Package org.opentrafficsim.road.gtu.lane.perception

Class AbstractPerceptionReiterable<H extends Headway,U>

java.lang.Object

org.opentrafficsim.road.gtu.lane.perception.AbstractPerceptionReiterable<H,U>

Type Parameters:

H - headway type

U - underlying object type

All Implemented Interfaces:

Iterable<H>, PerceptionCollectable<H,U>, PerceptionIterable<H>

Direct Known Subclasses:

AbstractPerceptionIterable, MultiLanePerceptionIterable

public abstract class AbstractPerceptionReiterable<H extends Headway,U>
extends Object
implements PerceptionCollectable<H,U>

This class uses a single primary iterator which a subclass defines, and makes sure that all elements are only looked up and created once. It does so by storing the elements in a linked list. All calls to iterator() return an iterator which iterates over the linked list. If an iterator runs to the end of the linked list, the primary iterator is requested to add an element if it has one.

Copyright (c) 2013-2022 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved.
BSD-style license. See OpenTrafficSim License.

Version:

$Revision$, $LastChangedDate$, by $Author$, initial version 20 feb. 2018

Author:

Alexander Verbraeck, Peter Knoppers, Wouter Schakel

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
class	AbstractPerceptionReiterable.PerceptionIterator	This iterator is returned to callers of the iterator() method.
protected class	AbstractPerceptionReiterable.PrimaryIteratorEntry	Class for primaryIterator() to return, implemented in subclasses.

Nested classes/interfaces inherited from interface org.opentrafficsim.road.gtu.lane.perception.PerceptionCollectable

PerceptionCollectable.Intermediate<I>, PerceptionCollectable.PerceptionAccumulator<U,I>, PerceptionCollectable.PerceptionCollector<C,U,I>, PerceptionCollectable.PerceptionFinalizer<C,I>, PerceptionCollectable.UnderlyingDistance<U>

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AbstractPerceptionReiterable(LaneBasedGTU perceivingGtu)	Constructor.

Method Summary

Modifier and Type	Method	Description
(package private) void	addNext(AbstractPerceptionReiterable.PrimaryIteratorEntry next)	Adds an iterator entry to the internal linked list.
(package private) org.opentrafficsim.road.gtu.lane.perception.AbstractPerceptionReiterable.SecondaryIteratorEntry	assureNext(org.opentrafficsim.road.gtu.lane.perception.AbstractPerceptionReiterable.SecondaryIteratorEntry next, org.opentrafficsim.road.gtu.lane.perception.AbstractPerceptionReiterable.SecondaryIteratorEntry lastReturned)	Helper method that assures that a next entry is available, if the primary iterator has a next value.
<C,I> C	collect(Supplier<I> identity, PerceptionCollectable.PerceptionAccumulator<? super U,I> accumulator, PerceptionCollectable.PerceptionFinalizer<C,I> finalizer)	Collect the underlying objects in to a perceived result.
H	first()	Returns the first element.
protected LaneBasedGTU	getGtu()	Returns the GTU.
(package private) Iterator<AbstractPerceptionReiterable.PrimaryIteratorEntry>	getPrimaryIterator()	Returns the primary iterator.
boolean	isEmpty()	Returns whether this iterable is empty.
Iterator<H>	iterator()
protected abstract H	perceive(LaneBasedGTU perceivingGtu, U object, Length distance)	Returns a perceived version of the underlying object.
protected abstract Iterator<AbstractPerceptionReiterable.PrimaryIteratorEntry>	primaryIterator()	Returns the primary iterator.
Iterator<U>	underlying()	Returns an iterator over the underlying objects.
Iterator<PerceptionCollectable.UnderlyingDistance<U>>	underlyingWithDistance()	Returns an iterator over the underlying objects coupled with the distance.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Methods inherited from interface org.opentrafficsim.road.gtu.lane.perception.PerceptionCollectable

collect

Constructor Detail

AbstractPerceptionReiterable

protected AbstractPerceptionReiterable(LaneBasedGTU perceivingGtu)

Constructor.

