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

Class NullWrappedPfmc

java.lang.Object

com.singularsys.jep.functions.PostfixMathCommand

com.singularsys.jep.misc.nullwrapper.functions.NullWrappedPfmc

All Implemented Interfaces:

NullWrappedFunctionI, PostfixMathCommandI, Serializable

public class NullWrappedPfmc
extends PostfixMathCommand
implements NullWrappedFunctionI

Wrap a general PostfixMathCommand so that if any argument is null the function will return null.

Since:

3.4

Author:

Richard Morris

See Also:

• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
protected final PostfixMathCommand	fun

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

curNumberOfParameters, name, NaN, numberOfParameters

Constructor Summary

Constructors

Constructor	Description
NullWrappedPfmc(PostfixMathCommand fun)

Method Summary

Modifier and Type	Method	Description
boolean	checkNumberOfParameters(int n)	Checks the number of parameters of the function.
int	getNumberOfParameters()	Return the required number of parameters.
PostfixMathCommandI	getRoot()	Get to function which this function wraps.
void	run(Stack<Object> stack)	Throws an exception because this method should never be called under normal circumstances.
void	setCurNumberOfParameters(int n)	Sets the number of current number of parameters used in the next call of run().
void	setName(String name)	Sets the name of the function used for error messages

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

asArray, asBool, asDouble, asInt, asLong, asStrictInt, asString, getName, toString, toString

Methods inherited from class java.lang.Object

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

Field Details

fun

protected final PostfixMathCommand fun

Constructor Details

NullWrappedPfmc

public NullWrappedPfmc(PostfixMathCommand fun)

Parameters:

fun -

Method Details

checkNumberOfParameters

public boolean checkNumberOfParameters(int n)

Description copied from class: PostfixMathCommand

Checks the number of parameters of the function. Functions which set numberOfParameter=-1 should overload this method

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.

getNumberOfParameters

public int getNumberOfParameters()

Description copied from class: PostfixMathCommand

Return the required number of parameters.

Specified by:

getNumberOfParameters in interface PostfixMathCommandI

Overrides:

getNumberOfParameters in class PostfixMathCommand

Returns:

allowable number of parameters, -1 if a variable number is allowed

setCurNumberOfParameters

public void setCurNumberOfParameters(int n)

Description copied from class: PostfixMathCommand

Sets the number of current number of parameters used in the next call of run(). This method is only called when the reqNumberOfParameters is -1.

Specified by:

setCurNumberOfParameters in interface PostfixMathCommandI

Overrides:

setCurNumberOfParameters in class PostfixMathCommand

Parameters:

n - number of parameter for next call of function

setName

public void setName(String name)

Description copied from interface: PostfixMathCommandI

Sets the name of the function used for error messages

Specified by:

setName in interface PostfixMathCommandI

Overrides:

setName in class PostfixMathCommand

Parameters:

name - the function name

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".

run

public void run(Stack<Object> stack)
         throws EvaluationException

Description copied from class: PostfixMathCommand

Throws an exception because this method should never be called under normal circumstances. Each function should use its own run() method for evaluating the function. This includes popping off the parameters from the stack, and pushing the result back on the stack.

Specified by:

run in interface PostfixMathCommandI

Overrides:

run in class PostfixMathCommand

Parameters:

stack - arguments for function

Throws:

EvaluationException - if function cannot be evaluated