ManyToMany:MappingException:无法确定：java.util.List的类型

我有一些桌子：

profile：id_profile

经验：身份证经验，身份证档案

能力水平：识别能力水平，水平

一个PROFIL可以有很多经验和很多能力水平

一个经验可以有很多能力水平

一个能力水平涉及大量的经验

因此，对我来说，在经验和能力水平之间，这是一种（n-p）

manytomy

关系

我试过：

PROFIL.java:

@Entity
@Table(name="profil")
public class Profil {

    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    @Column(name="id_profil")
    private Long idProfil;

    public Profil() {
        super();
    }

    public Long getIdProfil() {
        return idProfil;
    }

    public void setIdProfil(Long idProfil) {
        this.idProfil = idProfil;
    }

    @Override
    public String toString() {
        //[...]
    }

}

@Entity
@Table(name="experience")
public class Experience {

    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    @Column(name="id_experience")
    private Long idExperience;

    @ManyToOne
    @JoinColumn(name="id_profil")
    private Profil idProfil;

    private List<CompetenceLevel> competenceLevels;

    public Experience() {
        super();
        idProfil = new Profil();
    }

    public Long getIdExperience() {
        return idExperience;
    }

    public void setIdExperience(Long idExperience) {
        this.idExperience = idExperience;
    }

    public Profil getIdProfil() {
        return idProfil;
    }

    public void setIdProfil(Profil idProfil) {
        this.idProfil = idProfil;
    }

    @ManyToMany(cascade = CascadeType.ALL)
    @JoinTable(name = "experience_competence_level", joinColumns = @JoinColumn(name = "id_experience", referencedColumnName = "id_experience"), inverseJoinColumns = @JoinColumn(name = "id_competence_level", referencedColumnName = "id_competence_level"))
    public List<CompetenceLevel> getCompetenceLevels() {
        return competenceLevels;
    }

    public void setCompetenceLevels(List<CompetenceLevel> competenceLevels) {
        this.competenceLevels = competenceLevels;
    }

    @Override
    public String toString() {
        // [...]
    }

}

@Entity
@Table(name="competence_level")
public class CompetenceLevel {

    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    @Column(name="id_competence_level")
    private Long idCompetenceLevel;

    @OneToOne
    @JoinColumn(name="id_level")
    private Level level;

    @OneToOne
    @JoinColumn(name="id_profil")
    private Profil profil;

    private List<Experience> experiences;

    public CompetenceLevel() {
        super();
    }

    public Long getIdCompetenceLevel() {
        return idCompetenceLevel;
    }

    public void setIdCompetenceLevel(Long idCompetenceLevel) {
        this.idCompetenceLevel = idCompetenceLevel;
    }

    public Level getLevel() {
        return level;
    }

    public void setLevel(Level level) {
        this.level = level;
    }

    public Profil getProfil() {
        return profil;
    }

    public void setProfil(Profil profil) {
        this.profil = profil;
    }

    @ManyToMany(mappedBy = "competenceLevels")
    public List<Experience> getExperiences() {
        return experiences;
    }

    public void setExperiences(List<Experience> experiences) {
        this.experiences = experiences;
    }

    @Override
    public String toString() {
        // [...]
    }

}

EXPERIENCE.java:

@Entity
@Table(name="profil")
public class Profil {

    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    @Column(name="id_profil")
    private Long idProfil;

    public Profil() {
        super();
    }

    public Long getIdProfil() {
        return idProfil;
    }

    public void setIdProfil(Long idProfil) {
        this.idProfil = idProfil;
    }

    @Override
    public String toString() {
        //[...]
    }

}

@Entity
@Table(name="experience")
public class Experience {

    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    @Column(name="id_experience")
    private Long idExperience;

    @ManyToOne
    @JoinColumn(name="id_profil")
    private Profil idProfil;

    private List<CompetenceLevel> competenceLevels;

    public Experience() {
        super();
        idProfil = new Profil();
    }

    public Long getIdExperience() {
        return idExperience;
    }

    public void setIdExperience(Long idExperience) {
        this.idExperience = idExperience;
    }

    public Profil getIdProfil() {
        return idProfil;
    }

    public void setIdProfil(Profil idProfil) {
        this.idProfil = idProfil;
    }

    @ManyToMany(cascade = CascadeType.ALL)
    @JoinTable(name = "experience_competence_level", joinColumns = @JoinColumn(name = "id_experience", referencedColumnName = "id_experience"), inverseJoinColumns = @JoinColumn(name = "id_competence_level", referencedColumnName = "id_competence_level"))
    public List<CompetenceLevel> getCompetenceLevels() {
        return competenceLevels;
    }

    public void setCompetenceLevels(List<CompetenceLevel> competenceLevels) {
        this.competenceLevels = competenceLevels;
    }

    @Override
    public String toString() {
        // [...]
    }

}

@Entity
@Table(name="competence_level")
public class CompetenceLevel {

    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    @Column(name="id_competence_level")
    private Long idCompetenceLevel;

    @OneToOne
    @JoinColumn(name="id_level")
    private Level level;

    @OneToOne
    @JoinColumn(name="id_profil")
    private Profil profil;

    private List<Experience> experiences;

    public CompetenceLevel() {
        super();
    }

    public Long getIdCompetenceLevel() {
        return idCompetenceLevel;
    }

    public void setIdCompetenceLevel(Long idCompetenceLevel) {
        this.idCompetenceLevel = idCompetenceLevel;
    }

    public Level getLevel() {
        return level;
    }

    public void setLevel(Level level) {
        this.level = level;
    }

    public Profil getProfil() {
        return profil;
    }

    public void setProfil(Profil profil) {
        this.profil = profil;
    }

    @ManyToMany(mappedBy = "competenceLevels")
    public List<Experience> getExperiences() {
        return experiences;
    }

    public void setExperiences(List<Experience> experiences) {
        this.experiences = experiences;
    }

    @Override
    public String toString() {
        // [...]
    }

}

我不明白为什么。我跟着这首芭蕾舞曲：

---

你有什么想法吗？谢谢。

原因很简单：不要在同一个持久类中混合字段和方法注释

---

Hibernate在这里生成一个不清楚的错误。如果您以前不面对错误，就很难找出错误的原因。

在代码中，您混合了字段访问和属性访问。看

我宁愿只使用其中一种可能性。我使用字段注释，就像您为

idProfil

所做的那样

在Nicholas S.Williams（非常非常好）的《Web应用程序的专业Java》一书中，我发现：

绝不能将JPA属性注释和JPA字段混用 同一实体中的注释。这样做会导致未指定的 行为，很可能导致错误。

为了清楚起见，我不会写这个

@ManyToOne
@JoinColumn（name=“id\u profile”）
私人财产；
//更好：
//私有Profil Profil；

好的，谢谢：）它可以工作。我在字段（）上写注释。现在，我有一个stakoverflow异常的问题。如果我删除CompetencyLevel中的经验列表，它会起作用：/但我需要它，你有什么想法吗？thx@Paladice谢谢你的快速接受。我想，如果你再问一个问题会更好。只需添加实体——问题标题中表格的描述很难阅读。