Hibernate ORM - hibernate-core 6.4.4.Final · org.hibernate.event.spi.MergeContext

MergeContext is a specialized Map implementation used by a merge event listener to keep track of each entity being merged and its corresponding managed result. An entity to be merged may to be added to the MergeContext before the merge operation cascades to the entity.

A merge entity (the mergeEntity method parameter) is an entity being merged via EventSource#merge(Object mergeEntity).
A managed entity (the managedEntity method parameter) is the managed entity that is the result of merging an entity.

A merge entity can be transient, detached, or managed. If it is managed, then it is identical to its resulting managed entity.

If put(Object mergeEntity, Object managedEntity) is called, and this MergeContext already contains an entry with a different entity as the key, but with the same (managed entity) value, this means that multiple entity representations for the same persistent entity are being merged. In this situation, EntityCopyObserver#entityCopyDetected( Object managedEntity, Object mergeEntity1, Object mergeEntity2, EventSource) is called to determine an appropriate resolution.

There are several restrictions.

Methods that return collections (e.g., keySet(), values(), entrySet()) return an unmodifiable view of the collection.
If managedEntity or put(Object mergeEntity, Object managedEntity, boolean isOperatedOn) is executed and this MergeContext already contains a cross reference for mergeEntity, then managedEntity must be identical to the entity already associated with mergeEntity.
If putAll(Map map) is executed, the previous restriction applies to each entry in the Map.
The remove(Object) operation is not supported; the only way to remove data from a MergeContext is by calling clear().
The map returned by invertMap() will only contain the "newest" (most recently added) managed-to-merge cross-reference to its merge entity.

The following method is intended to be used by an implementation of org.hibernate.event.spi.MergeEventListener to add a merge entity and its corresponding managed entity to a MergeContext and indicate if the merge operation is being performed on the merge entity yet.

MergeContext#put(Object mergeEntity, Object managedEntity, boolean isOperatedOn)

The following method is intended to be used by a MergeEventListener to indicate whether the merge operation is being performed on a merge entity already in the MergeContext:

MergeContext#setOperatedOn(Object mergeEntity, boolean isOperatedOn)

Field Summary

Modifier and Type	Field and Description
private final EntityCopyObserver	entityCopyObserver
private final Map<Object, Object>	managedToMergeEntityXref
private final Map<Object, Boolean>	mergeEntityToOperatedOnFlagMap
private final Map<Object, Object>	mergeToManagedEntityXref
private final EventSource	session

Constructor Summary

Access	Constructor and Description
public	MergeContext(EventSource session, EntityCopyObserver entityCopyObserver)

