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Field Names Without String Literals

Avoid hard‑coded string field names in queries to prevent typos and ease refactors/migrations.

Option 1: Enums (recommended for teams) 

@Entity
public class User {
  @Id private MorphiumId id;
  private String userName;
  public enum Fields { id, userName }
}

var q = morphium.createQueryFor(User.class)
  .f(User.Fields.userName).eq("alice");

Option 2: Lambda property extractor (no codegen)

  • Use a method reference to a getter; Morphium will receive the Java field name
  • A small helper is included: de.caluga.morphium.query.FieldNames and Property 
    import static de.caluga.morphium.query.FieldNames.of;

var q = morphium.createQueryFor(User.class)
  .f(of(User::getUserName)).eq("alice");

Notes

  • Works with @Entity(translateCamelCase = true)—use Java field names in queries, Morphium maps to stored names.
  • Requires normal JavaBean getter names (getXxx or isXxx).

Option 3: Code generation at build time (annotation processor)

  • Create a simple JSR‑269 annotation processor that scans @Entity classes and generates Fields enums or User_ constants classes using JavaPoet.
  • Wire it via Maven’s maven-compiler-plugin annotationProcessorPaths or run a generator via exec-maven-plugin in the generate-sources phase to write sources into target/generated-sources.
  • Pros: strongly typed enums/constants; Cons: extra module/maintenance.

Recommendation

  • Start with Enums or the Lambda extractor. If your model is large or changes often, consider adding a lightweight codegen step later.