de.caff.generics

Class SimpleStack<T>

java.lang.Object

de.caff.generics.Countable.Base<TT>

de.caff.generics.Indexable.Base<T>

de.caff.generics.SimpleStack<T>

All Implemented Interfaces:

Countable<T>, Indexable<T>, Sizeable, java.lang.Iterable<T>

public class SimpleStack<T>
extends Indexable.Base<T>

A slim last-in-first-out list (i.e. stack) implementation which is not synchronized. This should operate faster than Stack which is synchronized. In difference to the standard stack implementation this class does only provide the necessary mutation methods. It also provides all read-only methods of Indexable.

This class is not thread-safe, see FStack for a functional thread-safe implementation.

Since:

December 13, 2025

Author:

Rammi

Nested Class Summary

Nested classes/interfaces inherited from interface de.caff.generics.Indexable

Indexable.Base<TT>, Indexable.IndexableSpliterator<TElem>, Indexable.ListView<T>

Field Summary

Fields inherited from interface de.caff.generics.Indexable

EMPTY, EMPTY_INDEXABLE_STRING

Fields inherited from interface de.caff.generics.Sizeable

NULL

Constructor Summary

Constructors

Constructor and Description
SimpleStack() Create a stack.
SimpleStack(int initialSize) Create a stack with the given initial size.
SimpleStack(java.lang.Iterable<? extends T> initialElements) Create a stack with an initial set of elements.

Method Summary

Modifier and Type	Method and Description
java.util.List<T>	asList() Get a view of this indexable as an unmodifiable list.
void	clear() Clear this stack.
T	get(int index) Get the element at the given index.
boolean	isEmpty() Is this indexable empty?
T	peek() Peek at the top-most stack element.
T	peek(int index) Peek at deeper elements.
T	peekOrNull() Peek at the top-most stack element.
T	pop() Pop the stack.
void	push(T obj) Push the stack down, and put the given object to the top of the stack.
int	size() Get the size.
void	trim() Trim this stack to the given size.

Methods inherited from class de.caff.generics.Indexable.Base

asBase

Methods inherited from class de.caff.generics.Countable.Base

equals, hashCode, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface de.caff.generics.Indexable

addToArray, addToArray, addToCollection, asCollection, binarySearch, checkIndex, combine, compactCollector, compare, downCast, emptyIndexable, equal, fastCollector, findAll, findAllX, findFirst, findFirst, findFirst, findFirstX, findLast, findLast, findLast, findNext, findNext, findNext, findNextX, findPrevious, findPrevious, findPrevious, first, firstMatch, firstMatch, firstMatchX, forEachEntry, forEachEntryFragile, fromArray, fromCollection, fromCollection, fromCountable, fromCountable, fromEnumeration, fromEnumeration, fromIterable, fromIterable, fromIterable, fromIterable, fromIterator, fromList, fromOptional, frozenSpliterator, getMod, gyt, hash, headSet, indexedView, indexes, init, initByIndex, initFragile, intIndexes, isOrdered, isStrictlyOrdered, iterator, iterator, last, listIterator, mapArray, optional, ordered, reverse, rotated, singleton, spliterator, subSet, sybSet, tailSet, toString, view, view, viewArray, viewArray, viewAsBooleanIndexable, viewAsByteIndexable, viewAsCharIndexable, viewAsDict, viewAsDoubleIndexable, viewAsFloatIndexable, viewAsIntIndexable, viewAsLongIndexable, viewAsShortIndexable, viewByIndex, viewFragile, viewList, viewList, viewListN, viewListN, viewTuple, viewTuple, viewTuple, viewTuple, viewTuple, viewTuple, viewTuple, viewTuple, withAppendedItem, withCachedHash, withExchangedItemAt, withInsertedItemAt, withPrependedItem, withRemovedItemAt, withSwappedItemsAt

Methods inherited from interface de.caff.generics.Countable

addAllTo, combined, combined, containsEq, containsRef, downCast, empty, equal, equals, filtered, filteredToIndexable, filterToCountable, firstOrNull, foldLeft, forEachFragile, freeze, frozen, frozen, getAny, groupingBy, groupingBy, hasAll, hasAny, isSorted, isStrictlySorted, lastOrNull, mappingBy, mappingBy, optFirst, optLast, orderedCombination, parallelStream, parellelStream, sorted, stream, toArray, toArray, toDict, toDict, toDict, toList, toString, uniform, viewCollection, viewCollection, viewCollectionN, viewCollectionN, withExchangedItem

Methods inherited from interface java.lang.Iterable

forEach

Constructor Detail

SimpleStack

public SimpleStack()

Create a stack.

SimpleStack

public SimpleStack(int initialSize)

Create a stack with the given initial size.

Parameters:

initialSize - initial size of this stack

SimpleStack

public SimpleStack(@NotNull
                   java.lang.Iterable<? extends T> initialElements)

Create a stack with an initial set of elements.

Parameters:

initialElements - initial elements of the stack, pushed in order, so the last element of the iteration becomes the top-most stack element

Method Detail

get

public T get(int index)

Description copied from interface: Indexable

Get the element at the given index.

Parameters:

index - index between 0 and size() - 1

Returns:

element at the given index

size

public int size()

Description copied from interface: Sizeable

Get the size. Size is never negative.

Returns:

the size of this object, usually the number of contained elements, must not be negative

isEmpty

public boolean isEmpty()

Description copied from interface: Indexable

Is this indexable empty?

Returns:

true: there are no elements in this indexable
false: this indexable has elements

asList

@NotNull
public java.util.List<T> asList()

Description copied from interface: Indexable

Get a view of this indexable as an unmodifiable list. This is especially useful for conversion to standard collection classes, eg for adding all elements via Collection.addAll(Collection) (but have a look at Countable.addAllTo(Collection)).

Returns:

collection view

See Also:

Countable.toList()

pop

public T pop()

Pop the stack.

Returns:

the popped element

Throws:

java.lang.IndexOutOfBoundsException - if this LIFO is empty

peek

public T peek()

Peek at the top-most stack element.

Returns:

the top-most stack element

Throws:

java.lang.IndexOutOfBoundsException - if this LIFO is empty

See Also:

peek(int), peekOrNull()

peekOrNull

@Nullable
public T peekOrNull()

Peek at the top-most stack element. Return null if this stack is empty.

Returns:

the top-most stack element, or null

peek

public T peek(int index)

Peek at deeper elements.

Parameters:

index - index of the element from the top, with 0 giving the same result as peek()

Returns:

element at the given offset from the top

Throws:

java.lang.IndexOutOfBoundsException - if index is out of range

push

public void push(T obj)

Push the stack down, and put the given object to the top of the stack.

Parameters:

obj - object to be pushed

trim

public void trim()

Trim this stack to the given size. This may be useful after the stack was only temporarily filled with lots of elements.

clear

public void clear()

Clear this stack. It will be empty after this method is called.