Parameters:

perceivingGtu - LaneBasedGTU; perceiving GTU

Method Detail

getGtu

protected LaneBasedGTU getGtu()

Returns the GTU.

Returns:

LaneBasedGTU; GTU

getPrimaryIterator

final Iterator<AbstractPerceptionReiterable.PrimaryIteratorEntry> getPrimaryIterator()

Returns the primary iterator.

Returns:

Iterator; primary iterator

primaryIterator

protected abstract Iterator<AbstractPerceptionReiterable.PrimaryIteratorEntry> primaryIterator()

Returns the primary iterator. This method is called once by AbstractPerceptionReiterable.

Returns:

Iterator; primary iterator

perceive

protected abstract H perceive(LaneBasedGTU perceivingGtu,
                              U object,
                              Length distance)
                       throws GTUException,
                              org.opentrafficsim.base.parameters.ParameterException

Returns a perceived version of the underlying object.

Parameters:

perceivingGtu - LaneBasedGTU; perceiving GTU

object - U; underlying object

distance - Length; distance to the object

Returns:

H; perceived version of the underlying object

Throws:

GTUException - on exception

org.opentrafficsim.base.parameters.ParameterException - on invalid parameter value or missing parameter

first

public final H first()

Returns the first element.

Specified by:

first in interface PerceptionIterable<H extends Headway>

Returns:

H; first element

addNext

final void addNext(AbstractPerceptionReiterable.PrimaryIteratorEntry next)

Adds an iterator entry to the internal linked list.

Parameters:

next - PrimaryIteratorEntry; next object

isEmpty

public final boolean isEmpty()

Returns whether this iterable is empty.

Specified by:

isEmpty in interface PerceptionIterable<H extends Headway>

Returns:

whether this iterable is empty

iterator

public final Iterator<H> iterator()

Specified by:

iterator in interface Iterable<H extends Headway>

collect

public final <C,I> C collect(Supplier<I> identity,
                                   PerceptionCollectable.PerceptionAccumulator<? super U,I> accumulator,
                                   PerceptionCollectable.PerceptionFinalizer<C,I> finalizer)

Collect the underlying objects in to a perceived result. This methodology is loosely based on Stream.collect().

Specified by:

collect in interface PerceptionCollectable<H extends Headway,U>

Type Parameters:

C - collection result type

I - intermediate type

Parameters:

identity - Supplier<I>; the initial intermediate result value

accumulator - PerceptionAccumulator<? super U, I>; accumulator

finalizer - PerceptionFinalizer<C, I>; finalizer

Returns:

C; collection result

underlying

public Iterator<U> underlying()

Returns an iterator over the underlying objects.

Specified by:

underlying in interface PerceptionCollectable<H extends Headway,U>

Returns:

Iterator<U>; iterator

underlyingWithDistance

public Iterator<PerceptionCollectable.UnderlyingDistance<U>> underlyingWithDistance()

Returns an iterator over the underlying objects coupled with the distance.

Specified by:

underlyingWithDistance in interface PerceptionCollectable<H extends Headway,U>

Returns:

Iterator<UnderlyingDistance<U>>; iterator

assureNext

org.opentrafficsim.road.gtu.lane.perception.AbstractPerceptionReiterable.SecondaryIteratorEntry assureNext(org.opentrafficsim.road.gtu.lane.perception.AbstractPerceptionReiterable.SecondaryIteratorEntry next,
                                                                                                           org.opentrafficsim.road.gtu.lane.perception.AbstractPerceptionReiterable.SecondaryIteratorEntry lastReturned)

Helper method that assures that a next entry is available, if the primary iterator has a next value. This method may be used by any process that derives from the primary iterator.

Parameters:

next - SecondaryIteratorEntry; currently known next entry

lastReturned - SecondaryIteratorEntry; entry of last returned object or value

Returns:

IteratorEntry; next entry