com.graphaware.tx.event.improved.api

Interface ImprovedTransactionData

All Superinterfaces:

TransactionDataWrapper, Wrapper<org.neo4j.graphdb.event.TransactionData>

All Known Implementing Classes:

FilteredTransactionData, LazyTransactionData

public interface ImprovedTransactionData
extends TransactionDataWrapper

Within the context of a running transaction, this API gives users the ability to find out exactly what mutations occurred on the graph during that transaction. Used in the same context as TransactionData, i.e. before or after a transaction commit, this API improves the TransactionData API in a number of ways.

It categorizes Entitys, i.e. Nodes and Relationships into:

• created in this transaction
• deleted in this transaction
• changed in this transaction, i.e those with at least one property created, deleted, or changed
• untouched by this transaction

Users can find out, whether a Entity has been created, deleted, or changed in this transaction and obtain all the created, deleted, and changed Entitys.

Properties that have been created, deleted, and changed in the transaction are grouped by the changed Entity they belong to. Users can find out, which properties have been created, deleted, and changed for a given changed Entity and check, whether a given property for a given changed Entity has been created, deleted, or changed.

Properties of created Entitys are available through the actual created Entity. Properties of deleted Entitys (as they were before the transaction started) are available through the snapshot of the deleted Entity, obtained by calling getDeleted(org.neo4j.graphdb.Node) or getDeleted(org.neo4j.graphdb.Relationship). Properties of created and deleted entities will not be returned by changedProperties(org.neo4j.graphdb.Node) and changedProperties(org.neo4j.graphdb.Relationship) as these only return changed properties of changed Entitys.

Changed Entitys and properties are wrapped in a Change object which holds the previous state of the object before the transaction started, and the current state of the object (when the transaction commits).

All created Entitys + properties and current versions of changed Entitys + properties can be accessed by native Neo4j API and the traversal API as one would expect. For example, one can traverse the graph starting from a newly created node, using a mixture of newly created and already existing relationships. In other words, one can traverse the graph as if the transaction has already been committed. This is similar to using TransactionData.

A major difference between this API and TransactionData, however, is what one can do with the returned information about deleted Entitys + properties and the previous versions thereof. With this API, one can traverse a snapshot of the graph as it was before the transaction started. As opposed to the TransactionData API, this will not result in exceptions being thrown.

For example, one can start traversing the graph from a deleted Node, or the previous version of a changed Node. Such traversal will only traverse Relationships that existed before the transaction started and will return properties and their values as they were before the transaction started. This is achieved using NodeSnapshot and RelationshipSnapshot decorators.

One can even perform additional mutating operations on the previous version (snapshot) of the graph, provided that the mutated objects have been changed in the transaction (as opposed to deleted). Mutating deleted Entitys and properties does not make any sense and will cause exceptions.

To summarize, this API gives access to two versions of the same graph. Through created Entitys and/or their current versions, one can traverse the current version of the graph as it will be after the transaction commits. Through deleted and/or previous versions of Entitys, one can traverse the previous snapshot of the graph, as it was before the transaction started.

