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org.hibernate.MappingException: Could not determine type for: java.util.List, at table: College, for columns: [org.hibernate.mapping.Column(students)]

You are using field access strategy (determined by @Id annotation). Put any JPA related annotation right above each field instead of getter property

@OneToMany(targetEntity=Student.class, mappedBy="college", fetch=FetchType.EAGER)
private List<Student> students;

Adding the @ElementCollection to the List field solved this issue:

    @Column
    @ElementCollection(targetClass=Integer.class)
    private List<Integer> countries;

Problem with Access strategies

As a JPA provider, Hibernate can introspect both the entity attributes (instance fields) or the accessors (instance properties). By default, the placement of the @Id annotation gives the default access strategy. When placed on a field, Hibernate will assume field-based access. Placed on the identifier getter, Hibernate will use property-based access.

Field-based access

When using field-based access, adding other entity-level methods is much more flexible because Hibernate won’t consider those part of the persistence state

@Entity
public class Simple {

@Id
private Integer id;

@OneToMany(targetEntity=Student.class, mappedBy="college", 
fetch=FetchType.EAGER)
private List<Student> students;

//getter +setter
}

Property-based access

When using property-based access, Hibernate uses the accessors for both reading and writing the entity state

@Entity
public class Simple {

private Integer id;
private List<Student> students;

@Id
public Integer getId() {
    return id;
}

public void setId( Integer id ) {
    this.id = id;
}
@OneToMany(targetEntity=Student.class, mappedBy="college", 
fetch=FetchType.EAGER)
public List<Student> getStudents() {
   return students;
}
public void setStudents(List<Student> students) {
    this.students = students;
}

}

But you can't use both Field-based and Property-based access at the same time. It will show like that error for you

For more idea follow this


@Access(AccessType.PROPERTY)
@OneToOne(cascade = CascadeType.ALL, fetch = FetchType.EAGER)
@JoinColumn(name="userId")
public User getUser() {
    return user;
}

I have the same problems, I solved it by add @Access(AccessType.PROPERTY)


Just insert the @ElementCollection annotation over your array list variable, as below:

@ElementCollection
private List<Price> prices = new ArrayList<Price>();

I hope this helps


In my case it was stupid missing of @OneToOne annotation, i set @MapsId without it


Though I am new to hibernate but with little research (trial and error we can say) I found out that it is due to inconsistency in annotating the methods/fileds.

when you are annotating @ID on variable make sure all other annotations are also done on variable only and when you are annotating it on getter method same make sure you are annotating all other getter methods only and not their respective variables.