Package com.singularsys.jep.misc.functions

# Class CaseNonLazy

java.lang.Object
com.singularsys.jep.functions.PostfixMathCommand
com.singularsys.jep.functions.NaryFunction
com.singularsys.jep.misc.functions.CaseNonLazy

All Implemented Interfaces:
  `PostfixMathCommandI`, `Serializable`

public class CaseNonLazy extends NaryFunction
A case statement. The argument first argument is evaluated and then checked against the 2nd, 4th, 6th argument if the two are equal then the 3rd, 5th, 7th argument is returned. If no arguments match then the last argument is returned (if the number of args is even) for example `case("c","a",5,"b",6,"c",7,8)` will return 7.

This is the non-lazy evaluation version, it will evaluate all arguments. Use `Case` for a lazy version which only evaluates arguments when needed.

Since:
  Jep 4.1
Author:
  Richard Morris
See Also:
  - `Switch`
  - Serialized Form

- ## Nested Class Summary

  Nested Classes
  Modifier and Type
  Class
  Description
  `static enum`
  `CaseNonLazy.NullBehaviour`
  Action to take if first argument is null.

- ## Field Summary

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

  `curNumberOfParameters, description, name, NaN, numberOfParameters`

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `CaseNonLazy()`
  Standard constructor with no default value and errors if nulls are found.
  `CaseNonLazy(CaseNonLazy.NullBehaviour nullBehaviour)`
  Constructor with defined behaviour for null.
  `CaseNonLazy(Object defaultVal)`
  A case statement with a predefined default value and errors if nulls are found.
  `CaseNonLazy(Object defaultVal, CaseNonLazy.NullBehaviour nullBehaviour)`
  Case statement with given default value and defined null behaviour.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `boolean`
  `checkNumberOfParameters(int n)`
  Must have at least 3 parameters.
  `Object`
  `eval(Object[] vals)`
  Evaluate with a know set of arguments.
  `Object`
  `getDefaultVal()`
  The default value, only meaningful if isHasDefault() is true.
  `CaseNonLazy.NullBehaviour`
  `getNullBehaviour()`
  Behaviour when passed zero arguments.
  `boolean`
  `isHasDefault()`
  Whether a default value is set

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

  `run`

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

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

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

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

- ## Constructor Details

  - ### CaseNonLazy

    public CaseNonLazy()
    Standard constructor with no default value and errors if nulls are found.

  - ### CaseNonLazy

    public CaseNonLazy(CaseNonLazy.NullBehaviour nullBehaviour)
    Constructor with defined behaviour for null.
    Parameters:
      `nullBehaviour` - action to take if first argument is null
    Since:
      Jep 3.5

  - ### CaseNonLazy

    public CaseNonLazy(Object defaultVal)
    A case statement with a predefined default value and errors if nulls are found.
    Parameters:
      `defaultVal` - The default value to return when no cases match
    Since:
      Jep 3.5

  - ### CaseNonLazy

    public CaseNonLazy(Object defaultVal, CaseNonLazy.NullBehaviour nullBehaviour)
    Case statement with given default value and defined null behaviour.
    Parameters:
      `defaultVal` - The default value to return when no cases match
      `nullBehaviour` - action to take if first argument is null
    Since:
      Jep 3.5

- ## Method Details

  - ### isHasDefault

    public boolean isHasDefault()
    Whether a default value is set
    Returns:
      true if a default value is set
    Since:
      Jep 3.5

  - ### getDefaultVal

    public Object getDefaultVal()
    The default value, only meaningful if isHasDefault() is true.
    Returns:
      the default value used.
    Since:
      Jep 3.5

  - ### getNullBehaviour

    public CaseNonLazy.NullBehaviour getNullBehaviour()
    Behaviour when passed zero arguments.
    Returns:
      code indicating behaviour type
    Since:
      Jep 3.5

  - ### checkNumberOfParameters

    public boolean checkNumberOfParameters(int n)
    Must have at least 3 parameters.
    Specified by:
      `checkNumberOfParameters` in interface `PostfixMathCommandI`
    Overrides:
      `checkNumberOfParameters` in class `PostfixMathCommand`
    Parameters:
      `n` - number of parameters function will be called with.
    Returns:
      false if an illegal number of parameters is supplied, true otherwise.

  - ### eval

    public Object eval(Object[] vals) throws EvaluationException
    Evaluate with a know set of arguments.
    Specified by:
      `eval` in class `NaryFunction`
    Parameters:
      `vals` - an array of arguments
    Returns:
      the result
    Throws:
      `EvaluationException` - if the calculation cannot be performed