com.bigdata.rdf.model
Class BigdataValueFactoryImpl

java.lang.Object
  com.bigdata.rdf.model.BigdataValueFactoryImpl

All Implemented Interfaces:

BigdataValueFactory, ValueFactory

public class BigdataValueFactoryImpl
extends Object
implements BigdataValueFactory

An implementation using BigdataValues and BigdataStatements. Values constructed using this factory do NOT have term identifiers assigned. Statements constructed using this factory do NOT have statement identifiers assigned. Those metadata can be resolved against the various indices and then set on the returned values and statements.

Version:

$Id: BigdataValueFactoryImpl.java 6036 2012-02-17 14:07:48Z thompsonbry $

Author:

Bryan Thompson

TODO:

Consider a WeakValueCache on this factory to avoid duplicate values., Consider a WeakValueCache to shortcut recently used statements?

Field Summary

static String	NAMESPACE_XSD
static String	xsd

Method Summary

BigdataBNode	asValue(BNode v) Strongly typed for BNodes.
BigdataLiteral	asValue(Literal v) Strongly typed for Literals.
BigdataResource	asValue(Resource v) Strongly typed for Resources.
BigdataURI	asValue(URI v) Strongly typed for URIs.
BigdataValue	asValue(Value v) Converts a Value into a BigdataValue.
BigdataBNodeImpl	createBNode() Returns a new blank node with a globally unique blank node ID based on a UUID.
BigdataBNodeImpl	createBNode(String id)
BigdataLiteralImpl	createLiteral(boolean arg0)
BigdataLiteralImpl	createLiteral(byte arg0)
BigdataLiteralImpl	createLiteral(byte arg0, boolean unsigned)
BigdataLiteralImpl	createLiteral(double arg0)
BigdataLiteralImpl	createLiteral(float arg0)
BigdataLiteralImpl	createLiteral(int arg0)
BigdataLiteralImpl	createLiteral(int arg0, boolean unsigned)
BigdataLiteralImpl	createLiteral(long arg0)
BigdataLiteralImpl	createLiteral(long arg0, boolean unsigned)
BigdataLiteralImpl	createLiteral(short arg0)
BigdataLiteralImpl	createLiteral(short arg0, boolean unsigned)
BigdataLiteralImpl	createLiteral(String label)
BigdataLiteralImpl	createLiteral(String label, String language)
BigdataLiteralImpl	createLiteral(String label, URI datatype)
BigdataLiteralImpl	createLiteral(XMLGregorianCalendar arg0)
BigdataStatementImpl	createStatement(Resource s, URI p, Value o) Create a statement whose StatementEnum is NOT specified.
BigdataStatementImpl	createStatement(Resource s, URI p, Value o, Resource c) Create a statement whose StatementEnum is NOT specified.
BigdataStatementImpl	createStatement(Resource s, URI p, Value o, Resource c, StatementEnum type) Create a statement (core impl).
BigdataStatementImpl	createStatement(Resource s, URI p, Value o, Resource c, StatementEnum type, boolean userFlag) Create a statement (core impl).
BigdataURIImpl	createURI(String uriString)
BigdataURIImpl	createURI(String namespace, String localName)
static BigdataValueFactory	getInstance(String namespace) Return the instance associated with the namespace.
String	getNamespace() The namespace of the KB instance associated with the value factory.
BigdataValueSerializer<BigdataValue>	getValueSerializer() An object that can efficiently (de-)serialize Values using this ValueFactory.
BNodeContextFactory	newBNodeContext() Returns a factory that will assign its blank node IDs within a globally unique namespace.
protected String	nextID() Returns a blank node identifier (ID) based on a random UUID.
void	remove() Remove a BigdataValueFactoryImpl from the canonicalizing mapping.

Methods inherited from class java.lang.Object

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

Field Detail

NAMESPACE_XSD

public static final transient String NAMESPACE_XSD

See Also:

Constant Field Values

xsd

public static final transient String xsd

See Also:

Constant Field Values

Method Detail

getNamespace

public String getNamespace()

Description copied from interface: BigdataValueFactory

The namespace of the KB instance associated with the value factory.

Specified by:

getNamespace in interface BigdataValueFactory

getInstance

public static BigdataValueFactory getInstance(String namespace)

Return the instance associated with the namespace.

Note: This canonicalizing mapping for BigdataValueFactoryImpls is based on the namespace of the LexiconRelation. This makes the instances canonical within a JVM instance, which is all that we care about. The actual assignments of term identifiers to BigdataValue s is performed by the LexiconRelation itself and is globally consistent for a given lexicon.

