Class PersistenceState


  • public class PersistenceState
    extends Object
    Defines a set of object states from the point of view of persistence. I.e. PersistenceState is the state of data stored in an object relative to the external persistence store. If an object's state matches the state of the persistence store, the object is COMMITTED. If object is not intended to be persistent or is not explicitly made persistent, the state is TRANSIENT, and so on.

    Object persistence states should not be modified directly. Rather it is a responsibility of a ObjectContext/DataContext to maintain correct state of the managed objects.

    • Field Summary

      Fields 
      Modifier and Type Field Description
      static int COMMITTED
      Describes a state of an object registered with DataContext/ObjectContext, whose fields exactly match the state of a corresponding database row.
      static int DELETED
      Describes a state of an object registered with DataContext/ObjectContext, that will be deleted from the database on the next commit.
      static int HOLLOW
      Describes a state of an object registered with DataContext/ObjectContext, and having a corresponding database row.
      static int MODIFIED
      Describes a state of an object registered with DataContext/ObjectContext, and having a corresponding database row.
      static int NEW
      Describes a state of an object freshly registered with DataContext/ObjectContext, but not committed to the database yet.
      static int TRANSIENT
      Describes a state of an object not registered with DataContext/ObjectContext, and therefore having no persistence features.
    • Field Detail

      • TRANSIENT

        public static final int TRANSIENT
        Describes a state of an object not registered with DataContext/ObjectContext, and therefore having no persistence features.
        See Also:
        Constant Field Values
      • NEW

        public static final int NEW
        Describes a state of an object freshly registered with DataContext/ObjectContext, but not committed to the database yet. So there is no corresponding database record for this object just yet.
        See Also:
        Constant Field Values
      • COMMITTED

        public static final int COMMITTED
        Describes a state of an object registered with DataContext/ObjectContext, whose fields exactly match the state of a corresponding database row. This state is not fully "clean", since database record may have been externally modified.
        See Also:
        Constant Field Values
      • MODIFIED

        public static final int MODIFIED
        Describes a state of an object registered with DataContext/ObjectContext, and having a corresponding database row. This object state is known to be locally modified and different from the database state.
        See Also:
        Constant Field Values
      • HOLLOW

        public static final int HOLLOW
        Describes a state of an object registered with DataContext/ObjectContext, and having a corresponding database row. This object does not store any fields except for its id (it is "hollow"), so next time it is accessed, it will be populated from the database by the context. In this respect this is a real "clean" object.
        See Also:
        Constant Field Values
      • DELETED

        public static final int DELETED
        Describes a state of an object registered with DataContext/ObjectContext, that will be deleted from the database on the next commit.
        See Also:
        Constant Field Values
    • Constructor Detail

      • PersistenceState

        public PersistenceState()
    • Method Detail

      • persistenceStateName

        public static String persistenceStateName​(int persistenceState)
        Returns String label for persistence state. Used for debugging.