Method Summary

Modifier and Type	Method and Description
public void	clear() Implements java.util.Map.clear. Clears the MergeContext.
public boolean	Returns: true if this MergeContext contains a cross-reference for the specified merge entity containsKey(Object must be non-null mergeEntity) Implements java.util.Map.containsKey. Returns true if this MergeContext contains a cross-reference for the specified merge entity to a managed entity result.
public boolean	Returns: true if this MergeContext contains a cross-reference from the specified managed entity to a merge entity containsValue(Object must be non-null managedEntity) Implements java.util.Map.containsValue. Returns true if this MergeContext contains a cross-reference from the specified managed entity to a merge entity.
public Set<Map.Entry<Object, Object>>	Returns: an unmodifiable set view of the merge-to-managed entity cross-references contained in this MergeContext entrySet() Implements java.util.Map.entrySet. Returns an unmodifiable set view of the merge-to-managed entity cross-references contained in this MergeContext.
public Object	Returns: the managed entity associated with the specified merge Entity get(Object the merge entity; must be non-null mergeEntity) Implements java.util.Map.get. Returns the managed entity associated with the specified merge Entity.
public Map<Object, Object>	Returns: an unmodifiable map view of the managed-to-merge entity cross-references. invertMap() Returns an unmodifiable map view of the managed-to-merge entity cross-references.
public boolean	Returns: true if this MergeContext contains no merge-to-managed entity cross-references. isEmpty() Implements java.util.Map.isEmpty. Returns true if this MergeContext contains no merge-to-managed entity cross-references.
public boolean	Returns: true if the listener is performing the merge operation on the specified merge entity; false, if there is no mapping for mergeEntity. isOperatedOn(Object the merge entity; must be non-null mergeEntity) Returns true if the listener is performing the merge operation on the specified merge entity.
public Set<Object>	Returns: an unmodifiable set view of the merge entities contained in this MergeContext keySet() Implements java.util.Map.keySet. Returns an unmodifiable set view of the merge entities contained in this MergeContext
private String	printEntity(Object entity)
public Object	Returns: previous managed entity associated with specified merge entity, or null if there was no mapping for mergeEntity. put(Object the merge entity; must be non-null mergeEntity, Object the managed entity result; must be non-null managedEntity) Implements java.util.Map.put. Associates the specified merge entity with the specified managed entity result in this MergeContext.
public Object	Returns: previous managed entity associated with specified merge entity, or null if there was no mapping for mergeEntity. put(Object the merge entity; must be non-null mergeEntity, Object the managed entity; must be non-null managedEntity, boolean indicates if the merge operation is performed on the mergeEntity. isOperatedOn) Associates the specified merge entity with the specified managed entity in this MergeContext.
public void	putAll(Map<?, ?> keys and values must be non-null map) Implements java.util.Map.putAll. Copies all of the mappings from the specified Map to this MergeContext.
public Object	remove(Object the merge entity. mergeEntity) Implements java.util.Map.remove. The remove operation is not supported.
public void	setOperatedOn(Object must be non-null and this MergeContext must contain a cross-reference for mergeEntity to a managed entity mergeEntity, boolean isOperatedOn) Set flag to indicate if the listener is performing the merge operation on the specified merge entity.
public int	Returns: the number of merge-to-managed entity cross-references in this MergeContext size() Implements java.util.Map.size. Returns the number of merge-to-managed entity cross-references in this MergeContext
public Collection<Object>	Returns: an unmodifiable Set view of managed entities contained in this MergeContext values() Implements java.util.Map.values. Returns an unmodifiable Set view of managed entities contained in this MergeContext.

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll toString wait wait wait

Field Detail

entityCopyObserver	back to summary
private final EntityCopyObserver entityCopyObserver

managedToMergeEntityXref	back to summary
private final Map<Object, Object> managedToMergeEntityXref

mergeEntityToOperatedOnFlagMap	back to summary
private final Map<Object, Boolean> mergeEntityToOperatedOnFlagMap

mergeToManagedEntityXref	back to summary
private final Map<Object, Object> mergeToManagedEntityXref

session	back to summary
private final EventSource session

Constructor Detail

MergeContext	back to summary
public MergeContext(EventSource session, EntityCopyObserver entityCopyObserver)

Method Detail

clear	back to summary
public void clear() Implements java.util.Map.clear. Clears the MergeContext.

clear

back to summary

public void clear()

Implements java.util.Map.clear.

Clears the MergeContext.

containsKey	back to summary
public boolean containsKey(Object mergeEntity) Implements java.util.Map.containsKey. Returns true if this MergeContext contains a cross-reference for the specified merge entity to a managed entity result. Parameters mergeEntity:Object must be non-null Returns:boolean true if this MergeContext contains a cross-reference for the specified merge entity Exceptions NullPointerException: if mergeEntity is null

containsKey

back to summary

public boolean containsKey(Object mergeEntity)

Implements java.util.Map.containsKey.

Returns true if this MergeContext contains a cross-reference for the specified merge entity to a managed entity result.

Parameters

mergeEntity:Object: must be non-null

Returns:boolean

true if this MergeContext contains a cross-reference for the specified merge entity

Exceptions

NullPointerException:: if mergeEntity is null

containsValue	back to summary
public boolean containsValue(Object managedEntity) Implements java.util.Map.containsValue. Returns true if this MergeContext contains a cross-reference from the specified managed entity to a merge entity. Parameters managedEntity:Object must be non-null Returns:boolean true if this MergeContext contains a cross-reference from the specified managed entity to a merge entity Exceptions NullPointerException: if managedEntity is null

containsValue

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public boolean containsValue(Object managedEntity)

Implements java.util.Map.containsValue.

