Package com.ezylang.evalex.functions

Interface FunctionIfc

All Known Implementing Classes:

AbsFunction, AbstractFunction, AcosFunction, AcosHFunction, AcosRFunction, AcotFunction, AcotHFunction, AcotRFunction, AsinFunction, AsinHFunction, AsinRFunction, Atan2Function, Atan2RFunction, AtanFunction, AtanHFunction, AtanRFunction, CeilingFunction, CoalesceFunction, CosFunction, CosHFunction, CosRFunction, CotFunction, CotHFunction, CotRFunction, CscFunction, CscHFunction, CscRFunction, DateTimeFormatFunction, DateTimeNewFunction, DateTimeParseFunction, DateTimeToEpochFunction, DegFunction, DurationFromMillisFunction, DurationNewFunction, DurationParseFunction, DurationToMillisFunction, FactFunction, FloorFunction, IfFunction, Log10Function, LogFunction, MaxFunction, MinFunction, NotFunction, RadFunction, RandomFunction, RoundFunction, SecFunction, SecHFunction, SecRFunction, SinFunction, SinHFunction, SinRFunction, SqrtFunction, StringContains, StringLowerFunction, StringUpperFunction, SumFunction, TanFunction, TanHFunction, TanRFunction

public interface FunctionIfc

Interface that is required for all functions in a function dictionary for evaluation of expressions.

Method Summary

Modifier and Type	Method	Description
EvaluationValue	evaluate(Expression expression, Token functionToken, EvaluationValue... parameterValues)	Performs the function logic and returns an evaluation result.
java.util.List<FunctionParameterDefinition>	getFunctionParameterDefinitions()	Returns the list of parameter definitions.
boolean	hasVarArgs()	Checks whether the function has a variable number of arguments parameter.
default boolean	isParameterLazy(int parameterIndex)	Checks if the parameter is a lazy parameter.
void	validatePreEvaluation(Token token, EvaluationValue... parameterValues)	Validates the evaluation parameters, called before the actual evaluation.

Method Detail

getFunctionParameterDefinitions

java.util.List<FunctionParameterDefinition> getFunctionParameterDefinitions()

Returns the list of parameter definitions. Is never empty or null.

Returns:

The parameter definition list.

evaluate

EvaluationValue evaluate(Expression expression,
                         Token functionToken,
                         EvaluationValue... parameterValues)
                  throws EvaluationException

Performs the function logic and returns an evaluation result.

Parameters:

expression - The expression, where this function is executed. Can be used to access the expression configuration.

functionToken - The function token from the parsed expression.

parameterValues - The parameter values.

Returns:

The evaluation result in form of a EvaluationValue.

Throws:

EvaluationException - In case there were problems during evaluation.

validatePreEvaluation

void validatePreEvaluation(Token token,
                           EvaluationValue... parameterValues)
                    throws EvaluationException

Validates the evaluation parameters, called before the actual evaluation.

Parameters:

token - The function token.

parameterValues - The parameter values

Throws:

EvaluationException - in case of any validation error

hasVarArgs

boolean hasVarArgs()

Checks whether the function has a variable number of arguments parameter.

Returns:

true or false:

isParameterLazy

default boolean isParameterLazy(int parameterIndex)

Checks if the parameter is a lazy parameter.

Parameters:

parameterIndex - The parameter index, starts at 0 for the first parameter. If the index is bigger than the list of parameter definitions, the last parameter definition will be checked.

Returns:

true if the specified parameter is defined as lazy.