java Hibernate/JPA：无法通过反射设置器设置字段值
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Hibernate/JPA: could not set a field value by reflection setter
提问by George Armhold
My JPA/Hibernate odyssey continues...
我的 JPA/Hibernate 奥德赛继续......
I am trying to work around this issue, and so I have had to define primitive @Ids in my class that uses 3 entity fields as a composite key. This seems to get me a bit further, but now I'm getting this when persisting:
我正在尝试解决这个问题，因此我不得不在使用 3 个实体字段作为复合键的类中定义原始 @Ids。这似乎让我更进一步，但现在我在坚持时得到了这个：
javax.persistence.PersistenceException: org.hibernate.PropertyAccessException: could not set a field value by reflection setter of com.example.model.LanguageSkill.stafferId
Here's my composite class:
这是我的复合类：
public class LanguageSkill implements Serializable
{
@Id
@GeneratedValue (strategy = GenerationType.IDENTITY)
@Column(name = "Staffer_ID")
private Long stafferId;
@Id
@ManyToOne(cascade = CascadeType.ALL)
@MapsId(value = "stafferId")
private Staffer staffer;
@Id
@GeneratedValue (strategy = GenerationType.IDENTITY)
@Column(name = "Language_ID")
private Long languageId;
@ManyToOne
@MapsId(value= "languageId")
private Language language;
@Id
@GeneratedValue (strategy = GenerationType.IDENTITY)
@Column(name = "Language_Proficiency_ID")
private Long languageProficiencyId;
@ManyToOne
@MapsId(value= "languageProficiencyId")
private LanguageProficiency languageProficiency;
}
I do have proper getters and setters (IDE-generated) for both the primitives as well as the entities.
对于原语和实体，我确实有适当的 getter 和 setter（IDE 生成的）。
Here are my libs. I'm not totally convinced that I'm using a compatible set of persistence libraries (references to a cookbook detailing how to properly mix-and-match these would be highly appreciated.)
这是我的库。我并不完全相信我正在使用一组兼容的持久性库（对详细介绍如何正确混合和匹配这些的食谱的参考将受到高度赞赏。）
- Hibernate 3.5.6-SNAPSHOT
- hibernate-jpamodelgen 1.1.0.CR1
- hibernate-validator 3.1.0.GA
- MySQL 5.1.6
- jsr250-api 1.0
- javax.validation validation-api 1.0.0.GA
- Hibernate 3.5.6-快照
- 休眠-jpamodelgen 1.1.0.CR1
- 休眠验证器 3.1.0.GA
- MySQL 5.1.6
- jsr250-api 1.0
- javax.validation 验证-api 1.0.0.GA
Wow, it's frustrating. 3 days now full time trying to solve various issues like this just for basic ORM. I feel defective. :-(
哇，这令人沮丧。现在 3 天全职尝试解决诸如此类的各种问题，仅适用于基本的 ORM。我觉得有缺陷。:-(
回答by Rafael Ruiz Tabares
It seems a correct code. I had problem with this exception when I used Blob[]
这似乎是一个正确的代码。我在使用 Blob[] 时遇到了这个异常问题
@Lob
@Column(name="DOCUMENTO",nullable=false)
private Blob[] documento;
But changing by Byte[], I solved this problem.
但是通过Byte[]改变，我解决了这个问题。
I have only a occurrence, looking Oracle data types, I have seen this LONG is Character data of variable length (A bigger version the VARCHAR2 datatype).
我只有一次出现，查看 Oracle 数据类型，我看到这个LONG 是可变长度的字符数据（VARCHAR2 数据类型的更大版本）。
I assume that your ID is a Integer....Why not change Long by Integer? You must remember that it only accepts primitive types.
我假设您的 ID 是一个整数....为什么不按整数更改 Long？你必须记住它只接受原始类型。
This is my code and it works fine:
这是我的代码，它工作正常：
@Id
@SequenceGenerator(sequenceName="SQ_DOCUMENTO",name="seqDocumento")
@GeneratedValue(strategy=GenerationType.SEQUENCE,generator="seqDocumento")
private Integer idDocumento;
I use Hibernate 3.5.6-final, Spring 3.0.4, Junit 4 and Oracle 11g.
我使用 Hibernate 3.5.6-final、Spring 3.0.4、Junit 4 和 Oracle 11g。
回答by Flavio Troia
You have to remove the @GeneratedValueannotations.
您必须删除@GeneratedValue注释。
