org.apache.cayenne

Class PersistenceState

java.lang.Object

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

Fields

Modifier and Type	Field and 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.

Constructor Summary

Constructors

Constructor and Description
PersistenceState()

Method Summary

Modifier and Type	Method and Description
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.

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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.

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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.