com.hp.hpl.jena.sparql.expr

Class ExprNode

java.lang.Object

com.hp.hpl.jena.sparql.expr.ExprNode

All Implemented Interfaces:

Expr

Direct Known Subclasses:

ExprAggregator, ExprFunction, ExprVar, NodeValue

public abstract class ExprNode
extends Object
implements Expr

A node that is a constraint expression that can be evaluated An Expr is already a Constraint - ExprNode is the base implementation of all Expr classes that provides the Constraint machinary.

Field Summary

Fields inherited from interface com.hp.hpl.jena.sparql.expr.Expr

CMP_EQUAL, CMP_GREATER, CMP_INDETERMINATE, CMP_LESS, CMP_UNEQUAL

Constructor Summary

Constructors

Constructor and Description
ExprNode()

Method Summary

Methods

Modifier and Type	Method and Description
abstract Expr	applyNodeTransform(NodeTransform transform) Rewrite, applying a node->node transformation
Var	asVar() Convert to a Var variable.
abstract Expr	copySubstitute(Binding binding) Deep copy with substitution
Expr	deepCopy() Deep copy
abstract boolean	equals(Object other)
abstract NodeValue	eval(Binding binding, FunctionEnv env) Evaluate this expression against the binding
NodeValue	getConstant() NodeValue constant (returns null if not a constant)
Expr	getExpr()
ExprVar	getExprVar() Variable (or null)
ExprFunction	getFunction() Get the function (returns null if not a function)
Op	getGraphPattern()
String	getVarName() Variable name (returns null if not a variable)
Set<String>	getVarNamesMentioned()
Set<Var>	getVarsMentioned() Variables used by this expression - excludes variables scoped to (NOT)EXISTS
abstract int	hashCode()
boolean	isConstant() Answer whether this is a constant expression - false includes "don't know" No constant folding so "false" from an expression that evaluates to a constant
boolean	isExpr()
boolean	isFunction() Answer wether this is a function.
boolean	isGraphPattern()
boolean	isSatisfied(Binding binding, FunctionEnv funcEnv) Test whether a Constraint is satisfied, given a set of bindings Includes error propagtion and Effective Boolean Value rules.
boolean	isVariable() Answer whether this is a variable (in which case getVarName and getNodeVar can be called)
String	toString()
void	varNamesMentioned(Collection<String> acc)
void	varsMentioned(Collection<Var> acc) Variables used by this expression - excludes variables scoped to (NOT)EXISTS

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface com.hp.hpl.jena.sparql.expr.Expr

visit

Constructor Detail

ExprNode

public ExprNode()

Method Detail

isSatisfied

public boolean isSatisfied(Binding binding,
                  FunctionEnv funcEnv)

Description copied from interface: Expr

Test whether a Constraint is satisfied, given a set of bindings Includes error propagtion and Effective Boolean Value rules.

Specified by:

isSatisfied in interface Expr

Parameters:

binding - The bindings

funcEnv - FunctionEnv

Returns:

true or false

isExpr

public boolean isExpr()

getExpr

public final Expr getExpr()

eval

public abstract NodeValue eval(Binding binding,
             FunctionEnv env)

Description copied from interface: Expr

Evaluate this expression against the binding

Specified by:

eval in interface Expr

getVarsMentioned

public Set<Var> getVarsMentioned()

Description copied from interface: Expr

Variables used by this expression - excludes variables scoped to (NOT)EXISTS

Specified by:

getVarsMentioned in interface Expr

varsMentioned

public void varsMentioned(Collection<Var> acc)

Description copied from interface: Expr

Variables used by this expression - excludes variables scoped to (NOT)EXISTS

Specified by:

varsMentioned in interface Expr

getVarNamesMentioned

public Set<String> getVarNamesMentioned()

varNamesMentioned

public void varNamesMentioned(Collection<String> acc)

hashCode

public abstract int hashCode()

Overrides:

hashCode in class Object

equals

public abstract boolean equals(Object other)

Overrides:

equals in class Object

deepCopy

public final Expr deepCopy()

Description copied from interface: Expr

Deep copy

Specified by:

deepCopy in interface Expr

copySubstitute

public abstract Expr copySubstitute(Binding binding)

Description copied from interface: Expr

Deep copy with substitution

Specified by:

copySubstitute in interface Expr

applyNodeTransform

public abstract Expr applyNodeTransform(NodeTransform transform)

Description copied from interface: Expr

Rewrite, applying a node->node transformation

Specified by:

applyNodeTransform in interface Expr

isVariable

public boolean isVariable()

Description copied from interface: Expr

Answer whether this is a variable (in which case getVarName and getNodeVar can be called)

Specified by:

isVariable in interface Expr

getVarName

public String getVarName()

Description copied from interface: Expr

Variable name (returns null if not a variable)

Specified by:

getVarName in interface Expr

getExprVar

public ExprVar getExprVar()

Description copied from interface: Expr

Variable (or null)

Specified by:

getExprVar in interface Expr

asVar

public Var asVar()

Description copied from interface: Expr

Convert to a Var variable.

Specified by:

asVar in interface Expr

isConstant

public boolean isConstant()

Description copied from interface: Expr

Answer whether this is a constant expression - false includes "don't know" No constant folding so "false" from an expression that evaluates to a constant

Specified by:

isConstant in interface Expr

getConstant

public NodeValue getConstant()

Description copied from interface: Expr

NodeValue constant (returns null if not a constant)

Specified by:

getConstant in interface Expr

isFunction

public boolean isFunction()

Description copied from interface: Expr

Answer wether this is a function.

Specified by:

isFunction in interface Expr

getFunction

public ExprFunction getFunction()

Description copied from interface: Expr

Get the function (returns null if not a function)

Specified by:

getFunction in interface Expr

isGraphPattern

public boolean isGraphPattern()

getGraphPattern

public Op getGraphPattern()

toString

public String toString()

Overrides:

toString in class Object