FormulaEvaluatorUtil.FunctionWithListAsArgumentHelper (org.faktorips.runtime 21.6.0-SNAPSHOT API)

java.lang.Object
- org.faktorips.runtime.formula.FormulaEvaluatorUtil.FunctionWithListAsArgumentHelper<E>

Enclosing class:

FormulaEvaluatorUtil
```
public abstract static class FormulaEvaluatorUtil.FunctionWithListAsArgumentHelper<E>
extends java.lang.Object
```
Base class for functions working on list arguments. Subclasses define the function by overwriting getPreliminaryResult(Object, Object) and getFallBackValue().

Author:

HBaagil

Constructor Summary

Constructors
Constructor Description

FunctionWithListAsArgumentHelper()

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method	Description
`abstract E`	`getFallBackValue()`	Returns the value this function defaults to if an empty list or null is given as an argument.
`abstract E`	`getPreliminaryResult(E currentResult, E nextValue)`	Calculates a preliminary result based on the current result and the next value in the list.
`E`	`getResult(java.util.List<E> listOfValues)`	Returns the result of this function given a list of values.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - FunctionWithListAsArgumentHelper
```
public FunctionWithListAsArgumentHelper()
```
- Method Detail
  - getResult
```
public E getResult(java.util.List<E> listOfValues)
```
    Returns the result of this function given a list of values.
    
    Parameters:
    
    listOfValues - A List of values.
  - getFallBackValue
```
public abstract E getFallBackValue()
```
    Returns the value this function defaults to if an empty list or null is given as an argument. E.g. for the function sum, the fall back value is 0.
  - getPreliminaryResult
```
public abstract E getPreliminaryResult(E currentResult,
                                       E nextValue)
```
    Calculates a preliminary result based on the current result and the next value in the list.
    
    Parameters:
    
    currentResult - The current result calculated up to this point.
    
    nextValue - The value to be considered next.
    
    Returns:
    
    The result of the operation defined by subclasses.