agi.foundation.segmentpropagation

(agi.foundation.segmentpropagation-2024r2.jar)

Class SwitchableSegment

java.lang.Object

agi.foundation.infrastructure.DefinitionalObject

agi.foundation.segmentpropagation.SegmentDefinition

agi.foundation.segmentpropagation.SwitchableSegment

All Implemented Interfaces:

ICloneWithContext, IEnumerateDependencies, IEquatableDefinition, IFreezable

public class SwitchableSegment
extends SegmentDefinition

A SegmentDefinition that can switch between two segments.

Constructor Summary

Constructors

Modifier	Constructor and Description
	SwitchableSegment() Initializes a new instance.
	SwitchableSegment(SegmentDefinition primarySegment, SegmentDefinition alternateSegment) Initializes a new instance.
protected	SwitchableSegment(SwitchableSegment existingInstance, CopyContext context) Initializes a new instance as a copy of an existing instance.

Method Summary

Modifier and Type	Method and Description
void	addPropagationFinishedEvent(EventHandler<SegmentPropagationEventArgs> value) An event that gets raised when propagation is complete.
protected boolean	checkForSameDefinition(SegmentDefinition other) Checks to determine if another instance has the same definition as this instance and returns true if it does.
protected boolean	checkForSameDefinition(SwitchableSegment other) Checks to determine if another instance has the same definition as this instance and returns true if it does.
Object	clone(CopyContext context) Clones this object using the specified context.
protected int	computeCurrentDefinitionHashCode() Computes a hash code based on the current properties of this object.
protected SegmentPropagator	createSegmentPropagator(EvaluatorGroup group, SegmentDefinition previousSegment) Creates, configures, and returns the SegmentPropagator for this segment.
void	enumerateDependencies(DependencyEnumerator enumerator) Enumerates the dependencies of this object by calling DependencyEnumerator#enumerate(T) for each object that this object directly depends upon.
SegmentDefinition	getAlternateSegment() Gets the alternate segment.
Object	getDefinedIn(String element) Gets the object (for example, a ReferenceFrame, an Axes, etc.) in which the specified element is defined in.
StateElementAdapterDefinition	getElementAdapter(String element) Returns the adapter for the given state element.
List<String>	getElements() Gets the names of all of the elements that this segment is propagating.
boolean	getPassAllElementsToNextSegment() Gets a value indicating whether the segment is such that it will not define any Elements (get) or StateElementAdapters.
SegmentDefinition	getPrimarySegment() Gets the primary segment.
ValueDefinition<SegmentDefinition>	getSegmentToRun() Gets the definition of the evaluator that will tell the SegmentPropagator which segment to run.
SwitchableSegmentOption	getSegmentToRunInitially() Gets which segment should be propagated initially.
ValueParameter<SegmentDefinition>	getSegmentToRunParameter() Gets the ValueParameter that can be used to change which SegmentDefinition gets propagated.
void	removePropagationFinishedEvent(EventHandler<SegmentPropagationEventArgs> value) An event that gets raised when propagation is complete.
void	setAlternateSegment(SegmentDefinition value) Sets the alternate segment.
boolean	setElementAndAdapter(StateElementAdapterDefinition adapter) Normally this method would set the StateElementAdapterDefinition on this segment, but instead you must set the adapter on either the PrimarySegment (get / set) or AlternateSegment (get / set).
void	setPrimarySegment(SegmentDefinition value) Sets the primary segment.
void	setSegmentToRunInitially(SwitchableSegmentOption value) Sets which segment should be propagated initially.

Methods inherited from class agi.foundation.segmentpropagation.SegmentDefinition

checkForSameDefinition, containsElement, getName, getNextStateBehavior, getPropagationDirection, getSegmentPropagator, getSegmentPropagator, getSegmentPropagator, getSegmentPropagator, removeElement, setName, setNextStateBehavior, setPropagationDirection, toString

Methods inherited from class agi.foundation.infrastructure.DefinitionalObject

areSameDefinition, areSameDefinition, areSameDefinition, areSameDefinition, areSameDefinition, collectionItemsAreSameDefinition, collectionItemsAreSameDefinition, collectionItemsAreSameDefinition, dictionaryItemsAreSameDefinition, freeze, freezeAggregatedObjects, getCollectionHashCode, getCollectionHashCode, getCollectionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDictionaryHashCode, getIsFrozen, isSameDefinition, throwIfFrozen

Methods inherited from class java.lang.Object

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

Constructor Detail

SwitchableSegment

public SwitchableSegment()

Initializes a new instance. PrimarySegment (get / set) and AlternateSegment (get / set) must both be set before calling SegmentDefinition.getSegmentPropagator(EvaluatorGroup,SegmentDefinition).

