Annotation Type Entity

@Retention(CLASS) @Target(TYPE) public @interface Entity

Marks a POJO or PropertyBusinessObject as a persistent entity, in the app and on the Codename One backend alike.

At build time the Codename One Maven plugin generates a reflection-free Dao next to the class with createTable, insert, update, delete, findById, findAll, and find(where, params) methods. Application code reaches the generated dao through com.codename1.orm.EntityManager:

@Entity(table="users")
public class User {
    @Id(autoIncrement=true) public long id;
    @Column(name="full_name") public String name;
    public int age;
}

EntityManager em = EntityManager.open("MyDB");
Dao<User> users = em.dao(User.class);
users.createTable();
users.insert(new User());

The dao uses the same prepared-statement protocol as the existing com.codename1.db.Database; no Class.forName lookups, so the binding survives ParparVM rename / R8 obfuscation in shipped builds.

An entity is the one kind of class both halves of an application own: the app stores rows of it in its local SQLite file and the server stores rows of it in PostgreSQL, MySQL or SQLite. The backend runtime compiles this very annotation (it is marked SharedWithBackend), so the entity class can be a single file in a module both sides depend on. What differs is what the build GENERATES from it: against the core the processor emits a dao over com.codename1.db.Database, against the backend one over com.codename1.backend.Database, whose SQL is built for whichever engine the connection turns out to be. The class needs a public no-arg constructor.

Every field that is not static or transient is persistent, whatever its access; @DbTransient leaves one out. A non-public field is read and written through a static accessor the build weaves into the class that declares it, so the generated dao needs no reflection on any platform.

  • Optional Element Summary

    Optional Elements
    Modifier and Type
    Optional Element
    Description
    Index[]
    indexes
    Additional indexes created with the entity table.
    String
    table
    SQL table name.

  • Element Details

    • table

      String table
      SQL table name. When blank the app names the table after the simple class name, and the backend after the same name in snake case (RideEvent becomes ride_event), as Spring Boot does.
      Default:
      ""

    • indexes

      Index[] indexes
      Additional indexes created with the entity table.
      Returns:
      index declarations, empty by default
      Default:
      {}