Package org.djutils.eval

Class F0

java.lang.Object

org.djutils.eval.F0

All Implemented Interfaces:

Identifiable, Function

class F0
extends Object
implements Function

F0.java. Minimal implementation of zero-argument Function with description.

Copyright (c) 2023-2025 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved. See for project information https://djutils.org. The DJUTILS project is distributed under a three-clause BSD-style license, which can be found at https://djutils.org/docs/license.html.

Author:

Peter Knoppers

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
(package private) static interface	F0.ZeroArgumentFunction	Interface for zero argument functions.

Field Summary

Fields

Modifier and Type	Field	Description
(package private) final F0.ZeroArgumentFunction	f0	The zero argument function.
(package private) final String	id	Id of the function.
(package private) final MetaData	metaData	Type of the parameters of this function (also contains name and description).
(package private) final Class<?>	resultClass	Type of the result of this function.

Constructor Summary

Constructors

Constructor	Description
F0(String id, Class<?> resultClass, MetaData metaData, F0.ZeroArgumentFunction f0)	Construct a new zero argument function.
F0(String id, Object constantResult, MetaData metaData)	Construct a new zero-argument function with constant result.

Method Summary

Modifier and Type	Method	Description
Object	function(Object[] arguments)	The function itself.
String	getId()
MetaData	getMetaData()	Specifies the types of the arguments expected by the function.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.djutils.eval.Function

getDescription, getName

Field Details

id

final String id

Id of the function.

metaData

final MetaData metaData

Type of the parameters of this function (also contains name and description).

resultClass

final Class<?> resultClass

Type of the result of this function.

f0

final F0.ZeroArgumentFunction f0

The zero argument function.

Constructor Details

F0

F0(String id,
 Class<?> resultClass,
 MetaData metaData,
 F0.ZeroArgumentFunction f0)

Construct a new zero argument function.

Parameters:

id - name of the function as it must be written in expressions

resultClass - the type of the result of the function

metaData - meta data of the function

f0 - zero argument function

F0

F0(String id,
 Object constantResult,
 MetaData metaData)

Construct a new zero-argument function with constant result.

Parameters:

id - name of the function as it must be written in expressions

constantResult - the result of the zero argument function

metaData - meta data of the function

Method Details

getId

public String getId()

Specified by:

getId in interface Identifiable

getMetaData

public MetaData getMetaData()

Description copied from interface: Function

Specifies the types of the arguments expected by the function.

Specified by:

getMetaData in interface Function

Returns:

specification of the arguments expected by the function

function

public Object function(Object[] arguments)
                throws RuntimeException

Description copied from interface: Function

The function itself.

Specified by:

function in interface Function

Parameters:

arguments - the arguments of the function

Returns:

the result of the function (must currently be either some type of DoubleScalar or Boolean).

Throws:

RuntimeException - thrown when the function is unable to produce a result