org.eclipse.ocl.pivot.library

Class AbstractIteration

java.lang.Object

org.eclipse.ocl.pivot.utilities.ValueUtil

org.eclipse.ocl.pivot.library.AbstractFeature

org.eclipse.ocl.pivot.library.AbstractIteration

All Implemented Interfaces:

LibraryFeature, LibraryIteration, LibraryIteration.LibraryIterationExtension

Direct Known Subclasses:

AnyIteration, ClosureIteration, CollectIteration, CollectNestedIteration, ExistsIteration, ForAllIteration, IsUniqueIteration, IterateIteration, OneIteration, OnlyIteration, RejectIteration, SelectIteration, SortedByIteration

public abstract class AbstractIteration
extends AbstractFeature
implements LibraryIteration.LibraryIterationExtension

AbstractIteration realizes shared characteristics of library iterations by providing a default iteration algorithm with a call-back at each iteration step.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	AbstractIteration.MutableObject A MutableObject may be used as an iteration accumulatior containing a single changing value.

Nested classes/interfaces inherited from interface org.eclipse.ocl.pivot.library.LibraryIteration

LibraryIteration.LibraryIterationExtension

Field Summary

Fields

Modifier and Type	Field and Description
protected static java.lang.Object	CARRY_ON An out-of-band value that can be returned by updateAccumulator(org.eclipse.ocl.pivot.evaluation.IterationManager) to signal that the iteration should carry on rather than terminate using the returned value.

Fields inherited from class org.eclipse.ocl.pivot.utilities.ValueUtil

EMPTY_BAG, EMPTY_SET, FALSE_VALUE, INTEGER_MAX_VALUE, INTEGER_MIN_VALUE, INVALID_VALUE, LONG_MAX_VALUE, LONG_MIN_VALUE, NULL_STRING, NULL_VALUE, ONE_VALUE, TRUE_VALUE, UNLIMITED_ONE_VALUE, UNLIMITED_VALUE, ZERO_VALUE

Constructor Summary

Constructors

Constructor and Description
AbstractIteration()

Method Summary

Modifier and Type	Method and Description
java.lang.Object	evaluateIteration(IterationManager iterationManager) The default iteration algorithm steps through the iteration domain by invoking IterationManager.hasCurrent() and IterationManager.advanceIterators().
protected java.lang.Object	resolveTerminalValue(IterationManager iterationManager) Return the final result at the end of an iteration over all the source elements.
protected abstract java.lang.Object	updateAccumulator(IterationManager iterationManager) Update the accumulatorValue with the bodyValue resulting from the current iteration for which the iterators define the context in the environment.

Methods inherited from class org.eclipse.ocl.pivot.utilities.ValueUtil

asBagValue, asBoolean, asClass, asCollectionType, asCollectionValue, asInteger, asIntegerValue, asMapType, asMapValue, asNavigableObject, asNavigableObject, asObject, asOrderedCollectionValue, asOrderedSetValue, asRealValue, asSequenceValue, asSetValue, asString, asTupleValue, asType, asUniqueCollectionValue, asUnlimitedNaturalValue, asValue, bigDecimalValueOf, bigIntegerValueOf, byteValueOf, characterValueOf, computeCollectionHashCode, createBagAccumulatorValue, createBagOfEach, createBagRange, createBagValue, createCollectionAccumulatorValue, createInvalidValue, createMapEntry, createMapOfEach, createMapValue, createObjectValue, createOrderedSetAccumulatorValue, createOrderedSetOfEach, createOrderedSetRange, createOrderedSetValue, createRange, createSequenceAccumulatorValue, createSequenceOfEach, createSequenceRange, createSequenceRange, createSequenceValue, createSetAccumulatorValue, createSetOfEach, createSetRange, createSetValue, createTupleOfEach, createTupleValue, doubleValueOf, floatValueOf, getElementIdName, getExecutor, getTypeName, initAllStatics, integerValueOf, integerValueOf, integerValueOf, integerValueOf, integerValueOf, intValueOf, isBoxed, isCollectionValue, isEcore, isIntegerNumber, isIntegerValue, isRealNumber, isUnboxed, isUnlimited, longValueOf, numberValueOf, oclToString, realValueOf, realValueOf, realValueOf, realValueOf, realValueOf, shortValueOf, stringValueOf, throwBooleanInvalidValueException, throwInvalidValueException, throwUnsupportedCompareTo, toString, typedIterable, unlimitedNaturalValueOf, unlimitedNaturalValueOf, unlimitedNaturalValueOf, unlimitedNaturalValueOf, unlimitedNaturalValueOf

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.eclipse.ocl.pivot.library.LibraryIteration.LibraryIterationExtension

createAccumulatorValue

Methods inherited from interface org.eclipse.ocl.pivot.library.LibraryIteration

createAccumulatorValue

Field Detail

CARRY_ON

@NonNull
protected static final java.lang.Object CARRY_ON

An out-of-band value that can be returned by updateAccumulator(org.eclipse.ocl.pivot.evaluation.IterationManager) to signal that the iteration should carry on rather than terminate using the returned value.

Constructor Detail

AbstractIteration

public AbstractIteration()

Method Detail

evaluateIteration

@Nullable
public java.lang.Object evaluateIteration(@NonNull
                                                     IterationManager iterationManager)

The default iteration algorithm steps through the iteration domain by invoking IterationManager.hasCurrent() and IterationManager.advanceIterators(). At each step updateAccumulator(IterationManager) is invoked to update the accumulator for that step. A non-null return causes a premature exit and forms the return from the overall evaluation. If all steps complete resolveTerminalValue(IterationManager) is invoked to provide the return value.

Derived classes may override this method to change the iteration algorithm or override the call-backs to customize the default iteration.

Specified by:

evaluateIteration in interface LibraryIteration

Parameters:

iterationManager - the iteration space

Returns:

the result

resolveTerminalValue

@Nullable
protected java.lang.Object resolveTerminalValue(@NonNull
                                                           IterationManager iterationManager)

Return the final result at the end of an iteration over all the source elements. The default implementation just returns the accumulator. Derived iterations should override.
This method is bypassed if the iteration ends prematurely.

Parameters:

iterationManager - the iteration context

Returns:

the result

updateAccumulator

@Nullable
protected abstract java.lang.Object updateAccumulator(@NonNull
                                                                 IterationManager iterationManager)

Update the accumulatorValue with the bodyValue resulting from the current iteration for which the iterators define the context in the environment.

Parameters:

iterationManager - the iteration context

Returns:

non-CARRY_ON premature result of iteration, or CARRY_ON if complete