Package org.apache.cayenne.util

Class PersistentObjectHolder<E>

java.lang.Object

org.apache.cayenne.util.RelationshipFault<E>

org.apache.cayenne.util.PersistentObjectHolder<E>

All Implemented Interfaces:

Serializable, ValueHolder<E>

public class PersistentObjectHolder<E>
extends RelationshipFault<E>
implements ValueHolder<E>

A ValueHolder implementation that holds a single Persistent object related to an object used to initialize PersistentObjectHolder. Value is resolved on first access.

Since:

1.2

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
protected boolean	fault
protected E	value

Fields inherited from class org.apache.cayenne.util.RelationshipFault

relationshipName, relationshipOwner

Constructor Summary

Constructors

Constructor	Description
PersistentObjectHolder(Persistent relationshipOwner, String relationshipName)

Method Summary

Modifier and Type	Method	Description
protected void	connect(Persistent persistent)	Returns an object that should be stored as a value in this ValueHolder, ensuring that it is registered with the same context.
E	getValue()	Returns a value resolving it via a query on the first call to this method.
E	getValueDirectly()	Retrieves ValueHolder value without triggering fault resolution.
void	invalidate()	Turns a ValueHolder into a fault.
boolean	isFault()	Returns true if this holder is not resolved, meaning its object is not yet known.
protected void	mergeLocalChanges(List resolved)
protected void	resolve()	Reads an object from the database.
E	setValue(E value)	Sets an object value, marking this ValueHolder as resolved.
E	setValueDirectly(E value)	Sets ValueHolder vaue without triggering fault resolution.

Methods inherited from class org.apache.cayenne.util.RelationshipFault

getRelationshipName, getRelationshipOwner, isTransientParent, isUncommittedParent, resolveFromDB, updateReverse

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

fault

protected boolean fault

value

protected E value

Constructor Detail

PersistentObjectHolder

public PersistentObjectHolder(Persistent relationshipOwner,
                              String relationshipName)

Method Detail

isFault

public boolean isFault()

Returns true if this holder is not resolved, meaning its object is not yet known.

Specified by:

isFault in interface ValueHolder<E>

invalidate

public void invalidate()

Description copied from interface: ValueHolder

Turns a ValueHolder into a fault.

Specified by:

invalidate in interface ValueHolder<E>

getValue

public E getValue()
           throws CayenneRuntimeException

Returns a value resolving it via a query on the first call to this method.

Specified by:

getValue in interface ValueHolder<E>

Throws:

CayenneRuntimeException

getValueDirectly

public E getValueDirectly()
                   throws CayenneRuntimeException

Description copied from interface: ValueHolder

Retrieves ValueHolder value without triggering fault resolution.

Specified by:

getValueDirectly in interface ValueHolder<E>

Throws:

CayenneRuntimeException

setValue

public E setValue(E value)
           throws CayenneRuntimeException

Sets an object value, marking this ValueHolder as resolved.

Specified by:

setValue in interface ValueHolder<E>

Parameters:

value - a new value of the ValueHolder.

Returns:

a previous value saved in the ValueHolder.

Throws:

CayenneRuntimeException

setValueDirectly

public E setValueDirectly(E value)
                   throws CayenneRuntimeException

Description copied from interface: ValueHolder

Sets ValueHolder vaue without triggering fault resolution.

Specified by:

setValueDirectly in interface ValueHolder<E>

Throws:

CayenneRuntimeException

connect

protected void connect(Persistent persistent)

Returns an object that should be stored as a value in this ValueHolder, ensuring that it is registered with the same context.

resolve

protected void resolve()

Reads an object from the database.

mergeLocalChanges

protected void mergeLocalChanges(List resolved)

Specified by:

mergeLocalChanges in class RelationshipFault<E>