use update using hibernate where i am not sure on which field is to be altered?

java

hibernate

hibernate-annotations