net.sf.jga.fn.adaptor
Class ConditionalGenerator<R>

java.lang.Object
  net.sf.jga.fn.Functor<R>
      net.sf.jga.fn.Generator<R>
          net.sf.jga.fn.adaptor.ConditionalGenerator<R>

All Implemented Interfaces:

java.io.Serializable, Visitable

public class ConditionalGenerator<R>
extends Generator<R>

Generator that tests a condition, executes one of two given functors, and returns the result. The argument used to evaluate the condition will also be passed to whichever functor is executed. This functor implements the traditional ?: operator.

Copyright © 2003-2005 David A. Hall

Author:

David A. Hall

See Also:

Serialized Form

Nested Class Summary

static interface

ConditionalGenerator.Visitor Interface for classes that may interpret a ConditionalGenerator functor.

Constructor Summary

ConditionalGenerator(Generator<java.lang.Boolean> test, Generator<R> trueFn, Generator<R> falseFn)
Builds a ConditionalGenerator functor, given the condition to test, and the two functors that may be executed.

Method Summary

void	accept(Visitor v) Calls the Visitor's visit(ConditionalGenerator) method, if it implements the nested Visitor interface.
R	fn() Given argument x, evaluates test(x); if true, returns trueFn(x), otherwise, returns falseFn(x).
Generator<java.lang.Boolean>	getCondition() Returns the test functors
Generator<R>	getFalseFunctor() Returns the functor that is executed when the condition is false
Generator<R>	getTrueFunctor() Returns the functor that is executed when the condition is true
java.lang.String	toString()

Methods inherited from class net.sf.jga.fn.Generator

bind0th, bindNth, eval

Methods inherited from class net.sf.jga.fn.Functor

composeNth, composeNth, generateNth

Methods inherited from class java.lang.Object

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

Constructor Detail

ConditionalGenerator

public ConditionalGenerator(Generator<java.lang.Boolean> test,
                            Generator<R> trueFn,
                            Generator<R> falseFn)

Builds a ConditionalGenerator functor, given the condition to test, and the two functors that may be executed.

Throws:

java.lang.IllegalArgumentException - if any of the functors is missing

Method Detail

getCondition

public Generator<java.lang.Boolean> getCondition()

Returns the test functors

Returns:

the test functors

getTrueFunctor

public Generator<R> getTrueFunctor()

Returns the functor that is executed when the condition is true

Returns:

the functor that is executed when the condition is true

getFalseFunctor

public Generator<R> getFalseFunctor()

Returns the functor that is executed when the condition is false

Returns:

the functor that is executed when the condition is false

fn

public R fn()

Given argument x, evaluates test(x); if true, returns trueFn(x), otherwise, returns falseFn(x).

Specified by:

fn in class Generator<R>

Returns:

test() ? trueFn() : falseFn()

accept

public void accept(Visitor v)

Calls the Visitor's visit(ConditionalGenerator) method, if it implements the nested Visitor interface.

Specified by:

accept in interface Visitable

Overrides:

accept in class Functor<R>

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object