Method Summary

Modifier and Type	Method and Description
Set<org.neo4j.graphdb.Label>	assignedLabels(org.neo4j.graphdb.Node node) Get labels assigned in the transaction.
Map<String,Change<Object>>	changedProperties(org.neo4j.graphdb.Node node) Get properties changed in the transaction.
Map<String,Change<Object>>	changedProperties(org.neo4j.graphdb.Relationship relationship) Get properties changed in the transaction.
Map<String,Object>	createdProperties(org.neo4j.graphdb.Node node) Get properties created in the transaction.
Map<String,Object>	createdProperties(org.neo4j.graphdb.Relationship relationship) Get properties created in the transaction.
Map<String,Object>	deletedProperties(org.neo4j.graphdb.Node node) Get properties deleted in the transaction.
Map<String,Object>	deletedProperties(org.neo4j.graphdb.Relationship relationship) Get properties deleted in the transaction.
Collection<Change<org.neo4j.graphdb.Node>>	getAllChangedNodes() Get all nodes changed in the transaction.
Collection<Change<org.neo4j.graphdb.Relationship>>	getAllChangedRelationships() Get all relationships changed in the transaction.
Collection<org.neo4j.graphdb.Node>	getAllCreatedNodes() Get all nodes created in the transaction.
Collection<org.neo4j.graphdb.Relationship>	getAllCreatedRelationships() Get all relationships created in the transaction.
Collection<org.neo4j.graphdb.Node>	getAllDeletedNodes() Get all nodes deleted in the transaction as they were before the transaction started.
Collection<org.neo4j.graphdb.Relationship>	getAllDeletedRelationships() Get all relationships deleted in the transaction as they were before the transaction started.
Change<org.neo4j.graphdb.Node>	getChanged(org.neo4j.graphdb.Node node) Get a node that has been changed in this transaction as it was before the transaction started and as it is now.
Change<org.neo4j.graphdb.Relationship>	getChanged(org.neo4j.graphdb.Relationship relationship) Get a relationship that has been changed in this transaction as it was before the transaction started and as it is now.
org.neo4j.graphdb.Node	getDeleted(org.neo4j.graphdb.Node node) Get a node that has been deleted in this transaction as it was before the transaction started.
org.neo4j.graphdb.Relationship	getDeleted(org.neo4j.graphdb.Relationship relationship) Get a relationship that has been deleted in this transaction as it was before the transaction started.
Collection<org.neo4j.graphdb.Relationship>	getDeletedRelationships(org.neo4j.graphdb.Node node, org.neo4j.graphdb.Direction direction, org.neo4j.graphdb.RelationshipType... types) Get all relationships for the given node and of the given directions and types, which have been deleted in the transaction.
Collection<org.neo4j.graphdb.Relationship>	getDeletedRelationships(org.neo4j.graphdb.Node node, org.neo4j.graphdb.RelationshipType... types) Get all relationships for the given node and of the given types, which have been deleted in the transaction.
boolean	hasBeenChanged(org.neo4j.graphdb.Node node) Check whether a node has been changed in the transaction, i.e.
boolean	hasBeenChanged(org.neo4j.graphdb.Relationship relationship) Check whether a relationship has been changed in the transaction, i.e.
boolean	hasBeenCreated(org.neo4j.graphdb.Node node) Check whether the given node has been created in the transaction.
boolean	hasBeenCreated(org.neo4j.graphdb.Relationship relationship) Check whether the given relationship has been created in the transaction.
boolean	hasBeenDeleted(org.neo4j.graphdb.Node node) Check whether the given node has been deleted in the transaction.
boolean	hasBeenDeleted(org.neo4j.graphdb.Relationship relationship) Check whether the given relationship has been deleted in the transaction.
boolean	hasLabelBeenAssigned(org.neo4j.graphdb.Node node, org.neo4j.graphdb.Label label) Check whether a label has been assigned in the transaction.
boolean	hasLabelBeenRemoved(org.neo4j.graphdb.Node node, org.neo4j.graphdb.Label label) Check whether a label has been removed in the transaction.
boolean	hasPropertyBeenChanged(org.neo4j.graphdb.Node node, String key) Check whether a property has been changed in the transaction.
boolean	hasPropertyBeenChanged(org.neo4j.graphdb.Relationship relationship, String key) Check whether a property has been changed in the transaction.
boolean	hasPropertyBeenCreated(org.neo4j.graphdb.Node node, String key) Check whether a property has been created in the transaction.
boolean	hasPropertyBeenCreated(org.neo4j.graphdb.Relationship relationship, String key) Check whether a property has been created in the transaction.
boolean	hasPropertyBeenDeleted(org.neo4j.graphdb.Node node, String key) Check whether a property has been deleted in the transaction.
boolean	hasPropertyBeenDeleted(org.neo4j.graphdb.Relationship relationship, String key) Check whether a property has been deleted in the transaction.
boolean	mutationsOccurred() Have any mutations actually occurred?
Set<String>	mutationsToStrings() Convert all mutations in the transaction to human-readable Strings.
Set<org.neo4j.graphdb.Label>	removedLabels(org.neo4j.graphdb.Node node) Get labels removed in the transaction.

Methods inherited from interface com.graphaware.common.wrapper.Wrapper

getWrapped

Method Detail

hasBeenCreated

boolean hasBeenCreated(org.neo4j.graphdb.Node node)

Check whether the given node has been created in the transaction.

Parameters:

node - to check.

Returns:

true iff the node has been created.

getAllCreatedNodes

Collection<org.neo4j.graphdb.Node> getAllCreatedNodes()

Get all nodes created in the transaction.

Returns:

read-only collection of all created nodes.

hasBeenDeleted

boolean hasBeenDeleted(org.neo4j.graphdb.Node node)

Check whether the given node has been deleted in the transaction.

Parameters:

node - to check.

Returns:

true iff the node has been deleted.

getDeleted

org.neo4j.graphdb.Node getDeleted(org.neo4j.graphdb.Node node)

Get a node that has been deleted in this transaction as it was before the transaction started.

Parameters:

node - to get.

Returns:

snapshot of the node before the transaction started.

Throws:

IllegalArgumentException - in case the given node has not been deleted in the transaction.

getAllDeletedNodes

Collection<org.neo4j.graphdb.Node> getAllDeletedNodes()

Get all nodes deleted in the transaction as they were before the transaction started.