SwitchableSegment

public SwitchableSegment(SegmentDefinition primarySegment,
                         SegmentDefinition alternateSegment)

Initializes a new instance.

Parameters:

primarySegment - The primary segment.

alternateSegment - The alternate segment. By default this will be the segment that this overall segment will propagate.

SwitchableSegment

protected SwitchableSegment(@Nonnull
                            SwitchableSegment existingInstance,
                            @Nonnull
                            CopyContext context)

Initializes a new instance as a copy of an existing instance.

See ICloneWithContext.clone(CopyContext) for more information about how to implement this constructor in a derived class.

Parameters:

existingInstance - The existing instance to copy.

context - A CopyContext that controls the depth of the copy.

Throws:

ArgumentNullException - Thrown when existingInstance or context is null.

Method Detail

clone

public Object clone(CopyContext context)

Clones this object using the specified context.

This method should be implemented to call a copy constructor on the class of the object being cloned. The copy constructor should take the CopyContext as a parameter in addition to the existing instance to copy. The copy constructor should first call CopyContext.addObjectMapping(T, T) to identify the newly constructed instance as a copy of the existing instance. It should then copy all fields, using CopyContext.updateReference(T) to copy any reference fields.

A typical implementation of ICloneWithContext:

public static class MyClass implements ICloneWithContext {
    public MyClass(MyClass existingInstance, CopyContext context) {
        context.addObjectMapping(existingInstance, this);
        someReference = context.updateReference(existingInstance.someReference);
    }

    @Override
    public final Object clone(CopyContext context) {
        return new MyClass(this, context);
    }

    private Object someReference;
}

In general, all fields that are reference types should be copied with a call to CopyContext.updateReference(T). There are a couple of exceptions:

1. Fields that are aggregate parts of the object should always be copied. A referenced object is an aggregate if properties or methods on the object being copied can modify the externally-visible value of the referenced object.
2. If the semantics of the referenced object require that it have a single parent, owner, context, etc., and the object being copied is that parent, owner, or context, then the referenced object should always be copied.

If one of these exceptions applies, the CopyContext should be given an opportunity to update the reference before the reference is copied explicitly. Use CopyContext.updateReference(T) to update the reference. If CopyContext.updateReference(T) returns the original object, indicating that the context does not have a replacement registered, then copy the object manually by invoking a Clone method, a copy constructor, or by manually constructing a new instance and copying the values.

alwaysCopy = context.updateReference(existingInstance.alwaysCopy);
if (existingInstance.alwaysCopy != null && alwaysCopy == existingInstance.alwaysCopy) {
    alwaysCopy = (AlwaysCopy) existingInstance.alwaysCopy.clone(context);
}

If you are implementing an evaluator (a class that implements IEvaluator), the IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) method shares some responsibilities with the copy context constructor. Code duplication can be avoided by doing the following:

1. For references to other evaluators ONLY, simply assign the reference in the constructor instead of calling CopyContext.updateReference(T). You should still call CopyContext.updateReference(T) on any references to non-evaluators.
2. Call IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) as the last line in the constructor and pass it the same CopyContext passed to the constructor.
3. Implement IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) as normal. See the reference documentation for IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) for more information on implementing that method.

public MyClass(MyClass existingInstance, CopyContext context) {
    super(existingInstance, context);
    someReference = context.updateReference(existingInstance.someReference);
    evaluatorReference = existingInstance.evaluatorReference;
    updateEvaluatorReferences(context);
}

@Override
public void updateEvaluatorReferences(CopyContext context) {
    evaluatorReference = context.updateReference(evaluatorReference);
}

@Override
public Object clone(CopyContext context) {
    return new MyClass(this, context);
}

private Object someReference;
private IEvaluator evaluatorReference;

Specified by:

clone in interface ICloneWithContext

Specified by:

clone in class DefinitionalObject

Parameters:

context - The context to use to perform the copy.

