agi.foundation.coordinates

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

Class SimpleAdapter<T>

java.lang.Object

agi.foundation.infrastructure.DefinitionalObject

agi.foundation.coordinates.StateElementAdapterDefinition

agi.foundation.coordinates.SimpleAdapter<T>

Type Parameters:

T - The type of the element that is going to be adapted.

All Implemented Interfaces:

ICloneWithContext, IEnumerateDependencies, IEquatableDefinition, IFreezable

public class SimpleAdapter<T>
extends StateElementAdapterDefinition

A StateElementAdapter that has no defined-in object (such as a ReferenceFrame or Axes). This adapter will extract the T of a specified element from a ITimeBasedState and modify the second ITimeBasedState with the extracted value.

Constructor Summary

Constructors

Modifier	Constructor and Description
	SimpleAdapter() Initializes a new instance.
protected	SimpleAdapter(SimpleAdapter<T> existingInstance, CopyContext context) Initializes a new instance as a copy of an existing instance.
	SimpleAdapter(String elementIdentification) Initializes a new instance.

Method Summary

Modifier and Type	Method and Description
protected boolean	checkForSameDefinition(SimpleAdapter<T> other) Checks to determine if another instance has the same definition as this instance and returns true if it does.
protected boolean	checkForSameDefinition(StateElementAdapterDefinition 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.

Methods inherited from class agi.foundation.coordinates.StateElementAdapterDefinition

checkForSameDefinition, enumerateDependencies, 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

SimpleAdapter

public SimpleAdapter()

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

SimpleAdapter

public SimpleAdapter(String elementIdentification)

Initializes a new instance.

Parameters:

elementIdentification - The element in the state that this operator will work on.

SimpleAdapter

protected SimpleAdapter(@Nonnull
                        SimpleAdapter<T> 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(StateElementAdapterDefinition 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 StateElementAdapterDefinition

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(SimpleAdapter<T> 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 SimpleAdapter.checkForSameDefinition(agi.foundation.coordinates.StateElementAdapterDefinition) method.

Overrides:

computeCurrentDefinitionHashCode in class StateElementAdapterDefinition

Returns:

The computed hash code.

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.