Returns true if this MergeContext contains a cross-reference from the specified managed entity to a merge entity.

Parameters

managedEntity:Object: must be non-null

Returns:boolean

true if this MergeContext contains a cross-reference from the specified managed entity to a merge entity

Exceptions

NullPointerException:: if managedEntity is null

entrySet back to summary

entrySet	back to summary
public Set<Map.Entry<Object, Object>> entrySet() Implements java.util.Map.entrySet. Returns an unmodifiable set view of the merge-to-managed entity cross-references contained in this MergeContext. Returns:Set<Map.Entry<Object, Object>> an unmodifiable set view of the merge-to-managed entity cross-references contained in this MergeContext See Also `Collections#unmodifiableSet(Set)`

public Set<Map.Entry<Object, Object>> entrySet()

Implements java.util.Map.entrySet.

Returns an unmodifiable set view of the merge-to-managed entity cross-references contained in this MergeContext.

Returns:Set<Map.Entry<Object, Object>>: an unmodifiable set view of the merge-to-managed entity cross-references contained in this MergeContext
See Also: Collections#unmodifiableSet(Set)

get	back to summary
public Object get(Object mergeEntity) Implements java.util.Map.get. Returns the managed entity associated with the specified merge Entity. Parameters mergeEntity:Object the merge entity; must be non-null Returns:Object the managed entity associated with the specified merge Entity Exceptions NullPointerException: if mergeEntity is null

get

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public Object get(Object mergeEntity)

Implements java.util.Map.get.

Returns the managed entity associated with the specified merge Entity.

Parameters

mergeEntity:Object: the merge entity; must be non-null

Returns:Object

the managed entity associated with the specified merge Entity

Exceptions

NullPointerException:: if mergeEntity is null

invertMap back to summary

invertMap	back to summary
public Map<Object, Object> invertMap() Returns an unmodifiable map view of the managed-to-merge entity cross-references. The returned Map will contain a cross-reference from each managed entity to the most recently associated merge entity that was most recently put in the MergeContext. Returns:Map<Object, Object> an unmodifiable map view of the managed-to-merge entity cross-references. See Also `Collections#unmodifiableMap(Map)`

public Map<Object, Object> invertMap()

Returns an unmodifiable map view of the managed-to-merge entity cross-references. The returned Map will contain a cross-reference from each managed entity to the most recently associated merge entity that was most recently put in the MergeContext.

Returns:Map<Object, Object>: an unmodifiable map view of the managed-to-merge entity cross-references.
See Also: Collections#unmodifiableMap(Map)

isEmpty	back to summary
public boolean isEmpty() Implements java.util.Map.isEmpty. Returns true if this MergeContext contains no merge-to-managed entity cross-references. Returns:boolean true if this MergeContext contains no merge-to-managed entity cross-references.

isEmpty

back to summary

public boolean isEmpty()

Implements java.util.Map.isEmpty.

Returns true if this MergeContext contains no merge-to-managed entity cross-references.

Returns:boolean: true if this MergeContext contains no merge-to-managed entity cross-references.

isOperatedOn	back to summary
public boolean isOperatedOn(Object mergeEntity) Returns true if the listener is performing the merge operation on the specified merge entity. Parameters mergeEntity:Object the merge entity; must be non-null Returns:boolean true if the listener is performing the merge operation on the specified merge entity; false, if there is no mapping for mergeEntity. Exceptions NullPointerException: if mergeEntity is null

isOperatedOn

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public boolean isOperatedOn(Object mergeEntity)

Returns true if the listener is performing the merge operation on the specified merge entity.

Parameters

mergeEntity:Object: the merge entity; must be non-null

Returns:boolean

true if the listener is performing the merge operation on the specified merge entity; false, if there is no mapping for mergeEntity.

