kodkod.util.collections

Class LinkedStack<T>

java.lang.Object

kodkod.util.collections.Stack<T>

kodkod.util.collections.LinkedStack<T>

All Implemented Interfaces:

Iterable<T>

public final class LinkedStack<T>
extends Stack<T>

A Stack implementation based on a singly linked list.

Author:

Emina Torlak

Constructor Summary

Constructors

Constructor and Description
LinkedStack() Constructs an empty stack.

Method Summary

Modifier and Type	Method and Description
boolean	empty() Returns true if the stack is empty; otherwise returns false.
Iterator<T>	iterator() Iterates over the items in this LinkedStack, 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.

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

LinkedStack

public LinkedStack()

Constructs an empty stack.

Ensures:

no this.elems'

Method Detail

empty

public boolean empty()

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

Specified by:

empty in class Stack<T>

Returns:

no this.elems

iterator

public Iterator<T> iterator()

Iterates over the items in this LinkedStack, 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.

peek

public T peek()

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]

Throws:

EmptyStackException - no this.elems

pop

public T pop()

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]

Throws:

EmptyStackException - no this.elems

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

search

public int search(Object o)

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

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()