org.eclipse.rdf4j.queryrender

Class BaseTupleExprRenderer

java.lang.Object

org.eclipse.rdf4j.query.algebra.helpers.AbstractQueryModelVisitor<Exception>

org.eclipse.rdf4j.queryrender.BaseTupleExprRenderer

All Implemented Interfaces:

QueryModelVisitor<Exception>

Direct Known Subclasses:

SparqlTupleExprRenderer

public abstract class BaseTupleExprRenderer
extends AbstractQueryModelVisitor<Exception>

Base class for rendering RDF4J query API objects into strings.

Author:

Michael Grove

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	mDistinct Whether or not the query is distinct
protected Map<String,ValueExpr>	mExtensions A map of the extensions specified in the query.
protected long	mLimit The limit of results for the query, or -1 for no limit
protected long	mOffset The query offset, or -1 for no offset
protected List<OrderElem>	mOrdering The elements specified in the order by clause of the query
protected List<ProjectionElemList>	mProjection The list of elements include in the projection of the query
protected boolean	mReduced Whether or not the query is reduced

Constructor Summary

Constructors

Constructor and Description
BaseTupleExprRenderer()

Method Summary

Modifier and Type	Method and Description
Map<String,ValueExpr>	getExtensions()
long	getLimit()
long	getOffset()
List<OrderElem>	getOrdering()
List<ProjectionElemList>	getProjection()
boolean	isDistinct()
boolean	isReduced()
protected boolean	isSelect() Returns whether or not the results of scanning the query model indicates that this represents a select query
static boolean	isSPOElemList(ProjectionElemList theList) Return whether or not this projection looks like an spo binding for a construct query
void	meet(Distinct theDistinct)
void	meet(ExtensionElem theExtensionElem)
void	meet(OrderElem theOrderElem)
void	meet(ProjectionElemList theProjectionElemList)
void	meet(Reduced theReduced)
void	meet(Slice theSlice)
void	meet(StatementPattern theStatementPattern)
String	render(ParsedQuery theQuery) Render the ParsedQuery as a query string
abstract String	render(TupleExpr theExpr) Render the TupleExpr as a query or query fragment depending on what kind of TupleExpr it is
protected abstract String	renderValueExpr(ValueExpr theExpr) Render the given ValueExpr
void	reset() Reset the state of the renderer
static String	scrubVarName(String theName) Scrub any illegal characters out of the variable name
StatementPattern	toStatementPattern(ProjectionElemList theList) Turn a ProjectionElemList for a construct query projection (three elements aliased as 'subject', 'predicate' and 'object' in that order) into a StatementPattern.

Methods inherited from class org.eclipse.rdf4j.query.algebra.helpers.AbstractQueryModelVisitor

meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meet, meetBinaryTupleOperator, meetBinaryValueOperator, meetCompareSubQueryValueOperator, meetNAryValueOperator, meetNode, meetOther, meetSubQueryValueOperator, meetUnaryTupleOperator, meetUnaryValueOperator, meetUpdateExpr

Methods inherited from class java.lang.Object

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

Field Detail

mExtensions

protected Map<String,ValueExpr> mExtensions

A map of the extensions specified in the query.

mProjection

protected List<ProjectionElemList> mProjection

The list of elements include in the projection of the query

mOrdering

protected List<OrderElem> mOrdering

The elements specified in the order by clause of the query

mDistinct

protected boolean mDistinct

Whether or not the query is distinct

mReduced

protected boolean mReduced

Whether or not the query is reduced

mLimit

protected long mLimit

The limit of results for the query, or -1 for no limit

mOffset

protected long mOffset

The query offset, or -1 for no offset

Constructor Detail

BaseTupleExprRenderer

public BaseTupleExprRenderer()

Method Detail

reset

public void reset()

Reset the state of the renderer

getExtensions

public Map<String,ValueExpr> getExtensions()

getProjection

public List<ProjectionElemList> getProjection()

getOrdering

public List<OrderElem> getOrdering()

isDistinct

public boolean isDistinct()

isReduced

public boolean isReduced()

getLimit

public long getLimit()

getOffset

public long getOffset()

render

public String render(ParsedQuery theQuery)
              throws Exception

Render the ParsedQuery as a query string

Parameters:

theQuery - the parsed query to render

Returns:

the query object rendered in the serql syntax

Throws:

Exception - if there is an error while rendering

render

public abstract String render(TupleExpr theExpr)
                       throws Exception

Render the TupleExpr as a query or query fragment depending on what kind of TupleExpr it is

Parameters:

theExpr - the expression to render

Returns:

the TupleExpr rendered in the serql syntax

Throws:

Exception - if there is an error while rendering

renderValueExpr

protected abstract String renderValueExpr(ValueExpr theExpr)
                                   throws Exception

Render the given ValueExpr

Parameters:

theExpr - the expr to render

Returns:

the rendered expression

Throws:

Exception - if there is an error while rendering

toStatementPattern

public StatementPattern toStatementPattern(ProjectionElemList theList)
                                    throws Exception

Turn a ProjectionElemList for a construct query projection (three elements aliased as 'subject', 'predicate' and 'object' in that order) into a StatementPattern.

Parameters:

theList - the elem list to render

Returns:

the elem list for a construct projection as a statement pattern

Throws:

Exception - if there is an exception while rendering

scrubVarName

public static String scrubVarName(String theName)

Scrub any illegal characters out of the variable name

Parameters:

theName - the potential variable name

Returns:

the name scrubbed of any illegal characters

isSelect

protected boolean isSelect()

Returns whether or not the results of scanning the query model indicates that this represents a select query

Returns:

true if its a select query, false if its a construct query

isSPOElemList

public static boolean isSPOElemList(ProjectionElemList theList)

Return whether or not this projection looks like an spo binding for a construct query

Parameters:

theList - the projection element list to inspect

Returns:

true if it has the format of a spo construct projection element, false otherwise

meet

public void meet(StatementPattern theStatementPattern)
          throws Exception

Specified by:

meet in interface QueryModelVisitor<Exception>

Overrides:

meet in class AbstractQueryModelVisitor<Exception>

Throws:

Exception

meet

public void meet(Slice theSlice)
          throws Exception

Specified by:

meet in interface QueryModelVisitor<Exception>

Overrides:

meet in class AbstractQueryModelVisitor<Exception>

Throws:

Exception

meet

public void meet(ExtensionElem theExtensionElem)
          throws Exception

Specified by:

meet in interface QueryModelVisitor<Exception>

Overrides:

meet in class AbstractQueryModelVisitor<Exception>

Throws:

Exception

meet

public void meet(ProjectionElemList theProjectionElemList)
          throws Exception

Specified by:

meet in interface QueryModelVisitor<Exception>

Overrides:

meet in class AbstractQueryModelVisitor<Exception>

Throws:

Exception

meet

public void meet(OrderElem theOrderElem)
          throws Exception

Specified by:

meet in interface QueryModelVisitor<Exception>

Overrides:

meet in class AbstractQueryModelVisitor<Exception>

Throws:

Exception

meet

public void meet(Distinct theDistinct)
          throws Exception

Specified by:

meet in interface QueryModelVisitor<Exception>

Overrides:

meet in class AbstractQueryModelVisitor<Exception>

Throws:

Exception

meet

public void meet(Reduced theReduced)
          throws Exception

Specified by:

meet in interface QueryModelVisitor<Exception>

Overrides:

meet in class AbstractQueryModelVisitor<Exception>

Throws:

Exception