Parameters:

namespace - The namespace of the LexiconRelation. TODO This method introduces the possibility that two journals in the same JVM would share the same BigdataValueFactory for a kb with the same namespace. This is doubtless not desired. A workaround is to use the UUID of the Journal as part of the namespace of the KB, which would serve to make sure that all KB instances have distinct namespaces.

remove

public void remove()

Remove a BigdataValueFactoryImpl from the canonicalizing mapping.

Entries in this canonicalizing mapping for a LexiconRelation MUST be #remove(String)ed if the LexiconRelation is destroyed in case a distinct lexicon is subsequently creating with the same namespace. There is no need to discard an entry during abort processing.

Specified by:

remove in interface BigdataValueFactory

newBNodeContext

public BNodeContextFactory newBNodeContext()

Description copied from interface: BigdataValueFactory

Returns a factory that will assign its blank node IDs within a globally unique namespace. This factory should be used when processing a document as the generated IDs are clustered and make the ordered writes on the lexicon more efficient since all blank nodes for the same document tend to be directed to the same index partition. All BigdataValues are actually created by this factory, it is only the semantics of blank node ID generation that are overridden.

Specified by:

newBNodeContext in interface BigdataValueFactory

See Also:

BNodeContextFactory

createBNode

public BigdataBNodeImpl createBNode()

Returns a new blank node with a globally unique blank node ID based on a UUID.

Note: Since the blank node IDs are random, they tend to be uniformly distributed across the index partition(s). More efficient ordered writes may be realized using newBNodeContext() to obtain a derived BigdataValueFactory instance that is specific to a document that is being loaded into the RDF DB.

Specified by:

createBNode in interface BigdataValueFactory

Specified by:

createBNode in interface ValueFactory

See Also:

newBNodeContext()

nextID

protected String nextID()

Returns a blank node identifier (ID) based on a random UUID.

createBNode

public BigdataBNodeImpl createBNode(String id)

Specified by:

createBNode in interface BigdataValueFactory

Specified by:

createBNode in interface ValueFactory

createLiteral

public BigdataLiteralImpl createLiteral(String label)

Specified by:

createLiteral in interface BigdataValueFactory

Specified by:

createLiteral in interface ValueFactory

createLiteral

public BigdataLiteralImpl createLiteral(boolean arg0)

Specified by:

createLiteral in interface BigdataValueFactory

Specified by:

createLiteral in interface ValueFactory

createLiteral

public BigdataLiteralImpl createLiteral(byte arg0)

Specified by:

createLiteral in interface BigdataValueFactory

Specified by:

createLiteral in interface ValueFactory

createLiteral

public BigdataLiteralImpl createLiteral(byte arg0,
                                        boolean unsigned)

Specified by:

createLiteral in interface BigdataValueFactory

createLiteral

public BigdataLiteralImpl createLiteral(short arg0)

Specified by:

createLiteral in interface BigdataValueFactory

Specified by:

createLiteral in interface ValueFactory

createLiteral

public BigdataLiteralImpl createLiteral(short arg0,
                                        boolean unsigned)

Specified by:

createLiteral in interface BigdataValueFactory

createLiteral

public BigdataLiteralImpl createLiteral(int arg0)

Specified by:

createLiteral in interface BigdataValueFactory

Specified by:

createLiteral in interface ValueFactory

createLiteral

public BigdataLiteralImpl createLiteral(int arg0,
                                        boolean unsigned)

Specified by:

createLiteral in interface BigdataValueFactory

createLiteral

public BigdataLiteralImpl createLiteral(long arg0)

Specified by:

createLiteral in interface BigdataValueFactory

Specified by:

createLiteral in interface ValueFactory

createLiteral

public BigdataLiteralImpl createLiteral(long arg0,
                                        boolean unsigned)

Specified by:

createLiteral in interface BigdataValueFactory

createLiteral

public BigdataLiteralImpl createLiteral(float arg0)

Specified by:

createLiteral in interface BigdataValueFactory

Specified by:

createLiteral in interface ValueFactory

createLiteral

public BigdataLiteralImpl createLiteral(double arg0)

Specified by:

createLiteral in interface BigdataValueFactory

Specified by:

createLiteral in interface ValueFactory

createLiteral

public BigdataLiteralImpl createLiteral(XMLGregorianCalendar arg0)

Specified by:

createLiteral in interface BigdataValueFactory

Specified by:

createLiteral in interface ValueFactory

createLiteral

public BigdataLiteralImpl createLiteral(String label,
                                        String language)

Specified by:

createLiteral in interface BigdataValueFactory

Specified by:

createLiteral in interface ValueFactory

createLiteral

public BigdataLiteralImpl createLiteral(String label,
                                        URI datatype)

