agi.foundation.access

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

Class LinkPath

java.lang.Object

agi.foundation.compatibility.BaseCollection<T>

agi.foundation.infrastructure.DefinitionalObjectCollection<IServiceProvider>

agi.foundation.access.LinkPath

All Implemented Interfaces:

ICloneWithContext, IEnumerateDependencies, IEquatableDefinition, IFreezable, Iterable<IServiceProvider>, Collection<IServiceProvider>, List<IServiceProvider>

public class LinkPath
extends DefinitionalObjectCollection<IServiceProvider>

Describes a path through one or more links (such as LinkInstantaneous or LinkSpeedOfLight).

A LinkPath is meant to represent a single directed path from an IServiceProvider at the beginning to the IServiceProvider at the end of the path. However, the 'direction' of the path may represent the path from transmission to reception OR reception to transmission, depending on whether a Transmitter or Receiver appears first in the path.

Constructor Summary

Constructors

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

Method Summary

Modifier and Type	Method and Description
protected boolean	checkForSameDefinition(DefinitionalObjectCollection<IServiceProvider> other) Checks to determine if another instance has the same definition as this instance and returns true if it does.
protected boolean	checkForSameDefinition(LinkPath 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.
LinkDelayEvaluator	getLinkPathDelayEvaluator(EvaluatorGroup group, LinkRole roleOfTimeObserver) Creates a LinkDelayEvaluator which evaluates the time delay offset from the initial service provider to the final service provider in the path.
void	reverse() Reverses this path.

Methods inherited from class agi.foundation.infrastructure.DefinitionalObjectCollection

addRange, clearItems, enumerateDependencies, freeze, freezeAggregatedObjects, getDefinitionHashCode, getIsFrozen, insertItem, isSameDefinition, removeItem, setItem, throwIfFrozen

Methods inherited from class agi.foundation.compatibility.BaseCollection

add, add, addAll, addAll, clear, contains, containsAll, get, getItems, indexOf, isEmpty, iterator, lastIndexOf, listIterator, listIterator, remove, remove, removeAll, retainAll, set, size, subList, toArray, toArray

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.List

equals, hashCode, replaceAll, sort, spliterator

Methods inherited from interface java.util.Collection

parallelStream, removeIf, stream

Methods inherited from interface java.lang.Iterable

forEach

Constructor Detail

LinkPath

public LinkPath()

Initializes a new instance.

LinkPath

protected LinkPath(@Nonnull
                   LinkPath 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

Overrides:

clone in class DefinitionalObjectCollection<IServiceProvider>

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(DefinitionalObjectCollection<IServiceProvider> other)

Description copied from class: DefinitionalObjectCollection

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).

Overrides:

checkForSameDefinition in class DefinitionalObjectCollection<IServiceProvider>

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(LinkPath 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 LinkPath.checkForSameDefinition(agi.foundation.infrastructure.DefinitionalObjectCollection<agi.foundation.IServiceProvider>) method.

Overrides:

computeCurrentDefinitionHashCode in class DefinitionalObjectCollection<IServiceProvider>

Returns:

The computed hash code.

reverse

public final void reverse()

Reverses this path.

getLinkPathDelayEvaluator

@Nonnull
public final LinkDelayEvaluator getLinkPathDelayEvaluator(@Nonnull
                                                                    EvaluatorGroup group,
                                                                    @Nonnull
                                                                    LinkRole roleOfTimeObserver)

Creates a LinkDelayEvaluator which evaluates the time delay offset from the initial service provider to the final service provider in the path.

If the roleOfTimeObserver is LinkRole.RECEIVER, the resulting delay evaluator will produce the offset to the time of first transmission when given the time of reception. If the roleOfTimeObserver is LinkRole.TRANSMITTER, the resulting delay evaluator will produce the offset to the time of final reception when given the time of first transmission.

Parameters:

group - The evaluator group in which to create link delay evaluators.

roleOfTimeObserver - The role of the time observer. If the role is receiving, the delay is negative. If the role is transmitting, the delay is positive.

Returns:

The link delay offset evaluator from the first link to the last in this collection. If there are no links in the collection, the evaluator produces no delay.

Throws:

IllegalStateException - Thrown when this link path does not continuously connect from beginning to end, or when the path is not correctly directed in a single direction from beginning to end. This could occur if two links in the chain both point to a single receiver object, rather than one transmitting to the other, which in turn transmits to another, etc.