agi.foundation.coordinates

(agi.foundation.models-2024r3.jar)

Class ReferenceFrameAdapter

java.lang.Object

agi.foundation.infrastructure.DefinitionalObject

agi.foundation.coordinates.StateElementAdapterDefinition

agi.foundation.coordinates.TransformationalStateElementAdapterDefinition

agi.foundation.coordinates.ReferenceFrameAdapter

All Implemented Interfaces:

ICloneWithContext, IEnumerateDependencies, IEquatableDefinition, IFreezable

public class ReferenceFrameAdapter
extends TransformationalStateElementAdapterDefinition

The StateElementAdapter definition for the simple case when the element's definitional object and its defined in object are just a ReferenceFrame. Generally this will be used for various Point types.

This type will create an adapter that will extract a Motion1 of the specified element from the first ITimeBasedState, perform a ReferenceFrame transformation on it, and save that transformed Motion1 to the second state.

If you have some custom point element getting propagated, create a StateElementAdapterDefinition that handles your unique element definition. But have your GetAdapter method construct an instance of this factory and return this types adapter.

The actual adapter will detect if the previous and current frames are the same, and no transformation will be done in that case (to prevent round trip errors).

Constructor Summary

Constructors

Modifier	Constructor and Description
	ReferenceFrameAdapter() Initializes a new instance.
protected	ReferenceFrameAdapter(ReferenceFrameAdapter existingInstance, CopyContext context) Initializes a new instance as a copy of an existing instance.
	ReferenceFrameAdapter(String elementIdentification, ReferenceFrame currentReferenceFrame) Initializes a new instance.

Method Summary

Modifier and Type	Method and Description
protected boolean	checkForSameDefinition(ReferenceFrameAdapter other) Checks to determine if another instance has the same definition as this instance and returns true if it does.
protected boolean	checkForSameDefinition(TransformationalStateElementAdapterDefinition 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.
StateElementAdapter	getAdapter(StateElementAdapterDefinition previousAdapter, EvaluatorGroup group) Creates the adapter defined by this instance.
ReferenceFrame	getCurrentReferenceFrame() Gets the ReferenceFrame that the ElementIdentification (get / set) in the state will be in once the state is adapted.
ReferenceFrame	getPreviousReferenceFrame() Gets the ReferenceFrame that the ElementIdentification (get / set) in the previous state is defined in.
void	setCurrentReferenceFrame(ReferenceFrame value) Sets the ReferenceFrame that the ElementIdentification (get / set) in the state will be in once the state is adapted.
void	setPreviousReferenceFrame(ReferenceFrame value) Sets the ReferenceFrame that the ElementIdentification (get / set) in the previous state is defined in.

Methods inherited from class agi.foundation.coordinates.TransformationalStateElementAdapterDefinition

checkForSameDefinition, enumerateDependencies, getCurrentDefinedIn, getPreviousDefinedIn, setCurrentDefinedIn, setPreviousDefinedIn

Methods inherited from class agi.foundation.coordinates.StateElementAdapterDefinition

checkForSameDefinition, getElementIdentification, setElementIdentification

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, toString, wait, wait, wait

Constructor Detail

ReferenceFrameAdapter

public ReferenceFrameAdapter()

Initializes a new instance. The ElementIdentification (get / set) and CurrentReferenceFrame (get / set) must be set before StateElementAdapterDefinition.getAdapter(agi.foundation.coordinates.StateElementAdapterDefinition, agi.foundation.EvaluatorGroup) is called.

ReferenceFrameAdapter

public ReferenceFrameAdapter(String elementIdentification,
                             ReferenceFrame currentReferenceFrame)

Initializes a new instance.

Parameters:

elementIdentification - The identification of the element to be transformed.

currentReferenceFrame - The ReferenceFrame that the element in the state should be adapted to.

ReferenceFrameAdapter

protected ReferenceFrameAdapter(@Nonnull
                                ReferenceFrameAdapter 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(TransformationalStateElementAdapterDefinition 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 TransformationalStateElementAdapterDefinition

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(ReferenceFrameAdapter 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 ReferenceFrameAdapter.checkForSameDefinition(agi.foundation.coordinates.TransformationalStateElementAdapterDefinition) method.

Overrides:

computeCurrentDefinitionHashCode in class TransformationalStateElementAdapterDefinition

Returns:

The computed hash code.

getCurrentReferenceFrame

public final ReferenceFrame getCurrentReferenceFrame()

Gets the ReferenceFrame that the ElementIdentification (get / set) in the state will be in once the state is adapted.

setCurrentReferenceFrame

public final void setCurrentReferenceFrame(ReferenceFrame value)

Sets the ReferenceFrame that the ElementIdentification (get / set) in the state will be in once the state is adapted.

getPreviousReferenceFrame

public final ReferenceFrame getPreviousReferenceFrame()

Gets the ReferenceFrame that the ElementIdentification (get / set) in the previous state is defined in. It is best to configure whatever is calling StateElementAdapterDefinition.getAdapter(agi.foundation.coordinates.StateElementAdapterDefinition, agi.foundation.EvaluatorGroup) to pass in an old adapter. If there is no old defined in to work with, then the CurrentReferenceFrame (get / set) will be used for both the current and previous. This only needs to be set if it there is no previous adapter to use when the computation options (evaluators, propagators...) are created. If this is set, then it should take priority over the adapter passed into StateElementAdapterDefinition.getAdapter(agi.foundation.coordinates.StateElementAdapterDefinition, agi.foundation.EvaluatorGroup)

setPreviousReferenceFrame

public final void setPreviousReferenceFrame(ReferenceFrame value)

Sets the ReferenceFrame that the ElementIdentification (get / set) in the previous state is defined in. It is best to configure whatever is calling StateElementAdapterDefinition.getAdapter(agi.foundation.coordinates.StateElementAdapterDefinition, agi.foundation.EvaluatorGroup) to pass in an old adapter. If there is no old defined in to work with, then the CurrentReferenceFrame (get / set) will be used for both the current and previous. This only needs to be set if it there is no previous adapter to use when the computation options (evaluators, propagators...) are created. If this is set, then it should take priority over the adapter passed into StateElementAdapterDefinition.getAdapter(agi.foundation.coordinates.StateElementAdapterDefinition, agi.foundation.EvaluatorGroup)

getAdapter

public StateElementAdapter getAdapter(StateElementAdapterDefinition previousAdapter,
                                      EvaluatorGroup group)

Creates the adapter defined by this instance. Since adapters are meant to transition from one context to another, the previous adapter is passed in to finish the configuration. If it is not needed for your particular adapter it can be ignored.

Specified by:

getAdapter in class StateElementAdapterDefinition

Parameters:

previousAdapter - The properly configured previous adapter. Implementations of this method should be able to handle cases where the previousAdapter is of the same or compatible type. For example, a ReferenceFrameAdapter must be able to handle when another ReferenceFrameAdapter is passed in as the previousAdapter. If the types are incompatible, then this method should throw an exception as it is a sign that something is incorrectly configured. When possible, design your adapters to work properly even if this parameter is null. Consider adding extra properties to the derived type, or have a well defined default behavior if the previousAdapter is null.

group - The EvaluatorGroup to use when constructing any needed evaluators.

Returns:

The configured StateElementAdapter.