Returns:

read-only collection of all deleted nodes as they were before the transaction started (snapshots).

hasBeenChanged

boolean hasBeenChanged(org.neo4j.graphdb.Node node)

Check whether a node has been changed in the transaction, i.e. if any of its properties have been changed.

Parameters:

node - to check.

Returns:

true iff the node has been changed.

getChanged

Change<org.neo4j.graphdb.Node> getChanged(org.neo4j.graphdb.Node node)

Get a node that has been changed in this transaction as it was before the transaction started and as it is now.

Parameters:

node - to get.

Returns:

snapshot of the node before the transaction started and the current state of the node.

Throws:

IllegalArgumentException - in case the given node has not been changed in the transaction.

getAllChangedNodes

Collection<Change<org.neo4j.graphdb.Node>> getAllChangedNodes()

Get all nodes changed in the transaction.

Returns:

a read-only collection of all changed nodes as they were before the transaction started and as they are now.

hasPropertyBeenCreated

boolean hasPropertyBeenCreated(org.neo4j.graphdb.Node node,
                               String key)

Check whether a property has been created in the transaction.

Parameters:

node - to check. Must be a changed Node, not a created one.

key - of the property to check.

Returns:

true iff the property has been created on the Node.

createdProperties

Map<String,Object> createdProperties(org.neo4j.graphdb.Node node)

Get properties created in the transaction.

Parameters:

node - for which to get created properties. Must be a changed Node, not a created one.

Returns:

read-only properties created for the given Node.

hasPropertyBeenDeleted

boolean hasPropertyBeenDeleted(org.neo4j.graphdb.Node node,
                               String key)

Check whether a property has been deleted in the transaction.

Parameters:

node - to check. Must be a changed Node, not a deleted one.

key - of the property to check.

Returns:

true iff the property has been deleted for the given Node.

deletedProperties

Map<String,Object> deletedProperties(org.neo4j.graphdb.Node node)

Get properties deleted in the transaction.

Parameters:

node - for which to get deleted properties. Must be a changed Node, not a deleted one.

Returns:

read-only properties deleted for the given Node, where the value is the property value before the transaction started.

hasPropertyBeenChanged

boolean hasPropertyBeenChanged(org.neo4j.graphdb.Node node,
                               String key)

Check whether a property has been changed in the transaction.

Parameters:

node - to check.

key - of the property to check.

Returns:

true iff the property has been changed.

changedProperties

Map<String,Change<Object>> changedProperties(org.neo4j.graphdb.Node node)

Get properties changed in the transaction.

Parameters:

node - for which to get changed properties.

Returns:

read-only properties changed for the given node, where the value is the property value before and after the transaction started, respectively.

hasLabelBeenAssigned

boolean hasLabelBeenAssigned(org.neo4j.graphdb.Node node,
                             org.neo4j.graphdb.Label label)

Check whether a label has been assigned in the transaction.

Parameters:

node - to check.

label - to check.

Returns:

true iff the node has been assigned.

assignedLabels

Set<org.neo4j.graphdb.Label> assignedLabels(org.neo4j.graphdb.Node node)

Get labels assigned in the transaction.

Parameters:

node - for which to get assigned labels.

Returns:

read-only labels created for the given node.

hasLabelBeenRemoved

boolean hasLabelBeenRemoved(org.neo4j.graphdb.Node node,
                            org.neo4j.graphdb.Label label)

Check whether a label has been removed in the transaction.

Parameters:

node - to check.

label - to check.

Returns:

true iff the label has been removed.

removedLabels

Set<org.neo4j.graphdb.Label> removedLabels(org.neo4j.graphdb.Node node)

Get labels removed in the transaction.

Parameters:

node - for which to get removed labels.

Returns:

read-only labels removed for the given node.

hasBeenCreated

boolean hasBeenCreated(org.neo4j.graphdb.Relationship relationship)

Check whether the given relationship has been created in the transaction.

Parameters:

relationship - to check.

Returns:

true iff the relationship has been created.

getAllCreatedRelationships

Collection<org.neo4j.graphdb.Relationship> getAllCreatedRelationships()

Get all relationships created in the transaction.

Returns:

read-only collection of all created relationships.

hasBeenDeleted

boolean hasBeenDeleted(org.neo4j.graphdb.Relationship relationship)

Check whether the given relationship has been deleted in the transaction.

Parameters:

relationship - to check.

Returns:

true iff the relationship has been deleted.

getDeleted

org.neo4j.graphdb.Relationship getDeleted(org.neo4j.graphdb.Relationship relationship)

Get a relationship that has been deleted in this transaction as it was before the transaction started.

Parameters:

relationship - to get.

Returns:

snapshot of the relationship before the transaction started.