Specified by:

createLiteral in interface BigdataValueFactory

Specified by:

createLiteral in interface ValueFactory

createURI

public BigdataURIImpl createURI(String uriString)

Specified by:

createURI in interface BigdataValueFactory

Specified by:

createURI in interface ValueFactory

createURI

public BigdataURIImpl createURI(String namespace,
                                String localName)

Specified by:

createURI in interface BigdataValueFactory

Specified by:

createURI in interface ValueFactory

createStatement

public BigdataStatementImpl createStatement(Resource s,
                                            URI p,
                                            Value o)

Description copied from interface: BigdataValueFactory

Create a statement whose StatementEnum is NOT specified.

Specified by:

createStatement in interface BigdataValueFactory

Specified by:

createStatement in interface ValueFactory

createStatement

public BigdataStatementImpl createStatement(Resource s,
                                            URI p,
                                            Value o,
                                            Resource c)

Description copied from interface: BigdataValueFactory

Create a statement whose StatementEnum is NOT specified.

Specified by:

createStatement in interface BigdataValueFactory

Specified by:

createStatement in interface ValueFactory

createStatement

public BigdataStatementImpl createStatement(Resource s,
                                            URI p,
                                            Value o,
                                            Resource c,
                                            StatementEnum type)

Description copied from interface: BigdataValueFactory

Create a statement (core impl). The s,p,o, and the optional c arguments will be normalized to this BigdataValueFactory using BigdataValueFactory.asValue(Value).

Specified by:

createStatement in interface BigdataValueFactory

Parameters:

s - The subject.

p - The predicate.

o - The object.

c - The context (optional). Note: When non-null and statement identifiers are enabled, then this will be a blank node whose term identifier is the statement identifier.

type - The statement type (optional).

createStatement

public BigdataStatementImpl createStatement(Resource s,
                                            URI p,
                                            Value o,
                                            Resource c,
                                            StatementEnum type,
                                            boolean userFlag)

Description copied from interface: BigdataValueFactory

Create a statement (core impl). The s,p,o, and the optional c arguments will be normalized to this BigdataValueFactory using BigdataValueFactory.asValue(Value).

Specified by:

createStatement in interface BigdataValueFactory

Parameters:

s - The subject.

p - The predicate.

o - The object.

c - The context (optional). Note: When non-null and statement identifiers are enabled, then this will be a blank node whose term identifier is the statement identifier.

type - The statement type (optional).

userFlag - The user flag

asValue

public final BigdataValue asValue(Value v)

Description copied from interface: BigdataValueFactory

Converts a Value into a BigdataValue. If the value is already a BigdataValue and it was allocated by this BigdataValueFactoryImpl then it is returned unchanged. Otherwise a new BigdataValue will be creating using the same data as the given value and the term identifier on the new BigdataValue will be initialized to IRawTripleStore#NULL.

All BigdataValues created by a BigdataValueFactoryImpl internally store a transient reference to the BigdataValueFactoryImpl. This reference is used to decide if a BigdataValue MIGHT have been created by a different lexicon (term identifiers generated by different lexicons CAN NOT be used interchangeably). This has the effect of protecting against incorrect use of the term identifier with a database backed by a different lexicon while allowing reuse of the BigdataValues when possible.

Specified by:

asValue in interface BigdataValueFactory

Parameters:

v - The value.

Returns:

A BigdataValue with the same data. If the value is null then null is returned.

getValueSerializer

public BigdataValueSerializer<BigdataValue> getValueSerializer()

Description copied from interface: BigdataValueFactory

An object that can efficiently (de-)serialize Values using this ValueFactory. When the values are de-serialized they will have a reference to this BigdataValueFactoryImpl. That reference can be used to identify when two BigdataValues MIGHT be from different lexicons.

Specified by:

getValueSerializer in interface BigdataValueFactory

Returns:

asValue

public BigdataResource asValue(Resource v)

Description copied from interface: BigdataValueFactory

Strongly typed for Resources.

Specified by:

asValue in interface BigdataValueFactory

asValue

public BigdataURI asValue(URI v)

Description copied from interface: BigdataValueFactory

Strongly typed for URIs.

Specified by:

asValue in interface BigdataValueFactory

asValue

public BigdataLiteral asValue(Literal v)

Description copied from interface: BigdataValueFactory

Strongly typed for Literals.

Specified by:

asValue in interface BigdataValueFactory

asValue

public BigdataBNode asValue(BNode v)

Description copied from interface: BigdataValueFactory

Strongly typed for BNodes.

Specified by:

asValue in interface BigdataValueFactory