Package com.singularsys.jep.misc.nullwrapper.functions

# Class NullWrappedIf

java.lang.Object
com.singularsys.jep.functions.PostfixMathCommand
com.singularsys.jep.functions.If
com.singularsys.jep.misc.nullwrapper.functions.NullWrappedIf

All Implemented Interfaces:
  `CallbackEvaluationI`, `NullWrappedFunctionI`, `PostfixMathCommandI`, `Serializable`

public class NullWrappedIf extends If implements NullWrappedFunctionI
NullWrapped version of the if function. If the first argument is null then null is returned otherwise results are the same as the standard `if` function.

Since:
  3.4
Author:
  Richard Morris
See Also:
  - `If`
  - Serialized Form

- ## Field Summary

  ### Fields inherited from class com.singularsys.jep.functions.If

  `falseValue`

  ### Fields inherited from class com.singularsys.jep.functions.PostfixMathCommand

  `curNumberOfParameters, description, name, NaN, numberOfParameters`

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `NullWrappedIf()`
  `NullWrappedIf(Object falseValue)`

- ## Method Summary

  Modifier and Type
  Method
  Description
  `Object`
  `evaluate(Node node, Evaluator pv)`
  Performs some special evaluation on the node.
  `PostfixMathCommandI`
  `getRoot()`
  Get to function which this function wraps.

  ### Methods inherited from class com.singularsys.jep.functions.If

  `checkNumberOfParameters, getFalseValue`

  ### Methods inherited from class com.singularsys.jep.functions.PostfixMathCommand

  `asArray, asBool, asDouble, asInt, asLong, asStrictInt, asString, asType, getDescription, getDescription, getDescriptionWithType, getName, getNumberOfParameters, run, setCurNumberOfParameters, setDescription, setName, toString, toString`

  ### Methods inherited from class java.lang.Object

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

- ## Constructor Details

  - ### NullWrappedIf

    public NullWrappedIf()

  - ### NullWrappedIf

    public NullWrappedIf(Object falseValue)
    Parameters:
      `falseValue` -

- ## Method Details

  - ### getRoot

    public PostfixMathCommandI getRoot()
    Description copied from interface: `NullWrappedFunctionI`
    Get to function which this function wraps.
    Specified by:
      `getRoot` in interface `NullWrappedFunctionI`
    Returns:
      the root function, may be "this".

  - ### evaluate

    public Object evaluate(Node node, Evaluator pv) throws EvaluationException
    Description copied from interface: `CallbackEvaluationI`
    Performs some special evaluation on the node. This method has the responsibility for evaluating the children of the node, and it should generally call

         pv.eval(node.jjtGetChild(i))

    for each child. The SymbolTable is not passed as an argument. This is because it is better practice to get and set variable values by using node.getVar().setValue() rather that through the SymbolTable with requires a hashtable lookup.
    Specified by:
      `evaluate` in interface `CallbackEvaluationI`
    Overrides:
      `evaluate` in class `If`
    Parameters:
      `node` - The current node
      `pv` - The visitor, can be used evaluate the children
    Returns:
      the value after evaluation. This value will be passed to other functions higher up the node tree. The value can be any type including Double or Vector<Object>
    Throws:
      `EvaluationException` - if the calculation cannot be performed
    See Also:
      - `Evaluator`