kodkod.util.collections

Class ArrayStack<T>

java.lang.Object

kodkod.util.collections.Stack<T>

kodkod.util.collections.ArrayStack<T>

All Implemented Interfaces:

Iterable<T>

public class ArrayStack<T>
extends Stack<T>

A Stack implementation based on an array.

Author:

Emina Torlak

Constructor Summary

Constructors

Constructor and Description
ArrayStack() Constructs an empty stack with the inital capacity of 10.
ArrayStack(int initialCapacity)

Method Summary

Modifier and Type	Method and Description
boolean	empty() Returns true if the stack is empty; otherwise returns false.
void	ensureCapacity(int minCapacity) Increases the capacity of this ArrayStack, if necessary, to ensure that it can hold at least the number of elements specified by the minimum capacity argument.
Iterator<T>	iterator() Iterates over the items in this Stack, starting at the top of the stack and working its way down.
T	peek() Looks at the object at the top of this stack without removing it from the stack.
T	pop() Removes the object at the top of this stack and returns that object as the value of this function.
T	push(T item) Pushes an item onto the top of this stack and returns it.
int	search(Object o) Returns the 1-based position where an object is on this stack.
int	size() Returns the size of this stack.
void	trimToSize() Trims the capacity of this ArrayStack to be the stack's current size.

Methods inherited from class kodkod.util.collections.Stack

equals, hashCode, toString

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Detail

ArrayStack

public ArrayStack()

Constructs an empty stack with the inital capacity of 10.

Ensures:

no this.elems'

ArrayStack

public ArrayStack(int initialCapacity)

Method Detail

empty

public boolean empty()

Description copied from class: Stack

Returns true if the stack is empty; otherwise returns false.

Specified by:

empty in class Stack<T>

Returns:

no this.elems

See Also:

Stack.empty()

ensureCapacity

public void ensureCapacity(int minCapacity)

Increases the capacity of this ArrayStack, if necessary, to ensure that it can hold at least the number of elements specified by the minimum capacity argument.

iterator

public Iterator<T> iterator()

Iterates over the items in this Stack, starting at the top of the stack and working its way down.

Specified by:

iterator in interface Iterable<T>

Specified by:

iterator in class Stack<T>

Returns:

iterator over the elements in this stack.

See Also:

Stack.iterator()

peek

public T peek()

Description copied from class: Stack

Looks at the object at the top of this stack without removing it from the stack.

Specified by:

peek in class Stack<T>

Returns:

this.elems[0]

See Also:

Stack.peek()

pop

public T pop()

Description copied from class: Stack

Removes the object at the top of this stack and returns that object as the value of this function.

Specified by:

pop in class Stack<T>

Ensures:

this.size' = this.size - 1 && all i: [1..this.size) | this.elems'[i-1] = this.elems[i]

Returns:

this.elems[0]

See Also:

Stack.pop()

push

public T push(T item)

Pushes an item onto the top of this stack and returns it.

Specified by:

push in class Stack<T>

Ensures:

this.size' = this.size + 1 && this.elems'[0] = item && all i: [0..this.size) | this.elems'[i+1] = this.elems[i]

Returns:

item

See Also:

Stack.push(T)

search

public int search(Object o)

Description copied from class: Stack

Returns the 1-based position where an object is on this stack. If the object o occurs as an item in this stack, this method returns the distance from the top of the stack of the occurrence nearest the top of the stack; the topmost item on the stack is considered to be at distance 1. The equals method is used to compare o to the items in this stack.

Specified by:

search in class Stack<T>

Returns:

o in this.elems[int] => min(this.elems.o) + 1, -1

See Also:

Stack.search(java.lang.Object)

size

public int size()

Description copied from class: Stack

Returns the size of this stack.

Specified by:

size in class Stack<T>

Returns:

this.size

See Also:

Stack.size()

trimToSize

public void trimToSize()

Trims the capacity of this ArrayStack to be the stack's current size. An application can use this operation to minimize the storage of an ArrayStack instance.