Throws:

IllegalArgumentException - in case the given relationship has not been deleted in the transaction.

getAllDeletedRelationships

Collection<org.neo4j.graphdb.Relationship> getAllDeletedRelationships()

Get all relationships deleted in the transaction as they were before the transaction started.

Returns:

read-only collection of all deleted relationships as they were before the transaction started (snapshots).

getDeletedRelationships

Collection<org.neo4j.graphdb.Relationship> getDeletedRelationships(org.neo4j.graphdb.Node node,
                                                                   org.neo4j.graphdb.RelationshipType... types)

Get all relationships for the given node and of the given types, which have been deleted in the transaction.

Parameters:

node - for which to get deleted relationships.

types - of the deleted relationships. If no types are provided, all types are returned.

Returns:

snapshot of all deleted relationships for the given node of the given types, as they were before the transaction started.

getDeletedRelationships

Collection<org.neo4j.graphdb.Relationship> getDeletedRelationships(org.neo4j.graphdb.Node node,
                                                                   org.neo4j.graphdb.Direction direction,
                                                                   org.neo4j.graphdb.RelationshipType... types)

Get all relationships for the given node and of the given directions and types, which have been deleted in the transaction.

Parameters:

node - for which to get deleted relationships.

direction - of the deleted relationships

types - of the deleted relationships.

Returns:

snapshot of all deleted relationships for the given node of the given direction and types, as they were before the transaction started.

hasBeenChanged

boolean hasBeenChanged(org.neo4j.graphdb.Relationship relationship)

Check whether a relationship has been changed in the transaction, i.e. if any of its properties have been changed.

Parameters:

relationship - to check.

Returns:

true iff the relationship has been changed.

getChanged

Change<org.neo4j.graphdb.Relationship> getChanged(org.neo4j.graphdb.Relationship relationship)

Get a relationship that has been changed in this transaction as it was before the transaction started and as it is now.

Parameters:

relationship - to get.

Returns:

snapshot of the relationship before the transaction started and the current state of the relationship.

Throws:

IllegalArgumentException - in case the given relationship has not been changed in the transaction.

getAllChangedRelationships

Collection<Change<org.neo4j.graphdb.Relationship>> getAllChangedRelationships()

Get all relationships changed in the transaction.

Returns:

a read-only collection of all changed relationships as they were before the transaction started and as they are now.

hasPropertyBeenCreated

boolean hasPropertyBeenCreated(org.neo4j.graphdb.Relationship relationship,
                               String key)

Check whether a property has been created in the transaction.

Parameters:

relationship - to check. Must be a changed Relationship, not a created one.

key - of the property to check.

Returns:

true iff the property has been created for the Relationship.

createdProperties

Map<String,Object> createdProperties(org.neo4j.graphdb.Relationship relationship)

Get properties created in the transaction.

Parameters:

relationship - for which to get created properties. Must be a changed Node, not a created one.

Returns:

read-only properties created for the given changed Relationship.

hasPropertyBeenDeleted

boolean hasPropertyBeenDeleted(org.neo4j.graphdb.Relationship relationship,
                               String key)

Check whether a property has been deleted in the transaction.

Parameters:

relationship - to check. Must be a changed Relationship, not a deleted one.

key - of the property to check.

Returns:

true iff the property has been deleted for the given Relationship.

deletedProperties

Map<String,Object> deletedProperties(org.neo4j.graphdb.Relationship relationship)

Get properties deleted in the transaction.

Parameters:

relationship - for which to get deleted properties. Must be a changed Relationship, not a deleted one.

Returns:

read-only properties deleted for the given relationship, where the value is the property value before the transaction started.

hasPropertyBeenChanged

boolean hasPropertyBeenChanged(org.neo4j.graphdb.Relationship relationship,
                               String key)

Check whether a property has been changed in the transaction.

Parameters:

relationship - to check.

key - of the property to check.

Returns:

true iff the property has been changed.

changedProperties

Map<String,Change<Object>> changedProperties(org.neo4j.graphdb.Relationship relationship)

Get properties changed in the transaction.

Parameters:

relationship - for which to get changed properties.

Returns:

read-only properties changed for the given relationship, where the value is the property value before and after the transaction started, respectively.

mutationsOccurred

boolean mutationsOccurred()

Have any mutations actually occurred?

Returns:

true iff an least one of the following method calls returns a non-empty collection: getAllCreatedNodes(), getAllCreatedRelationships(), getAllDeletedNodes(), getAllDeletedRelationships(), getAllChangedNodes(), getAllChangedRelationships().

mutationsToStrings

Set<String> mutationsToStrings()

Convert all mutations in the transaction to human-readable Strings.

Returns:

human-readable Strings.