agi.foundation.stoppingconditions

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

Class EpochSecondsStoppingCondition

java.lang.Object

agi.foundation.infrastructure.DefinitionalObject

agi.foundation.stoppingconditions.StoppingCondition

agi.foundation.stoppingconditions.EpochSecondsStoppingCondition

All Implemented Interfaces:

ICloneWithContext, IEnumerateDependencies, IEquatableDefinition, IFreezable

public class EpochSecondsStoppingCondition
extends StoppingCondition

A StoppingCondition whose threshold is the number of seconds past an arbitrary epoch.

Note that the threshold tolerance for this stopping condition is set to Constants.Epsilon9 by default. That is the worst case for a Duration's precision.

Constructor Summary

Constructors

Modifier	Constructor and Description
	EpochSecondsStoppingCondition() Initializes a new instance.
protected	EpochSecondsStoppingCondition(EpochSecondsStoppingCondition existingInstance, CopyContext context) Initializes a new instance as a copy of an existing instance.
	EpochSecondsStoppingCondition(JulianDate epoch, JulianDate threshold) Initializes a new instance.

Method Summary

Modifier and Type	Method and Description
protected boolean	checkForSameDefinition(EpochSecondsStoppingCondition other) Checks to determine if another instance has the same definition as this instance and returns true if it does.
protected boolean	checkForSameDefinition(StoppingCondition 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.
ValueDefinition<Double>	createDoubleThreshold() Creates a ValueDefinition of type double.
void	enumerateDependencies(DependencyEnumerator enumerator) Enumerates the dependencies of this object by calling DependencyEnumerator#enumerate(T) for each object that this object directly depends upon.
JulianDate	getEpoch() Gets the epoch used in computing the number of epoch seconds for this StoppingCondition.
StoppingConditionEvaluator	getEvaluator(EvaluatorGroup group) Gets a StoppingConditionEvaluator for use in the NumericalPropagator.
ValueDefinition<JulianDate>	getThreshold() Gets the threshold of this StoppingCondition as a date.
void	setEpoch(JulianDate value) Sets the epoch used in computing the number of epoch seconds for this StoppingCondition.
void	setThreshold(ValueDefinition<JulianDate> value) Sets the threshold of this StoppingCondition as a date.

Methods inherited from class agi.foundation.stoppingconditions.StoppingCondition

checkForSameDefinition, freezeAggregatedObjects, getAngularSetting, getConstraints, getEnabled, getFunctionTolerance, getName, getRequireFunctionTolerance, getSatisfiedCallback, getStopOnEventNumber, getTypeOfStoppingCondition, setAngularSetting, setEnabled, setFunctionTolerance, setName, setRequireFunctionTolerance, setSatisfiedCallback, setStopOnEventNumber, setTypeOfStoppingCondition, validateProperties

Methods inherited from class agi.foundation.infrastructure.DefinitionalObject

areSameDefinition, areSameDefinition, areSameDefinition, areSameDefinition, areSameDefinition, collectionItemsAreSameDefinition, collectionItemsAreSameDefinition, collectionItemsAreSameDefinition, dictionaryItemsAreSameDefinition, freeze, 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

EpochSecondsStoppingCondition

public EpochSecondsStoppingCondition()

Initializes a new instance.

EpochSecondsStoppingCondition

public EpochSecondsStoppingCondition(@Nonnull
                                     JulianDate epoch,
                                     @Nonnull
                                     JulianDate threshold)

Initializes a new instance.

Parameters:

epoch - The epoch to use when computing epoch seconds.

threshold - The final date that determines when this condition is satisfied.

EpochSecondsStoppingCondition

protected EpochSecondsStoppingCondition(@Nonnull
                                        EpochSecondsStoppingCondition 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(StoppingCondition 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 StoppingCondition

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(EpochSecondsStoppingCondition 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 EpochSecondsStoppingCondition.checkForSameDefinition(agi.foundation.stoppingconditions.StoppingCondition) method.

Overrides:

computeCurrentDefinitionHashCode in class StoppingCondition

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 StoppingCondition

Parameters:

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

getEvaluator

public StoppingConditionEvaluator getEvaluator(EvaluatorGroup group)

Gets a StoppingConditionEvaluator for use in the NumericalPropagator.

Specified by:

getEvaluator in class StoppingCondition

Parameters:

group - The group to use to initialize any evaluators that will be used by the stopping condition.

Returns:

An evaluator for this StoppingCondition.

Throws:

PropertyInvalidException - Thrown when StopOnEventNumber (get / set) is not positive.

PropertyInvalidException - Thrown when FunctionTolerance (get / set) is negative.

PropertyInvalidException - Thrown when Threshold (get / set) is null.

PropertyInvalidException - Thrown when StopOnEventNumber (get / set) is not 1.

getThreshold

public final ValueDefinition<JulianDate> getThreshold()

Gets the threshold of this StoppingCondition as a date.

setThreshold

public final void setThreshold(ValueDefinition<JulianDate> value)

Sets the threshold of this StoppingCondition as a date.

getEpoch

@Nonnull
public final JulianDate getEpoch()

Gets the epoch used in computing the number of epoch seconds for this StoppingCondition. By default this is TimeConstants.J2000.

setEpoch

public final void setEpoch(@Nonnull
                           JulianDate value)

Sets the epoch used in computing the number of epoch seconds for this StoppingCondition. By default this is TimeConstants.J2000.

createDoubleThreshold

public ValueDefinition<Double> createDoubleThreshold()

Creates a ValueDefinition of type double. If the derived StoppingCondition defines its threshold to be of a different type than a double, it can use a ValueDefinition of that other type in its StoppingConditionEvaluator. However it is required that the threshold can be represented as a double and this must return such a value. If the specified StoppingCondition threshold is just a ValueDefinition of type double, that property can simply be returned here.

Specified by:

createDoubleThreshold in class StoppingCondition

Returns:

The threshold as a ValueDefinition where the type is a double.