Class EntityManager

java.lang.Object
com.codename1.orm.EntityManager
public final class EntityManager extends Object

Public entry point for the build-time SQLite ORM.

@Entity classes get a generated dao at build time. Each dao's static initializer self-registers with this registry. The registry stays empty until something triggers each generated class's <clinit>:

  • iOS / Android -- the build server probes the project zip for cn1app.DaoBootstrap and splices a new cn1app.DaoBootstrap(); into the per-build application stub before Display.init.
  • JavaSE simulator + desktop -- JavaSEPort#postInit calls Class.forName("cn1app.DaoBootstrap") so the registry is populated on the same boundary.
  • Unit tests / manual init -- application code can call EntityManager.registerDao(...) directly.
EntityManager em = EntityManager.open("MyApp.db");
Dao<User> users = em.dao(User.class);
users.createTable();
users.insert(new User("alice"));
for (User u : users.findAll()) { ... }
em.close();

The registry is keyed on getClass().getName() so it survives ParparVM rename and R8 obfuscation: both the registration site and the lookup site see the same renamed name within a single execution.

  • Method Details

    • open

      public static EntityManager open(String databaseName) throws IOException
      Opens (or creates) the SQLite file databaseName via Display.openOrCreate. Throws IOException when the platform refuses to provide a SQLite database.
      Throws:
      IOException

    • open

      public static EntityManager open(Database db)
      Wraps an existing Database (e.g. one opened with a custom path) in an EntityManager. The caller retains ownership; close() closes the database.

    • registerDao

      public static <T> void registerDao(Dao<T> dao)
      Installs dao under dao.type().getName(). The generated per-class dao's static initializer calls this; hand-written daos for classes outside the build's annotation scan call it explicitly.

    • dao

      public <T> Dao<T> dao(Class<T> entityClass)
      Returns the dao for entityClass, freshly attached to this entity manager's Database. Throws IllegalStateException when no dao was generated for the class -- typically because @Entity is missing or the process-annotations Mojo did not run.

    • openSession

      public Session openSession()
      Opens an independent managed persistence context over this manager's database. The caller must close the session. Use one thread per session and complete every transaction on that thread. Closing a session never commits it.
      Returns:
      a new persistence context with independent managed entity state
      Throws:
      IllegalStateException - if this manager is closed

    • database

      public Database database()
      The underlying Database. Use it for raw SQL when the dao surface isn't enough.

    • beginTransaction

      public void beginTransaction() throws IOException
      Begin a transaction. Equivalent to database().beginTransaction().
      Throws:
      IOException

    • commitTransaction

      public void commitTransaction() throws IOException
      Commit the current transaction.
      Throws:
      IOException

    • rollbackTransaction

      public void rollbackTransaction() throws IOException
      Roll back the current transaction.
      Throws:
      IOException

    • close

      public void close() throws IOException
      Close the underlying database. Idempotent.
      Throws:
      IOException