Returns:

A new instance which is a copy of this object.

checkForSameDefinition

protected final boolean checkForSameDefinition(SegmentDefinition other)

Checks to determine if another instance has the same definition as this instance and returns true if it does. Derived classes MUST override this method and check all new fields introduced by the derived class for definitional equivalence. It is NOT necessary to check base class fields because the base class will already have done that. When overriding this method, you should NOT call the base implementation because it will return false for all derived-class instances. Derived classes should check the type of other to preserve the symmetric nature of IEquatableDefinition.isSameDefinition(java.lang.Object).

Specified by:

checkForSameDefinition in class SegmentDefinition

Parameters:

other - The other instance to compare to this one.

Returns:

true if the two objects are defined equivalently; otherwise false.

checkForSameDefinition

protected boolean checkForSameDefinition(@Nullable
                                         SwitchableSegment other)

Checks to determine if another instance has the same definition as this instance and returns true if it does. Derived classes MUST override this method and check all new fields introduced by the derived class for definitional equivalence. It is NOT necessary to check base class fields because the base class will already have done that. When overriding this method, you should NOT call the base implementation because it will return false for all derived-class instances. Derived classes should check the type of other to preserve the symmetric nature of IEquatableDefinition.isSameDefinition(java.lang.Object).

Parameters:

other - The other instance to compare to this one.

Returns:

true if the two objects are defined equivalently; otherwise false.

computeCurrentDefinitionHashCode

protected int computeCurrentDefinitionHashCode()

Computes a hash code based on the current properties of this object. Derived classes MUST override this method and compute a hash code that combines: a unique hash code seed, the base implementation result, and the hash codes of all new fields introduced by the derived class which are used in the SwitchableSegment.checkForSameDefinition(agi.foundation.segmentpropagation.SegmentDefinition) method.

Overrides:

computeCurrentDefinitionHashCode in class SegmentDefinition

Returns:

The computed hash code.

enumerateDependencies

public void enumerateDependencies(DependencyEnumerator enumerator)

Enumerates the dependencies of this object by calling DependencyEnumerator#enumerate(T) for each object that this object directly depends upon. Derived classes which contain additional dependencies MUST override this method, call the base implementation, and enumerate dependencies introduced by the derived class.

Specified by:

enumerateDependencies in interface IEnumerateDependencies

Overrides:

enumerateDependencies in class DefinitionalObject

Parameters:

enumerator - The enumerator that is informed of the dependencies of this object.

setElementAndAdapter

public boolean setElementAndAdapter(StateElementAdapterDefinition adapter)

Normally this method would set the StateElementAdapterDefinition on this segment, but instead you must set the adapter on either the PrimarySegment (get / set) or AlternateSegment (get / set).

Overrides:

setElementAndAdapter in class SegmentDefinition

Parameters:

adapter - The StateElementAdapter.

Returns:

false.

getDefinedIn

public Object getDefinedIn(String element)

Gets the object (for example, a ReferenceFrame, an Axes, etc.) in which the specified element is defined in. This can return null if there is no such object. When overriding this method, you generally should not call the base method, instead the derived segment should keep track of the elements and defined in objects itself.

Overrides:

getDefinedIn in class SegmentDefinition

Parameters:

element - The identification of the element.

Returns:

The defined in object for the element.

getElementAdapter

public StateElementAdapterDefinition getElementAdapter(String element)

Returns the adapter for the given state element. The StateElementAdapters handle the various transformations of the propagated elements between segments (for example, if the integration frame of a point being propagated changes from one segment to another, the adapter is what handles that transformation between segment). All elements propagated by this segment must have an adapter returned by this method (even if that adapter simply returns the original state). If multiple segments are being propagated by this segment (as a SegmentList would), this must return the adapter of the StateElementAdapter of the element for the final known segment getting propagated.

In general, the concrete SegmentDefinition should have a list of the adapter factory instances that are valid for this segment, and then this method would get the element definition object from this segments configuration.

Overrides:

getElementAdapter in class SegmentDefinition

Parameters:

element - The element whose StateElementAdapter is needed.

