com.hp.hpl.jena.graph.query
Class Expression.BoolConstant

java.lang.Object
  extended bycom.hp.hpl.jena.graph.query.Expression.Base
      extended bycom.hp.hpl.jena.graph.query.Expression.BoolConstant
All Implemented Interfaces:
Expression, Valuator
Enclosing class:
Expression

public static class Expression.BoolConstant
extends Expression.Base
implements Expression, Valuator

Base class used to implement TRUE and FALSE.


Nested Class Summary
 
Nested classes inherited from class com.hp.hpl.jena.graph.query.Expression
Expression.Application, Expression.Base, Expression.BoolConstant, Expression.Literal, Expression.Util, Expression.Valof, Expression.Variable
 
Field Summary
 
Fields inherited from interface com.hp.hpl.jena.graph.query.Expression
FALSE, TRUE
 
Constructor Summary
Expression.BoolConstant(boolean value)
           
 
Method Summary
 boolean evalBool(IndexValues vv)
           
 boolean evalBool(VariableValues vv)
          Answer true iff the Expression evaluates to true given the variable bindings.
 java.lang.Object getValue()
          If this Expression is a literal, answer the value of that literal.
 boolean isLiteral()
          Answer true iff this Expression represents a literal [Java object] value.
 Valuator prepare(VariableIndexes vi)
          Answer a Valuator which does the same evaluation as this Expression when supplied with a mapping from variable indexes to their values.
 
Methods inherited from class com.hp.hpl.jena.graph.query.Expression.Base
argCount, getArg, getFun, getName, isApply, isVariable
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface com.hp.hpl.jena.graph.query.Expression
argCount, getArg, getFun, getName, isApply, isVariable
 

Constructor Detail

Expression.BoolConstant

public Expression.BoolConstant(boolean value)
Method Detail

isLiteral

public boolean isLiteral()
Description copied from interface: Expression
Answer true iff this Expression represents a literal [Java object] value.

Specified by:
isLiteral in interface Expression
Overrides:
isLiteral in class Expression.Base

getValue

public java.lang.Object getValue()
Description copied from interface: Expression
If this Expression is a literal, answer the value of that literal. Otherwise the behaviour is unspecified.

Specified by:
getValue in interface Expression
Overrides:
getValue in class Expression.Base

prepare

public Valuator prepare(VariableIndexes vi)
Description copied from interface: Expression
Answer a Valuator which does the same evaluation as this Expression when supplied with a mapping from variable indexes to their values. The composition of the variable->index map vi and the index->value map given to the valuator is equivalent to the VariableValues map that would be supplied to evalBool.

Specified by:
prepare in interface Expression
Overrides:
prepare in class Expression.Base

evalBool

public boolean evalBool(VariableValues vv)
Description copied from interface: Expression
Answer true iff the Expression evaluates to true given the variable bindings.

Specified by:
evalBool in interface Expression
Parameters:
vv - the mapping from variable[ name]s to their values

evalBool

public boolean evalBool(IndexValues vv)
Specified by:
evalBool in interface Valuator


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