Class BaseDataObject
- All Implemented Interfaces:
Serializable
,DataObject
,Persistent
,Validating
- Direct Known Subclasses:
CayenneDataObject
,HybridDataObject
DataObject
,
have no assumption about how data is actually stored.
Three variants are currently supported:
- field based storage, e.g. each entity class will directly define fields to store data
-
Map
based storage, e.g. values will be stored in general Map (CayenneDataObject
) - mixed fields and generic Map to store runtime attributes (
HybridDataObject
)
This class can be used directly as superclass for field-based data objects.
To create own implementation of DataObject
with custom field storage logic it is enough
to implement readPropertyDirectly(String)
and writePropertyDirectly(String, Object)
methods
and serialization support if needed (helper methods writeState(ObjectOutputStream)
and readState(ObjectInputStream)
are provided).
- Since:
- 4.1
- See Also:
-
Field Summary
Fields inherited from class org.apache.cayenne.PersistentObject
objectContext, objectId, persistenceState
Fields inherited from interface org.apache.cayenne.DataObject
DEFAULT_VERSION
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Constructor Summary
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Method Summary
Modifier and TypeMethodDescriptionvoid
addToManyTarget
(String relName, DataObject value, boolean setReverse) Adds an object to a to-many relationship.protected void
appendProperties
(StringBuffer buffer) protected void
beforePropertyRead
(String propName) protected void
beforePropertyWrite
(String propName, Object oldValue, Object newValue) long
Returns a version of a DataRow snapshot that was used to create this object.readNestedProperty
(String path) Returns a value of the property identified by a property path.readProperty
(String propertyName) Returns a value of the property identified by propName.readPropertyDirectly
(String propName) Returns mapped property value as curently stored in the DataObject.protected void
protected void
void
removeToManyTarget
(String relName, DataObject value, boolean setReverse) Removes an object from a to-many relationship.void
setObjectContext
(ObjectContext objectContext) void
setPersistenceState
(int persistenceState) protected void
setReverseRelationship
(String relName, DataObject val) Initializes reverse relationship from objectval
to this object.void
setSnapshotVersion
(long snapshotVersion) List
<? extends DataObject> setToManyTarget
(String relName, Collection<? extends DataObject> values, boolean setReverse) Sets the relationships to the specifiedDataObject
objects.void
setToOneTarget
(String relationshipName, DataObject value, boolean setReverse) Sets to-one relationship to a new value.toString()
toStringBuffer
(StringBuffer buffer, boolean fullDesc) A variation of "toString" method, that may be more efficient in some cases.protected void
unsetReverseRelationship
(String relName, DataObject val) Removes current object from reverse relationship of objectval
to this object.void
validateForDelete
(ValidationResult validationResult) This implementation does nothing.void
validateForInsert
(ValidationResult validationResult) protected void
validateForSave
(ValidationResult validationResult) Performs property validation of the object, appending any validation failures to the provided validationResult object.void
validateForUpdate
(ValidationResult validationResult) protected void
willConnect
(String relationshipName, Persistent object) Called before establishing a relationship with another object.void
writeProperty
(String propName, Object val) Sets the property to the new value.void
writePropertyDirectly
(String propName, Object val) Modifies a value of a named property without altering the object state in any way, and without triggering any database operations.protected void
protected void
Methods inherited from class org.apache.cayenne.PersistentObject
getMapKey, getObjectContext, getObjectId, getPersistenceState, setObjectId
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
Methods inherited from interface org.apache.cayenne.Persistent
getObjectContext, getObjectId, getPersistenceState, setObjectId
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Field Details
-
snapshotVersion
protected long snapshotVersion
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-
Constructor Details
-
BaseDataObject
public BaseDataObject()
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Method Details
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readPropertyDirectly
Description copied from interface:DataObject
Returns mapped property value as curently stored in the DataObject. Returned value maybe a fault or a real value. This method will not attempt to resolve faults, or to read unmapped properties.- Specified by:
readPropertyDirectly
in interfaceDataObject
-
writePropertyDirectly
Description copied from interface:DataObject
Modifies a value of a named property without altering the object state in any way, and without triggering any database operations. This method is intended mostly for internal use by Cayenne framework, and shouldn't be called from the application code.- Specified by:
writePropertyDirectly
in interfaceDataObject
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beforePropertyRead
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beforePropertyWrite
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readProperty
Description copied from interface:DataObject
Returns a value of the property identified by propName. Resolves faults if needed. This method can safely be used instead of or in addition to the auto-generated property accessors in subclasses of CayenneDataObject.- Specified by:
readProperty
in interfaceDataObject
-
readNestedProperty
Returns a value of the property identified by a property path. Supports reading both mapped and unmapped properties. Unmapped properties are accessed in a manner consistent with JavaBeans specification.Property path (or nested property) is a dot-separated path used to traverse object relationships until the final object is found. If a null object found while traversing path, null is returned. If a list is encountered in the middle of the path, CayenneRuntimeException is thrown. Unlike
readPropertyDirectly(String)
, this method will resolve an object if it is HOLLOW.Examples:
- Read this object property:
String name = (String)artist.readNestedProperty("name");
- Read an object related to this object:
Gallery g = (Gallery)paintingInfo.readNestedProperty("toPainting.toGallery");
- Read a property of an object related to this object:
String name = (String)painting.readNestedProperty("toArtist.artistName");
- Read to-many relationship list:
List exhibits = (List)painting.readNestedProperty("toGallery.exhibitArray");
- Read to-many relationship in the middle of the path:
List<String> names = (List<String>)artist.readNestedProperty("paintingArray.paintingName");
- Specified by:
readNestedProperty
in interfaceDataObject
- Since:
- 1.0.5
- Read this object property:
-
writeProperty
Description copied from interface:DataObject
Sets the property to the new value. Resolves faults if needed. This method can be safely used instead of or in addition to the auto-generated property modifiers to set simple properties. Note that to set to-one relationships useDataObject.setToOneTarget(String, DataObject, boolean)
.- Specified by:
writeProperty
in interfaceDataObject
- Parameters:
propName
- a name of the bean property being modified.val
- a new value of the property.
