com.thinkaurelius.titan.core

Interface TitanElement

All Superinterfaces:

Comparable<TitanElement>, com.tinkerpop.blueprints.Element, Idfiable, Removable

All Known Subinterfaces:

EdgeLabel, InternalElement, InternalRelation, InternalRelationType, InternalVertex, InternalVertexLabel, PropertyKey, RelationType, SystemRelationType, TitanEdge, TitanProperty, TitanRelation, TitanVertex, VertexLabel

All Known Implementing Classes:

AbstractEdge, AbstractElement, AbstractProperty, AbstractTypedRelation, AbstractVertex, BaseKey, BaseLabel, BaseRelationType, BaseVertexLabel, CacheEdge, CacheProperty, CacheVertex, EdgeLabelVertex, EmptyRelationType, EmptyVertex, FulgoraNeighborVertex, FulgoraVertex, ImplicitKey, PropertyKeyVertex, RelationTypeVertex, StandardEdge, StandardProperty, StandardVertex, TitanSchemaVertex, VertexLabelVertex

public interface TitanElement
extends com.tinkerpop.blueprints.Element, Idfiable, Comparable<TitanElement>, Removable

TitanElement represents the abstract concept of an entity in the graph and specifies basic methods for interacting with entities. The two basic entities in a graph database are TitanRelation and TitanVertex. Entities have a life cycle state which reflects the current state of the entity with respect to the TitanTransaction in which it occurs. An entity may be in any one of these states and any given time:

• New: The entity has been created in the current transaction
• Loaded: The entity has been loaded from disk into the current transaction and has not been modified
• Modified: The entity has been loaded from disk into the current transaction and has been modified
• Deleted: The entity has been deleted in the current transaction

Depending on the concrete type of the entity, an entity may be identifiable, i.e. it has a unique ID which can be retrieved via getId() (use hasId() to determine if a given entity has a unique ID).

Author:

Matthias Bröcheler (http://www.matthiasb.com)

See Also:

TitanVertex, TitanRelation

Method Summary

Methods

Modifier and Type	Method and Description
Object	getId() Returns a unique identifier for this entity.
long	getID() Unique identifier for this entity.
<O> O	getProperty(PropertyKey key) Retrieves the value associated with the given key on this vertex and casts it to the specified type.
<O> O	getProperty(String key) Retrieves the value associated with the given key on this vertex and casts it to the specified type.
boolean	hasId() Checks whether this entity has a unique identifier.
boolean	isLoaded() Checks whether this entity has been loaded into the current transaction and not yet modified.
boolean	isNew() Checks whether this entity has been newly created in the current transaction.
boolean	isRemoved() Checks whether this entity has been deleted into the current transaction.
void	remove() Deletes this entity and any incident edges or properties from the graph.
<O> O	removeProperty(RelationType type) Removes the value associated with the given key for this vertex (if exists).
<O> O	removeProperty(String key) Removes the value associated with the given key for this vertex (if exists).
void	setProperty(PropertyKey key, Object value) Sets the value for the given key on this element.
void	setProperty(String key, Object value) Sets the value for the given key on this element.

Methods inherited from interface com.tinkerpop.blueprints.Element

getPropertyKeys

Methods inherited from interface java.lang.Comparable

compareTo

Method Detail

getId

Object getId()

Returns a unique identifier for this entity.

The unique identifier may only be set when the transaction in which entity is created commits. The Graph Configuration Wiki explains how to configure when entity ids are assigned. Some entities are never assigned a unique identifier if they depend on a parent entity.

Specified by:

getId in interface com.tinkerpop.blueprints.Element

Returns:

The unique identifier for this entity

Throws:

IllegalStateException - if the entity does not (yet) have a unique identifier

See Also:

hasId()

getID

long getID()

Unique identifier for this entity. This id can be temporarily assigned and might change. Use getId() for the permanent id.

Specified by:

getID in interface Idfiable

Returns:

Unique long id

hasId

boolean hasId()

Checks whether this entity has a unique identifier.

Note that some entities may never be assigned an identifier and others will only be assigned an identifier at the end of a transaction.

Returns:

true if this entity has been assigned a unique id, else false

See Also:

getID()

remove

void remove()

Deletes this entity and any incident edges or properties from the graph.

Specified by:

remove in interface com.tinkerpop.blueprints.Element

Specified by:

remove in interface Removable

Throws:

IllegalStateException - if the entity cannot be deleted or if the user does not have permission to remove the entity

setProperty

void setProperty(String key,
               Object value)

Sets the value for the given key on this element. The key must be defined to have Cardinality.SINGLE, otherwise this method throws an exception.

Specified by:

setProperty in interface com.tinkerpop.blueprints.Element

Parameters:

key - the string identifying the key

value - the object value

setProperty

void setProperty(PropertyKey key,
               Object value)

Sets the value for the given key on this element. The key must be defined to have Cardinality.SINGLE, otherwise this method throws an exception.

Parameters:

key - the key

value - the object value

getProperty

<O> O getProperty(PropertyKey key)

Retrieves the value associated with the given key on this vertex and casts it to the specified type. If the key has cardinality SINGLE, then there can be at most one value and this value is returned (or null). Otherwise a list of all associated values is returned, or an empty list if non exist.

Parameters:

key - key

Returns:

value or list of values associated with key

getProperty

<O> O getProperty(String key)

Retrieves the value associated with the given key on this vertex and casts it to the specified type. If the key has cardinality SINGLE, then there can be at most one value and this value is returned (or null). Otherwise a list of all associated values is returned, or an empty list if non exist.

Specified by:

getProperty in interface com.tinkerpop.blueprints.Element

Parameters:

key - string identifying a key

Returns:

value or list of values associated with key

removeProperty

<O> O removeProperty(String key)

Removes the value associated with the given key for this vertex (if exists).

Specified by:

removeProperty in interface com.tinkerpop.blueprints.Element

Parameters:

key - the string identifying the key

Returns:

the object value associated with that key prior to removal, or NULL if such does not exist.

See Also:

removeProperty(RelationType)

removeProperty

<O> O removeProperty(RelationType type)

Removes the value associated with the given key for this vertex (if exists). If the key is list-valued then all values associated with this key are removed and only the last removed value returned.

Parameters:

type - the key

Returns:

the object value associated with that key prior to removal, or NULL if such does not exist.

isNew

boolean isNew()

Checks whether this entity has been newly created in the current transaction.

Returns:

True, if entity has been newly created, else false.

isLoaded

boolean isLoaded()

Checks whether this entity has been loaded into the current transaction and not yet modified.

Returns:

True, has been loaded and not modified, else false.

isRemoved

boolean isRemoved()

Checks whether this entity has been deleted into the current transaction.

Returns:

True, has been deleted, else false.