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

# Class NullWrappedLazyLogical

java.lang.Object
com.singularsys.jep.functions.PostfixMathCommand
com.singularsys.jep.misc.nullwrapper.functions.NullWrappedLazyLogical

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

public class NullWrappedLazyLogical extends PostfixMathCommand implements CallbackEvaluationI, NullWrappedFunctionI
Null wrapped versions of the LazyLogical functions. In version 3.5 the convention has been changed to behave like the MySQL logical operators.

OR truth table
A OR B | True | False | null
--- | --- | --- | ---
True | True | True | True
False | True | False | null
null | True | null | null

AND truth table
A AND B | True | False | null
--- | --- | --- | ---
True | True | False | null
False | False | False | False
null | null | False | null

NOT truth table
A | NOT A
--- | ---
True | False
False | True
null | null

Since:
  3.4
Version:
  3.5
Author:
  Richard Morris
See Also:
  - `LazyLogical`
  - Serialized Form

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `protected boolean`
  `allowNumbers`
  `static final int`
  `AND`
  `protected final int`
  `id`
  Represents which logical operator this is.
  `static final int`
  `OR`

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

  `curNumberOfParameters, description, name, NaN, numberOfParameters`

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `NullWrappedLazyLogical(int id_in)`
  Standard constructor, non-zero Numbers will be treated as true and zero Numbers as false.
  `NullWrappedLazyLogical(int id_in, boolean disallowNumbers)`
  Constructor which restricts type of arguments.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `Object`
  `evaluate(Node node, Evaluator pv)`
  Performs some special evaluation on the node.
  `String`
  `getDescription()`
  Return a description of the function from the properties file.
  `PostfixMathCommandI`
  `getRoot()`
  Get to function which this function wraps.

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

  `asArray, asBool, asDouble, asInt, asLong, asStrictInt, asString, asType, checkNumberOfParameters, 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`

- ## Field Details

  - ### AND

    public static final int AND
    See Also:
      - Constant Field Values

  - ### OR

    public static final int OR
    See Also:
      - Constant Field Values

  - ### id

    protected final int id
    Represents which logical operator this is.

  - ### allowNumbers

    protected boolean allowNumbers

- ## Constructor Details

  - ### NullWrappedLazyLogical

    public NullWrappedLazyLogical(int id_in)
    Standard constructor, non-zero Numbers will be treated as true and zero Numbers as false.
    Parameters:
      `id_in` - either of the constants `AND` or `OR`

  - ### NullWrappedLazyLogical

    public NullWrappedLazyLogical(int id_in, boolean disallowNumbers)
    Constructor which restricts type of arguments.
    Parameters:
      `id_in` -
      `disallowNumbers` - if true Number arguments will raise exceptions, otherwise as the Standard constructor.

- ## 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`
    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`

  - ### getDescription

    public String getDescription()
    Description copied from class: `PostfixMathCommand`
    Return a description of the function from the properties file. The property name is the class name followed by ".description". The property is found using the `JepMessages` class, which can be configured to add additional properties files. If `PostfixMathCommand.setDescription(String)` has been called, return the description set by that method instead.
    Specified by:
      `getDescription` in interface `PostfixMathCommandI`
    Overrides:
      `getDescription` in class `PostfixMathCommand`
    Returns:
      the description of the function