com.bigdata.rdf.sail.sparql

Class BigdataASTContext

java.lang.Object

com.bigdata.rdf.sail.sparql.BigdataASTContext

public class BigdataASTContext
extends Object

Object provides context required in various stages of parsing queries or updates.

Author:

Bryan Thompson

Field Summary

Fields

Modifier and Type	Field and Description
protected BigdataValueFactory	valueFactory
protected Map<org.openrdf.model.Value,BigdataValue>	vocab A mapping of parsed RDF Values and well known vocabulary items used when generating the AST to resolved BigdataValues.

Constructor Summary

Constructors

Constructor and Description
BigdataASTContext(Map<org.openrdf.model.Value,BigdataValue> values)

Method Summary

Methods

Modifier and Type	Method and Description
protected VarNode	createAnonVar(String varName) Create an anonymous variable.
protected ConstantNode	createConstVar(org.openrdf.model.Value value) Return a constant for a pre-defined vocabulary item.
protected VarNode	createSidVar() Return a new variable for a SID (Statement Identifier)

Methods inherited from class java.lang.Object

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

Field Detail

valueFactory

protected final BigdataValueFactory valueFactory

vocab

protected final Map<org.openrdf.model.Value,BigdataValue> vocab

A mapping of parsed RDF Values and well known vocabulary items used when generating the AST to resolved BigdataValues. This includes everything which was parsed plus certain well-known items such as RDF.FIRST, RDF.REST, and RDF.NIL which are only used when handling syntactic sugar constructions.

Constructor Detail

BigdataASTContext

public BigdataASTContext(Map<org.openrdf.model.Value,BigdataValue> values)

Parameters:

values - A map from the distinct RDF Value objects in the QUERY or UPDATE request to the corresponding BigdataValue objects that will be used to process the request.

Method Detail

createAnonVar

protected VarNode createAnonVar(String varName)

Create an anonymous variable. The variable name will be unique (within the scope of the query parser) and VarNode.isAnonymous() will return true.

Parameters:

varName - The prefix of the name of an anonymous variable. This should have the pattern -foo-. An unique (within query) variable identifier will be appended to the prefix.

Returns:

The anonymous variable.

createConstVar

protected ConstantNode createConstVar(org.openrdf.model.Value value)
                               throws VisitorException

Return a constant for a pre-defined vocabulary item.

Throws:

VisitorException

createSidVar

protected VarNode createSidVar()

Return a new variable for a SID (Statement Identifier)

See Also:

Reification Done Right