Exceptions

NullPointerException:: if mergeEntity is null

keySet back to summary

keySet	back to summary
public Set<Object> keySet() Implements java.util.Map.keySet. Returns an unmodifiable set view of the merge entities contained in this MergeContext Returns:Set<Object> an unmodifiable set view of the merge entities contained in this MergeContext See Also `Collections#unmodifiableSet(Set)`

public Set<Object> keySet()

Implements java.util.Map.keySet.

Returns an unmodifiable set view of the merge entities contained in this MergeContext

Returns:Set<Object>: an unmodifiable set view of the merge entities contained in this MergeContext
See Also: Collections#unmodifiableSet(Set)

printEntity	back to summary
private String printEntity(Object entity)

put back to summary

put	back to summary
public Object put(Object mergeEntity, Object managedEntity) Implements java.util.Map.put. Associates the specified merge entity with the specified managed entity result in this MergeContext. If this MergeContext already contains a cross-reference for `mergeEntity` when this method is called, then `managedEntity` must be the same as what is already associated with `mergeEntity`. This method assumes that the merge process is not yet operating on `mergeEntity`. Later when `mergeEntity` enters the merge process, `setOperatedOn(Object, boolean)` should be called. Parameters mergeEntity:Object the merge entity; must be non-null managedEntity:Object the managed entity result; must be non-null Returns:Object previous managed entity associated with specified merge entity, or null if there was no mapping for mergeEntity. Exceptions NullPointerException: if mergeEntity or managedEntity is null IllegalArgumentException: if `managedEntity` is not the same as the previous managed entity associated with `merge entity` IllegalStateException: if internal cross-references are out of sync,

public Object put(Object mergeEntity, Object managedEntity)

Implements java.util.Map.put.

Associates the specified merge entity with the specified managed entity result in this MergeContext. If this MergeContext already contains a cross-reference for mergeEntity when this method is called, then managedEntity must be the same as what is already associated with mergeEntity.

This method assumes that the merge process is not yet operating on mergeEntity. Later when mergeEntity enters the merge process, setOperatedOn(Object, boolean) should be called.

Parameters

mergeEntity:Object: the merge entity; must be non-null
managedEntity:Object: the managed entity result; must be non-null

Returns:Object

previous managed entity associated with specified merge entity, or null if there was no mapping for mergeEntity.

Exceptions

NullPointerException:: if mergeEntity or managedEntity is null
IllegalArgumentException:: if managedEntity is not the same as the previous managed entity associated with merge entity
IllegalStateException:: if internal cross-references are out of sync,

put back to summary

put	back to summary
public Object put(Object mergeEntity, Object managedEntity, boolean isOperatedOn) Associates the specified merge entity with the specified managed entity in this MergeContext. If this MergeContext already contains a cross-reference for `mergeEntity` when this method is called, then `managedEntity` must be the same as what is already associated with `mergeEntity`. Parameters mergeEntity:Object the merge entity; must be non-null managedEntity:Object the managed entity; must be non-null isOperatedOn:boolean indicates if the merge operation is performed on the mergeEntity. Returns:Object previous managed entity associated with specified merge entity, or null if there was no mapping for mergeEntity. Exceptions NullPointerException: if mergeEntity or managedEntity is null IllegalArgumentException: if `managedEntity` is not the same as the previous managed entity associated with `mergeEntity` IllegalStateException: if internal cross-references are out of sync,

public Object put(Object mergeEntity, Object managedEntity, boolean isOperatedOn)

Associates the specified merge entity with the specified managed entity in this MergeContext. If this MergeContext already contains a cross-reference for mergeEntity when this method is called, then managedEntity must be the same as what is already associated with mergeEntity.

Parameters

mergeEntity:Object: the merge entity; must be non-null
managedEntity:Object: the managed entity; must be non-null
isOperatedOn:boolean: indicates if the merge operation is performed on the mergeEntity.

Returns:Object

previous managed entity associated with specified merge entity, or null if there was no mapping for mergeEntity.

