Automapping enums properties

[ianbondoc]

Is there a way for automapping a string to enums on select and enums to string when using as query parameter?

[davidmoten]

I'll have a look

[davidmoten]

What use case are you after, mapping a column directly to an enum or mapping a number of columns to a class where the fields are possibly enums? Both perhaps?

[ianbondoc]

Was hoping it can support mapping a number of columns to to a class where some fields are enums, not sure what you mean mapping a column directly to an enum, maybe that's also useful if you're after a single column where the value is represented by a an enum,

the other use case i have is the following where the enum is used as a parameter to a statement:

       val status = SomeEnumStatus.PENDING
        db.select("SELECT * FROM some_table t WHERE t.status = :status")
            .parameter("status", status)
            .autoMap(SomeEntity::class.java)

BTW, thanks a lot for an amazing lib, good solution to what big companies like ibm fail to address

[davidmoten]

Thanks, glad you find it useful.

I'd suggest you be quite specific with the parameter and pass .parameter("status", status.name()) or even better .parameter("status", status.value()) where value() is a custom method that carries the String name for use in db tables.

For automapping to an interface I suggest an approach like below. That way if you rename your enums (assuming that you serialize an enum to its name() method) then you won't destroy the coordination with the database:

interface PersonWithEnum {
        @Column
        String name();

        @Column("gender")
        String genderCharacter();
        
        default Gender gender() {
            return Gender.fromCode(genderCharacter());
        }
    }

I've added an example to DatabaseTest.java:

rxjava2-jdbc/rxjava2-jdbc/src/test/java/org/davidmoten/rx/jdbc/DatabaseTest.java

Lines 3553 to 3598 in a4355c0

	@Test
	public void testAutoMapToEnum() {
	try (Database db = Database.test()) {
	db.select(PersonWithEnum.class) //
	.get(x -> x.gender()) //
	.test() //
	.awaitDone(TIMEOUT_SECONDS, TimeUnit.SECONDS) //
	.assertValues(Gender.MALE, Gender.FEMALE, Gender.MALE) //
	.assertComplete();
	}
	}
	public enum Gender {
	MALE("M"), FEMALE("F"), OTHER("O");
	private final String code;
	private Gender(String code) {
	this.code = code;
	}
	public static Gender fromCode(String code) {
	if (code == null) {
	return null;
	}
	for (Gender g : Gender.values()) {
	if (code.equals(g.code)) {
	return g;
	}
	}
	return OTHER;
	}
	}
	@Query("select name, gender from person order by name")
	public interface PersonWithEnum {
	@Column
	String name();
	@Column("gender")
	String genderCharacter();
	default Gender gender() {
	return Gender.fromCode(genderCharacter());
	}
	}

[ianbondoc]

thanks that makes sense, i just got used to spring where it provides converters for you, but this is good enough