com.bigdata.rdf.sail.sparql

Class TriplePatternExprBuilder

java.lang.Object

com.bigdata.rdf.sail.sparql.ASTVisitorBase

com.bigdata.rdf.sail.sparql.BigdataASTVisitorBase

com.bigdata.rdf.sail.sparql.ValueExprBuilder

com.bigdata.rdf.sail.sparql.TriplePatternExprBuilder

All Implemented Interfaces:

SyntaxTreeBuilderVisitor

Direct Known Subclasses:

GroupGraphPatternBuilder

public class TriplePatternExprBuilder
extends ValueExprBuilder

Class handles triple patterns and property paths.

Version:

$Id$

Author:

Bryan Thompson

Field Summary

Fields inherited from class com.bigdata.rdf.sail.sparql.ValueExprBuilder

graphPattern

Fields inherited from class com.bigdata.rdf.sail.sparql.BigdataASTVisitorBase

context

Constructor Summary

Constructors

Constructor and Description
TriplePatternExprBuilder(BigdataASTContext context)

Method Summary

Methods

Modifier and Type	Method and Description
VarNode	visit(ASTBlankNodePropertyList node, Object data)
VarNode	visit(ASTCollection node, Object data) Handle the RDF Collection syntax.
List<TermNode>	visit(ASTObjectList node, Object data)
PathNode.PathAlternative	visit(ASTPathAlternative pathAltNode, Object data)
Object	visit(ASTPathElt pathEltNode, Object data)
Object	visit(ASTPathOneInPropertySet node, Object data)
PathNode.PathSequence	visit(ASTPathSequence pathSeqNode, Object data)
Object	visit(ASTPropertyList propListNode, Object data)
Object	visit(ASTPropertyListPath propListNode, Object data)
TermNode	visit(ASTTRefPattern node, Object data) This is invoked in two different contexts.

Methods inherited from class com.bigdata.rdf.sail.sparql.ValueExprBuilder

aggregate, binary, left, nary, noneary, quadary, right, ternary, unary, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit

Methods inherited from class com.bigdata.rdf.sail.sparql.BigdataASTVisitorBase

depth, firstASTGraphGraphAncestor, indent, indent, scopedGroupGraphPattern, visit, visit, visit, visit, visit, visit, visit, visit, visit

Methods inherited from class com.bigdata.rdf.sail.sparql.ASTVisitorBase

visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit

Methods inherited from class java.lang.Object

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

Constructor Detail

TriplePatternExprBuilder

public TriplePatternExprBuilder(BigdataASTContext context)

Parameters:

context -

Method Detail

visit

public final Object visit(ASTPropertyList propListNode,
           Object data)
                   throws VisitorException

Specified by:

visit in interface SyntaxTreeBuilderVisitor

Overrides:

visit in class ASTVisitorBase

Throws:

VisitorException

visit

public final Object visit(ASTPropertyListPath propListNode,
           Object data)
                   throws VisitorException

Specified by:

visit in interface SyntaxTreeBuilderVisitor

Overrides:

visit in class ASTVisitorBase

Throws:

VisitorException

visit

public PathNode.PathAlternative visit(ASTPathAlternative pathAltNode,
                             Object data)
                               throws VisitorException

Specified by:

visit in interface SyntaxTreeBuilderVisitor

Overrides:

visit in class ASTVisitorBase

Throws:

VisitorException

visit

public PathNode.PathSequence visit(ASTPathSequence pathSeqNode,
                          Object data)
                            throws VisitorException

Specified by:

visit in interface SyntaxTreeBuilderVisitor

Overrides:

visit in class ASTVisitorBase

Throws:

VisitorException

visit

public Object visit(ASTPathElt pathEltNode,
           Object data)
             throws VisitorException

Specified by:

visit in interface SyntaxTreeBuilderVisitor

Overrides:

visit in class ASTVisitorBase

Throws:

VisitorException

visit

public Object visit(ASTPathOneInPropertySet node,
           Object data)
             throws VisitorException

Specified by:

visit in interface SyntaxTreeBuilderVisitor

Overrides:

visit in class ASTVisitorBase

Throws:

VisitorException

visit

public final List<TermNode> visit(ASTObjectList node,
                   Object data)
                           throws VisitorException

Specified by:

visit in interface SyntaxTreeBuilderVisitor

Overrides:

visit in class ASTVisitorBase

Throws:

VisitorException

visit

public final VarNode visit(ASTBlankNodePropertyList node,
            Object data)
                    throws VisitorException

Specified by:

visit in interface SyntaxTreeBuilderVisitor

Overrides:

visit in class ASTVisitorBase

Throws:

VisitorException

visit

public VarNode visit(ASTCollection node,
            Object data)
              throws VisitorException

Handle the RDF Collection syntax.

Specified by:

visit in interface SyntaxTreeBuilderVisitor

Overrides:

visit in class ASTVisitorBase

Throws:

VisitorException

visit

public TermNode visit(ASTTRefPattern node,
             Object data)
               throws VisitorException

This is invoked in two different contexts. One for a bare triple reference pattern:

 <> d e
 

and the other for a BIND() of a triple reference pattern onto a statement identifier variable:

 BIND(<> as ?sidVar)
 

In both cases we translate the triple reference pattern into a new StatementPatternNode. We reach back to the parent to decide which of the two invocation contexts applies and either generate a new SID variable or use the one from the BIND(). Then we set the SID variable on the StatementPatternNode and add it to the current graph pattern group.

If either the subject or object position in the triple reference pattern is a triple reference pattern, then it will have been turned into a StatementPatternNode by recursion through this method and we replace it with the SID variable which was assigned to that StatementPatternNode.

Specified by:

visit in interface SyntaxTreeBuilderVisitor

Overrides:

visit in class ASTVisitorBase

Returns:

The SID variable. This allows the existing code paths to handle nested triple reference patterns without change.

Throws:

VisitorException