org.apache.cayenne
Class PersistenceState

java.lang.Object
  extended by org.apache.cayenne.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
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.
 
Constructor Summary
PersistenceState()
           
 
Method Summary
static String persistenceStateName(int persistenceState)
          Returns String label for persistence state.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

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.



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