带有枚举的JPA 2 Criteria API

Question

I have the following entity :

public class Role extends AbstractDomain<Long> {
    @Id
    @Column
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "idgen_x")
    @UiInfo(name = "Identifiant")
    private Long roleId;

    @Column
    @UiInfo(name = "Libellé")
    private String lib;

    @Column
    @UiInfo(name = "Provenance")
    private EnumP enumPID;
}

EnumP :

public enum EnumP {
    W, X, Y, Z;
}

And using JPA Criteria API I want to get a list of Role where Role.enumPID in an array contains the enum values as strings.

This is the code of the Predicate I tried :

builder.isTrue(fromRole.get(Role_.enumPID).in((Object[]) filter.getFilterSetValues()))

And the filter.getFilterSetValues() contains the enum values as strings, as following :

["X","Y"]

But I get this error message :

java.lang.IllegalArgumentException: Parameter value [X] did not match expected type [***.EnumP (n/a)]

How can I solve this ?

Answer 1

You should adequately annotate the enum field first:

@Enumerated(EnumType.STRING)
@UiInfo(name = "Provenance")
private EnumP enumPID;

Then you should be using the particular EnumP elements in your queries as params, not their String equivalents.

You would need to transform the collection of Strings into corresponding collection of EnumP objects:

public static List<EnumP> fromStringArray(String[] array){
    List<EnumP> returnList = new ArrayList<>; 

    for(String element: array){
       for(EnumP enumP: EnumP.values()){
          if(enumP.name().equals(element)){
             returnList.add(enumP);
          }
       }
    }    

    return returnList;
}