Question

我创建了一些实体但我在服务器上运行时出现以下错误：

org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet（AbstractEntityManagerFactoryBean.java:318）

[spring-orm-4.1.1.RELEASE.jar：4.1.1.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods（AbstractAutowireCapableBeanFactory.java:1627） [spring-beans-4.1.1.RELEASE.jar：4.1.1.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean（AbstractAutowireCapableBeanFactory.java:1564） [spring-beans-4.1.1.RELEASE.jar：4.1.1.RELEASE] ......还有35个引起：org.hibernate.AnnotationException：@OneToOne或@ManyToOne on ..... entities.exams.answer.questionId引用一个未知实体： ..... entities.exams.question

这是实体的代码

@Entity
@Table(schema="..",name = "exam_answers")

@NamedQueries({
        @NamedQuery(name = "answer.findAll", query = "SELECT s FROM answer s"),
        @NamedQuery(name = "answer.findByanswerId", query = "SELECT s FROM answer s WHERE s.answerId = :answerId"),
        @NamedQuery(name = "answer.findByquestionId", query = "SELECT s FROM answer s WHERE s.questionId = :questionId"),
        @NamedQuery(name = "answer.findByanswer", query = "SELECT s FROM answer s WHERE s.answer = :answer") })
@Cache(usage = CacheConcurrencyStrategy.TRANSACTIONAL, region = "exams")
public class answer implements Serializable {
    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue(strategy = Generationquestion.IDENTITY)
    @Basic(optional = false)
    @Column(name = "answer_id")
    private Integer answerId;
    @JoinColumn(name = "question_id")
    @ManyToOne(optional = false)
    private question questionId;
    @JoinColumn(name = "exam_id", referencedColumnName = "exam_id")
    @ManyToOne(optional = false)
    private exam examId;
    @Size(max = 500)
    @Column(name = "answer")
    private String answer;

    public answer() {
    }

    public answer(Integer answerId) {
        this.answerId = answerId;
    }

...SETTERS AND GETTERS... 
}


@Entity
@Table(schema="..",name = "question")
@NamedQueries({
    @NamedQuery(name = "question.findAll", query = "SELECT s FROM question s"),
    @NamedQuery(name = "question.findByquestionId", query = "SELECT s FROM question s WHERE s.questionId = :questionId"),
    @NamedQuery(name = "question.findByLabel", query = "SELECT s FROM question s WHERE s.label = :label"),
    @NamedQuery(name = "question.findByquestion", query = "SELECT s FROM question s WHERE s.question = :question"),
    @NamedQuery(name = "question.findByInputquestion", query = "SELECT s FROM question s WHERE s.inputquestion = :inputquestion"),
    @NamedQuery(name = "question.findByOptions", query = "SELECT s FROM question s WHERE s.options = :options")})
public class question implements Serializable {
    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue(strategy = Generationquestion.IDENTITY)
    @Basic(optional = false)
    @Column(name = "question_id")
    private Integer questionId;
    @Basic(optional = false)
    @NotNull
    @Size(min = 1, max = 500)
    @Column(name = "label")
    private String label;
    @Basic(optional = false)
    @NotNull
    @Size(min = 1, max = 20)
    @Column(name = "question")
    private String question;
    @Size(max = 50)
    @Column(name = "input_question")
    private String inputquestion;
    @Size(max = 500)
    @Column(name = "options")
    private String options;

    public question() {
    }

    public question(Integer questionId) {
        this.questionId = questionId;
    }

Answer 1

以下是错误原因

Caused by: org.hibernate.AnnotationException: @OneToOne or @ManyToOne on
.....entities.exams.answer.questionId references an unknown entity:     
.....entities.exams.question

您是否已将entities.exams.question添加到hibernate配置？

还有几点：

在java中，类应以大写字母开头。它们应该被称为问答而不是问题和答案
在您的答案课程中，该属性不应被称为questionId，因为这会令人困惑。单词id应该只用于Long / Integer属性（可能偶尔使用String）

@OneToOne或@ManyToOne错误

1 个答案: