使用Spring Data JPA保存整数数组

Question

I am using spring data jpa with hibernate and postgres. I am trying to save an integer array in a column. I am using vlad mihaceas library for persisting the array into postgresql. The entity is as follows:-

@Type(type = "int-array")
@Column(name = "location", columnDefinition = "integer[]")  
private Integer[] locations;    

The corresponding location entity is

@Entity
@Table(name = "location_master")
public class Location implements Serializable {
    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private int id;
    @Column(name = "location_name")
    private String locationName;
}

The location ids are being saved in the db. But I am not able to display the in thymeleaf.

<tr>
    <td>Selected Locations</td>
    <td>[[${office.locations[0].locationName}]]</td>
</tr>

The following error has come up:-

org.springframework.expression.spel.SpelEvaluationException: EL1008E: Property or field 'locationName' cannot be found on object of type 'java.lang.Integer' - maybe not public or not valid?

Answer 1

org.springframework.expression.spel.SpelEvaluationException: EL1008E: Property or field 'locationName' cannot be found on object of type 'java.lang.Integer' - maybe not public or not valid?

The error has nothing to do with the use of the int-array of the hibernate-types project.

The error message is about the Spring Expression Language you used for setting the locationName which is a String property.

[[${office.locations[0].locationName}]]

The locations property is an Integer[] , but you treated it as a Location array.

What you want is a @OneToMany List<Location> instead:

@OneToMany(mappedBy="office", cascade = CascadeType.ALL, orphanRemoval = true)
private List<Location> locations = new ArrayList<>();  

And a @ManyToOne association in Location :

@ManyToOne(fetch = FetchType.LAZY)
private Office office;

Check out this article for more details about the best way to use a @OneToMany association.