com.singularsys.jep.standard
Class FastEvaluator

java.lang.Object
  com.singularsys.jep.standard.FastEvaluator

All Implemented Interfaces:

Evaluator, JepComponent, ParserVisitor, java.io.Serializable

public class FastEvaluator
extends java.lang.Object
implements Evaluator, ParserVisitor

See Also:

Serialized Form

Constructor Summary

FastEvaluator()

Method Summary

java.lang.Object	eval(Node node) Evaluates a sub expression.
java.lang.Object	evaluate(Node node) Evaluates a node and returns and object with the value of the node.
JepComponent	getLightWeightInstance() Gets a light-weight instance suitable for using in multiple threads.
void	init(Jep jep) Initialize the component.
boolean	isTrapInfinity()
boolean	isTrapNaN()
boolean	isTrapNullValues() Whether null values for variables are trapped.
protected java.lang.Object	nodeAccept(Node node)
void	setTrapInfinity(boolean trapInfinity)
void	setTrapNaN(boolean trapNaN)
void	setTrapNullValues(boolean trapNullValues) Sets whether null values for variables are trapped.
java.lang.Object	visit(ASTConstant node, java.lang.Object data)
java.lang.Object	visit(ASTFunNode node, java.lang.Object data)
java.lang.Object	visit(ASTOpNode node, java.lang.Object data)
java.lang.Object	visit(ASTVarNode node, java.lang.Object data)
java.lang.Object	visitConstant(Node node)
protected java.lang.Object	visitFun(Node node) Visits a function/operator node.
java.lang.Object	visitVar(Node node)

Methods inherited from class java.lang.Object

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

Constructor Detail

FastEvaluator

public FastEvaluator()

Method Detail

init

public void init(Jep jep)

Description copied from interface: JepComponent

Initialize the component. This methods is called whenever a component is added to Jep. Hence it allows components to keep track of the other components they may rely on.

Specified by:

init in interface JepComponent

Parameters:

jep - the current Jep instance

eval

public java.lang.Object eval(Node node)
                      throws EvaluationException

Description copied from interface: Evaluator

Evaluates a sub expression.

Specified by:

eval in interface Evaluator

Throws:

EvaluationException - if errors occur during evaluation;

evaluate

public java.lang.Object evaluate(Node node)
                          throws EvaluationException

Description copied from interface: Evaluator

Evaluates a node and returns and object with the value of the node.

Specified by:

evaluate in interface Evaluator

Throws:

EvaluationException - if errors occur during evaluation;

nodeAccept

protected java.lang.Object nodeAccept(Node node)
                               throws EvaluationException

Throws:

EvaluationException

visit

public java.lang.Object visit(ASTConstant node,
                              java.lang.Object data)
                       throws EvaluationException

Specified by:

visit in interface ParserVisitor

Throws:

EvaluationException

visitConstant

public java.lang.Object visitConstant(Node node)
                               throws EvaluationException

Throws:

EvaluationException

visit

public java.lang.Object visit(ASTVarNode node,
                              java.lang.Object data)
                       throws EvaluationException

Specified by:

visit in interface ParserVisitor

Throws:

EvaluationException

visitVar

public java.lang.Object visitVar(Node node)
                          throws EvaluationException

Throws:

EvaluationException

visit

public java.lang.Object visit(ASTFunNode node,
                              java.lang.Object data)
                       throws EvaluationException

Specified by:

visit in interface ParserVisitor

Throws:

EvaluationException

visit

public java.lang.Object visit(ASTOpNode node,
                              java.lang.Object data)
                       throws EvaluationException

Specified by:

visit in interface ParserVisitor

Throws:

EvaluationException

visitFun

protected java.lang.Object visitFun(Node node)
                             throws EvaluationException

Visits a function/operator node. This is the most visited method for most expression evaluations. Keeping it fast is important.

Parameters:

node -

Throws:

EvaluationException

isTrapNullValues

public boolean isTrapNullValues()

Whether null values for variables are trapped.

Returns:

the status if the trap null values flag.

setTrapNullValues

public void setTrapNullValues(boolean trapNullValues)

Sets whether null values for variables are trapped. If set (the default) then an EvaluationException is thrown for null values of variables. If not set then null values are passed to PostfixMathCommands who will need to test for null values.

Parameters:

trapNullValues -

isTrapNaN

public boolean isTrapNaN()

setTrapNaN

public void setTrapNaN(boolean trapNaN)

isTrapInfinity

public boolean isTrapInfinity()

setTrapInfinity

public void setTrapInfinity(boolean trapInfinity)

getLightWeightInstance

public JepComponent getLightWeightInstance()

Description copied from interface: JepComponent

Gets a light-weight instance suitable for using in multiple threads.

Specified by:

getLightWeightInstance in interface JepComponent

Returns:

an new FastEvaluator