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removeToManyTarget
Description copied from interface:DataObject
Removes an object from a to-many relationship.- Specified by:
removeToManyTarget
in interfaceDataObject
-
addToManyTarget
Description copied from interface:DataObject
Adds an object to a to-many relationship.- Specified by:
addToManyTarget
in interfaceDataObject
-
setToManyTarget
public List<? extends DataObject> setToManyTarget(String relName, Collection<? extends DataObject> values, boolean setReverse) Sets the relationships to the specifiedDataObject
objects.New relationships will be created with
addToManyTarget(String, org.apache.cayenne.DataObject, boolean)
, already established relationships stay untouched. Missing relationships will be removed withremoveToManyTarget(String, org.apache.cayenne.DataObject, boolean)
and returnd as List. You may delete them manually.Notice: Moving an object relationship to another object, is still needing an manually "unregister" from the first object by
removeToManyTarget(String, org.apache.cayenne.DataObject, boolean)
- Parameters:
relName
- name of the relationvalues
-DataObject
objects of thisCollection
are set to the object. No changes will be made to the theCollection
, a copy is used. It is safe to pass a persistedCollection
of another object.setReverse
- update reverse relationships- Returns:
List<? extends DataObject>
of unrelated DataObjects. If no relationship was removed an empty List is returned.- Throws:
IllegalArgumentException
- if no relationship could be read by relName, or if the passedCollection
is null. To clear all relationships use an emptyCollection
UnsupportedOperationException
- if the relation Collection Type is neitherjava.util.Collection
norjava.util.Map
- Since:
- 4.0
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setToOneTarget
Description copied from interface:DataObject
Sets to-one relationship to a new value. Resolves faults if needed. This method can safely be used instead of or in addition to the auto-generated property modifiers to set properties that are to-one relationships.- Specified by:
setToOneTarget
in interfaceDataObject
- Parameters:
relationshipName
- a name of the bean property being modified - same as the name of ObjRelationship.value
- a new value of the property.setReverse
- whether to update the reverse relationship pointing from the old and new values of the property to this object.
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willConnect
Called before establishing a relationship with another object. Applies "persistence by reachability" logic, pulling one of the two objects to a DataConext of another object in case one of the objects is transient. If both objects are persistent, and they don't have the same DataContext, CayenneRuntimeException is thrown.- Since:
- 1.2
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setReverseRelationship
Initializes reverse relationship from objectval
to this object.- Parameters:
relName
- name of relationship from this object toval
.
-
unsetReverseRelationship
Removes current object from reverse relationship of objectval
to this object. -
setPersistenceState
public void setPersistenceState(int persistenceState) - Specified by:
setPersistenceState
in interfacePersistent
- Overrides:
setPersistenceState
in classPersistentObject
-
getSnapshotVersion
public long getSnapshotVersion()Description copied from interface:DataObject
Returns a version of a DataRow snapshot that was used to create this object.- Specified by:
getSnapshotVersion
in interfaceDataObject
- Since:
- 1.1
-
setSnapshotVersion
public void setSnapshotVersion(long snapshotVersion) - Specified by:
setSnapshotVersion
in interfaceDataObject
- Since:
- 1.1
-
validateForSave
Performs property validation of the object, appending any validation failures to the provided validationResult object. This method is invoked from "validateFor.." before committing a NEW or MODIFIED object to the database. Validation includes checking for null values and value sizes. CayenneDataObject subclasses may override this method, calling super.- Since:
- 1.1
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validateForInsert
CallsvalidateForSave(ValidationResult)
. CayenneDataObject subclasses may override it providing validation logic that should be executed for the newly created objects before saving them.- Specified by:
validateForInsert
in interfaceValidating
- Since:
- 1.1
-
validateForUpdate
CallsvalidateForSave(ValidationResult)
. CayenneDataObject subclasses may override it providing validation logic that should be executed for the modified objects before saving them.- Specified by:
validateForUpdate
in interfaceValidating
- Since:
- 1.1
-
validateForDelete
This implementation does nothing. CayenneDataObject subclasses may override it providing validation logic that should be executed for the deleted objects before committing them.- Specified by:
validateForDelete
in interfaceValidating
- Since:
- 1.1
-
setObjectContext
- Specified by:
setObjectContext
in interfacePersistent
- Overrides:
setObjectContext
in classPersistentObject
- Since:
- 1.2
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writeSerialized
- Throws:
IOException
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readSerialized
- Throws:
IOException
ClassNotFoundException
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writeState
- Throws:
IOException
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readState
- Throws:
IOException
ClassNotFoundException
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toStringBuffer
A variation of "toString" method, that may be more efficient in some cases. For example when printing a list of objects into the same String. -
appendProperties
-
toString
- Overrides:
toString
in classPersistentObject
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