Returns:

The adapter with the element defined-in set, or null if there is no such factory.

createSegmentPropagator

protected SegmentPropagator createSegmentPropagator(EvaluatorGroup group,
                                                    SegmentDefinition previousSegment)

Creates, configures, and returns the SegmentPropagator for this segment. This method should check that all of the required properties on the concrete instance are configured properly before constructing the SegmentPropagator to be returned.

Specified by:

createSegmentPropagator in class SegmentDefinition

Parameters:

group - The group to use during creation.

previousSegment - The previous segment. Some segments will require the previousSegment to be set, whereas other will require that the previous segment not be null, whereas others will only use information from it if provided. It is up to you writing a concrete type to enforce what makes sense for your particular segment in this method.

Returns:

The propagator for this segment.

getElements

@Nonnull
public List<String> getElements()

Gets the names of all of the elements that this segment is propagating.

Unless the logic of a derived segment requires it, there is no requirement that the same elements get propagated from segment to segment (for example, you can propagate a satellite and the booster that got it into orbit. When the booster reenters the atmosphere, you do not have to keep that element around in later segments). However values that you want to be propagated from segment to segment must have the same name (continuing the example, the name of the satellite getting propagated needs to be consistent from segment to segment).

Overrides:

getElements in class SegmentDefinition

addPropagationFinishedEvent

public void addPropagationFinishedEvent(EventHandler<SegmentPropagationEventArgs> value)

An event that gets raised when propagation is complete.

Specified by:

addPropagationFinishedEvent in class SegmentDefinition

removePropagationFinishedEvent

public void removePropagationFinishedEvent(EventHandler<SegmentPropagationEventArgs> value)

An event that gets raised when propagation is complete.

Specified by:

removePropagationFinishedEvent in class SegmentDefinition

getSegmentToRunInitially

@Nonnull
public final SwitchableSegmentOption getSegmentToRunInitially()

Gets which segment should be propagated initially. Defaults to SwitchableSegmentOption.ALTERNATE.

setSegmentToRunInitially

public final void setSegmentToRunInitially(@Nonnull
                                           SwitchableSegmentOption value)

Sets which segment should be propagated initially. Defaults to SwitchableSegmentOption.ALTERNATE.

getPrimarySegment

public final SegmentDefinition getPrimarySegment()

Gets the primary segment. For all cases where there is ambiguity between what settings the SwitchableSegment will use, this segment may be assumed to contain those settings. For example, the final states generated by the overall SwitchableSegment will be in the defined-in objects (ReferenceFrame, Axes...) of this segment.

setPrimarySegment

public final void setPrimarySegment(SegmentDefinition value)

Sets the primary segment. For all cases where there is ambiguity between what settings the SwitchableSegment will use, this segment may be assumed to contain those settings. For example, the final states generated by the overall SwitchableSegment will be in the defined-in objects (ReferenceFrame, Axes...) of this segment.

getAlternateSegment

public final SegmentDefinition getAlternateSegment()

Gets the alternate segment. By default, this is the segment that will be propagated and then swapped out. The results will be in the defined-in's (ReferenceFrame, Axes) of the PrimarySegment (get / set).

setAlternateSegment

public final void setAlternateSegment(SegmentDefinition value)

Sets the alternate segment. By default, this is the segment that will be propagated and then swapped out. The results will be in the defined-in's (ReferenceFrame, Axes) of the PrimarySegment (get / set).

getSegmentToRunParameter

public final ValueParameter<SegmentDefinition> getSegmentToRunParameter()

Gets the ValueParameter that can be used to change which SegmentDefinition gets propagated.

getSegmentToRun

public final ValueDefinition<SegmentDefinition> getSegmentToRun()

Gets the definition of the evaluator that will tell the SegmentPropagator which segment to run.

getPassAllElementsToNextSegment

public boolean getPassAllElementsToNextSegment()

Gets a value indicating whether the segment is such that it will not define any Elements (get) or StateElementAdapters. Such a segment typically affects the control flow of multiple segments instead of propagating state elements. By default this is false, but if the specific derived segment can use the previous segment's adapters, override this property to always return true. Even if this is true some segments may require adapters to be set with the SwitchableSegment.setElementAndAdapter(agi.foundation.coordinates.StateElementAdapterDefinition) method.

Overrides:

getPassAllElementsToNextSegment in class SegmentDefinition