Package org.apache.felix.gogo.runtime

Class Expression.Function

java.lang.Object

org.apache.felix.gogo.runtime.Expression.Function

All Implemented Interfaces:

Expression.Token

Enclosing class:

Expression

public abstract class Expression.Function
extends Object
implements Expression.Token

Abstract definition of a supported expression function. A function is defined by a name, the number of parameters and the actual processing implementation.

Field Summary

Fields

Modifier and Type	Field	Description
private String	name	Name of this function.
private int	numParams	Number of parameters expected for this function.

Constructor Summary

Constructors

Constructor	Description
Function(String name, int numParams)	Creates a new function with given name and parameter count.

Method Summary

Modifier and Type	Method	Description
abstract BigDecimal	eval(List<BigDecimal> parameters)	Implementation for this function.
BigDecimal	eval(Map<String,Object> variables, List<Object> parameters)
String	getName()
int	getNumParams()
String	toString()

Methods inherited from class java.lang.Object

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

Field Details

name

private String name

Name of this function.

numParams

private int numParams

Number of parameters expected for this function.

Constructor Details

Function

public Function(String name,
 int numParams)

Creates a new function with given name and parameter count.

Parameters:

name - The name of the function.

numParams - The number of parameters for this function.

Method Details

getName

public String getName()

getNumParams

public int getNumParams()

eval

public BigDecimal eval(Map<String,Object> variables,
 List<Object> parameters)

eval

public abstract BigDecimal eval(List<BigDecimal> parameters)

Implementation for this function.

Parameters:

parameters - Parameters will be passed by the expression evaluator as a List of BigDecimal values.

Returns:

The function must return a new BigDecimal value as a computing result.

toString

public String toString()

Overrides:

toString in class Object