Exceptions

NullPointerException:: if mergeEntity or managedEntity is null
IllegalArgumentException:: if managedEntity is not the same as the previous managed entity associated with mergeEntity
IllegalStateException:: if internal cross-references are out of sync,

putAll back to summary

putAll	back to summary
public void putAll(Map<?, ?> map) Implements java.util.Map.putAll. Copies all of the mappings from the specified Map to this MergeContext. The key and value for each entry in `map` is subject to the same restrictions as `put(Object mergeEntity, Object managedEntity)`. This method assumes that the merge process is not yet operating on any merge entity Parameters map:Map<?, ?> keys and values must be non-null Exceptions NullPointerException: if any key or value is null IllegalArgumentException: if a key in `map` was already in this MergeContext but associated value in `map` is different from the previous value in this MergeContext. IllegalStateException: if internal cross-references are out of sync,

public void putAll(Map<?, ?> map)

Implements java.util.Map.putAll.

Copies all of the mappings from the specified Map to this MergeContext. The key and value for each entry in map is subject to the same restrictions as put(Object mergeEntity, Object managedEntity). This method assumes that the merge process is not yet operating on any merge entity

Parameters

map:Map<?, ?>: keys and values must be non-null

Exceptions

NullPointerException:: if any key or value is null
IllegalArgumentException:: if a key in map was already in this MergeContext but associated value in map is different from the previous value in this MergeContext.
IllegalStateException:: if internal cross-references are out of sync,

remove back to summary

remove	back to summary
public Object remove(Object mergeEntity) Implements java.util.Map.remove. The remove operation is not supported. Parameters mergeEntity:Object the merge entity. Returns:Object Doc from java.util.Map.remove. the previous value associated with `key`, or `null` if there was no mapping for `key`. Exceptions UnsupportedOperationException: if called.

public Object remove(Object mergeEntity)

Implements java.util.Map.remove.

The remove operation is not supported.

Parameters

mergeEntity:Object: the merge entity.

Returns:Object

Doc from java.util.Map.remove.

the previous value associated with key, or null if there was no mapping for key.

Exceptions

UnsupportedOperationException:: if called.

setOperatedOn	back to summary
public void setOperatedOn(Object mergeEntity, boolean isOperatedOn) Set flag to indicate if the listener is performing the merge operation on the specified merge entity. Parameters mergeEntity:Object must be non-null and this MergeContext must contain a cross-reference for mergeEntity to a managed entity Exceptions NullPointerException: if mergeEntity is null IllegalStateException: if this MergeContext does not contain a a cross-reference for mergeEntity

setOperatedOn

back to summary

public void setOperatedOn(Object mergeEntity, boolean isOperatedOn)

Set flag to indicate if the listener is performing the merge operation on the specified merge entity.

Parameters

mergeEntity:Object: must be non-null and this MergeContext must contain a cross-reference for mergeEntity to a managed entity

Exceptions

NullPointerException:: if mergeEntity is null
IllegalStateException:: if this MergeContext does not contain a a cross-reference for mergeEntity

size	back to summary
public int size() Implements java.util.Map.size. Returns the number of merge-to-managed entity cross-references in this MergeContext Returns:int the number of merge-to-managed entity cross-references in this MergeContext

size

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public int size()

Implements java.util.Map.size.

Returns the number of merge-to-managed entity cross-references in this MergeContext

Returns:int: the number of merge-to-managed entity cross-references in this MergeContext

values back to summary

values	back to summary
public Collection<Object> values() Implements java.util.Map.values. Returns an unmodifiable Set view of managed entities contained in this MergeContext. Returns:Collection<Object> an unmodifiable Set view of managed entities contained in this MergeContext See Also `Collections#unmodifiableSet(Set)`

public Collection<Object> values()

Implements java.util.Map.values.

Returns an unmodifiable Set view of managed entities contained in this MergeContext.

Returns:Collection<Object>: an unmodifiable Set view of managed entities contained in this MergeContext
See Also: Collections#unmodifiableSet(Set)

public Class MergeContext

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail