Summary: Inherited Fields | Ctors | Methods | Inherited Methods | [Expand All]

public class

Stack

extends Vector<E>

java.lang.Object
↳	java.util.AbstractCollection<E>
	↳	java.util.AbstractList<E>
		↳	java.util.Vector<E>
			↳	java.util.Stack<T>

Class Overview

The Stack class represents a last-in-first-out (LIFO) stack of objects. It extends class Vector with five operations that allow a vector to be treated as a stack. The usual push and pop operations are provided, as well as a method to peek at the top item on the stack, a method to test for whether the stack is empty, and a method to search the stack for an item and discover how far it is from the top.

When a stack is first created, it contains no items.

Summary

[Expand]

Inherited Fields

From class java.util.Vector

From class java.util.AbstractList

Public Constructors
	Stack() Creates an empty Stack.

Public Methods
boolean	empty() Tests if this stack is empty.
synchronized T	peek() Looks at the object at the top of this stack without removing it from the stack.
synchronized 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.
synchronized int	search(Object o) Returns the 1-based position where an object is on this stack.

[Expand]

Inherited Methods

From class java.util.Vector

synchronized void	addElement(E obj) Adds the specified component to the end of this vector, increasing its size by one.
int	capacity() Returns the current capacity of this vector.
boolean	contains(Object elem) Tests if the specified object is a component in this vector.
synchronized void	copyInto(Object[] anArray) Copies the components of this vector into the specified array.
synchronized E	elementAt(int index) Returns the component at the specified index.
synchronized Enumeration<E>	elements() Returns an enumeration of the components of this vector.
synchronized void	ensureCapacity(int minCapacity) Increases the capacity of this vector, if necessary, to ensure that it can hold at least the number of components specified by the minimum capacity argument.
synchronized E	firstElement() Returns the first component of this vector.
E	get(int index) Returns the element at the specified position in this Vector.
int	indexOf(Object elem) Searches for the first occurrence of the given argument, testing for equality using the `equals` method.
synchronized int	indexOf(Object elem, int index) Searches for the first occurrence of the given argument, beginning the search at `index`, and testing for equality using the `equals` method.
synchronized void	insertElementAt(E obj, int index) Inserts the specified object as a component in this vector at the specified `index`.
boolean	isEmpty() Tests if this vector has no components.
synchronized E	lastElement() Returns the last component of the vector.
int	lastIndexOf(Object elem) Returns the index of the last occurrence of the specified object in this vector.
synchronized int	lastIndexOf(Object elem, int index) Searches backwards for the specified object, starting from the specified index, and returns an index to it.
synchronized void	removeAllElements() Removes all components from this vector and sets its size to zero.
synchronized boolean	removeElement(Object obj) Removes the first occurrence of the argument from this vector.
synchronized void	removeElementAt(int index) Deletes the component at the specified index.
synchronized void	setElementAt(E obj, int index) Sets the component at the specified `index` of this vector to be the specified object.
synchronized void	setSize(int newSize) Sets the size of this vector.
int	size() Returns the number of components in this vector.
synchronized Object[]	toArray() Returns an array containing all of the elements in this Vector in the correct order.
synchronized String	toString() Returns a string representation of this vector.
synchronized void	trimToSize() Trims the capacity of this vector to be the vector's current size.

From class java.util.AbstractList

void	add(int location, E object) Inserts the specified object into this List at the specified location.
boolean	add(E object) Adds the specified object at the end of this List.
boolean	addAll(int location, Collection<? extends E> collection) Inserts the objects in the specified Collection at the specified location in this List.
void	clear() Removes all elements from this list, leaving it empty.
boolean	equals(Object object) Compares the specified object to this list and return true if they are equal.
abstract E	get(int location) Returns the element at the specified location in this list.
int	hashCode() Returns the hash code of this list.
int	indexOf(Object object) Searches this list for the specified object and returns the index of the first occurrence.
Iterator<E>	iterator() Returns an iterator on the elements of this list.
int	lastIndexOf(Object object) Searches this list for the specified object and returns the index of the last occurrence.
ListIterator<E>	listIterator(int location) Returns a list iterator on the elements of this list.
ListIterator<E>	listIterator() Returns a ListIterator on the elements of this list.
E	remove(int location) Removes the object at the specified location from this list.
void	removeRange(int start, int end) Removes the objects in the specified range from the start to the end index minus one.
E	set(int location, E object) Replaces the element at the specified location in this list with the specified object.
List<E>	subList(int start, int end) Returns a part of consecutive elements of this list as a view.
Object[]	toArray() Returns a new array containing all elements contained in this `ArrayList`.

From class java.util.AbstractCollection

boolean	add(E object) Attempts to add `object` to the contents of this `Collection` (optional).
boolean	addAll(Collection<? extends E> collection) Attempts to add all of the objects contained in `collection` to the contents of this `Collection` (optional).
void	clear() Removes all elements from this `Collection`, leaving it empty (optional).
boolean	contains(Object object) Tests whether this `Collection` contains the specified object.
boolean	containsAll(Collection<?> collection) Tests whether this `Collection` contains all objects contained in the specified `Collection`.
boolean	isEmpty() Returns if this `Collection` contains no elements.
abstract Iterator<E>	iterator() Returns an instance of `Iterator` that may be used to access the objects contained by this `Collection`.
boolean	remove(Object object) Removes one instance of the specified object from this `Collection` if one is contained (optional).
boolean	removeAll(Collection<?> collection) Removes all occurrences in this `Collection` of each object in the specified `Collection` (optional).
boolean	retainAll(Collection<?> collection) Removes all objects from this `Collection` that are not also found in the `Collection` passed (optional).
abstract int	size() Returns a count of how many objects this `Collection` contains.
Object[]	toArray() Returns a new array containing all elements contained in this `ArrayList`.
String	toString() Returns the string representation of this `Collection`.

From class java.lang.Object

boolean	equals(Object obj) Indicates whether some other object is "equal to" this one.
final Class<?>	getClass() Returns the runtime class of an object.
int	hashCode() Returns a hash code value for the object.
final void	notify() Wakes up a single thread that is waiting on this object's monitor.
final void	notifyAll() Wakes up all threads that are waiting on this object's monitor.
String	toString() Returns a string representation of the object.
final void	wait(long timeout, int nanos) Causes current thread to wait until another thread invokes the `notify()` method or the `notifyAll()` method for this object, or some other thread interrupts the current thread, or a certain amount of real time has elapsed.
final void	wait(long timeout) Causes current thread to wait until either another thread invokes the `notify()` method or the `notifyAll()` method for this object, or a specified amount of time has elapsed.
final void	wait() Causes current thread to wait until another thread invokes the `notify()` method or the `notifyAll()` method for this object.

From interface java.lang.Iterable

From interface java.util.Collection

abstract boolean	add(E object) Attempts to add `object` to the contents of this `Collection` (optional).
abstract boolean	addAll(Collection<? extends E> collection) Attempts to add all of the objects contained in `Collection` to the contents of this `Collection` (optional).
abstract void	clear() Removes all elements from this `Collection`, leaving it empty (optional).
abstract boolean	contains(Object object) Tests whether this `Collection` contains the specified object.
abstract boolean	containsAll(Collection<?> collection) Tests whether this `Collection` contains all objects contained in the specified `Collection`.
abstract boolean	equals(Object object) Compares the argument to the receiver, and returns true if they represent the same object using a class specific comparison.
abstract int	hashCode() Returns an integer hash code for the receiver.
abstract boolean	isEmpty() Returns if this `Collection` contains no elements.
abstract Iterator<E>	iterator() Returns an instance of `Iterator` that may be used to access the objects contained by this `Collection`.
abstract boolean	remove(Object object) Removes one instance of the specified object from this `Collection` if one is contained (optional).
abstract boolean	removeAll(Collection<?> collection) Removes all occurrences in this `Collection` of each object in the specified `Collection` (optional).
abstract boolean	retainAll(Collection<?> collection) Removes all objects from this `Collection` that are not also found in the `Collection` passed (optional).
abstract int	size() Returns a count of how many objects this `Collection` contains.
abstract <T> T[]	toArray(T[] a) Returns an array containing all of the elements in this collection; the runtime type of the returned array is that of the specified array.
abstract Object[]	toArray() Returns an array containing all of the elements in this collection.

From interface java.util.List

abstract boolean	add(E object) Adds the specified object at the end of this `List`.
abstract void	add(int location, E object) Inserts the specified object into this `List` at the specified location.
abstract boolean	addAll(Collection<? extends E> collection) Adds the objects in the specified collection to the end of this `List`.
abstract boolean	addAll(int location, Collection<? extends E> collection) Inserts the objects in the specified collection at the specified location in this `List`.
abstract void	clear() Removes all elements from this `List`, leaving it empty.
abstract boolean	contains(Object object) Tests whether this `List` contains the specified object.
abstract boolean	containsAll(Collection<?> collection) Tests whether this `List` contains all objects contained in the specified collection.
abstract boolean	equals(Object object) Compares the given object with the `List`, and returns true if they represent the same object using a class specific comparison.
abstract E	get(int location) Returns the element at the specified location in this `List`.
abstract int	hashCode() Returns the hash code for this `List`.
abstract int	indexOf(Object object) Searches this `List` for the specified object and returns the index of the first occurrence.
abstract boolean	isEmpty() Returns whether this `List` contains no elements.
abstract Iterator<E>	iterator() Returns an iterator on the elements of this `List`.
abstract int	lastIndexOf(Object object) Searches this `List` for the specified object and returns the index of the last occurrence.
abstract ListIterator<E>	listIterator(int location) Returns a list iterator on the elements of this `List`.
abstract ListIterator<E>	listIterator() Returns a `List` iterator on the elements of this `List`.
abstract E	remove(int location) Removes the object at the specified location from this `List`.
abstract boolean	remove(Object object) Removes the first occurrence of the specified object from this `List`.
abstract boolean	removeAll(Collection<?> collection) Removes all occurrences in this `List` of each object in the specified collection.
abstract boolean	retainAll(Collection<?> collection) Removes all objects from this `List` that are not contained in the specified collection.
abstract E	set(int location, E object) Replaces the element at the specified location in this `List` with the specified object.
abstract int	size() Returns the number of elements in this `List`.
abstract List<E>	subList(int start, int end) Returns a `List` of the specified portion of this `List` from the given start index to the end index minus one.
abstract Object[]	toArray() Returns an array containing all of the elements in this list in proper sequence (from first to last element).
abstract <T> T[]	toArray(T[] a) Returns an array containing all of the elements in this list in proper sequence (from first to last element); the runtime type of the returned array is that of the specified array.

Public Constructors

public Stack ()

Creates an empty Stack.

Public Methods

public boolean empty ()

Tests if this stack is empty.

Returns

true if and only if this stack contains no items; false otherwise.

public synchronized T peek ()

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

Returns

the object at the top of this stack (the last item of the Vector object).

Throws

EmptyStackException	if this stack is empty.

public synchronized T pop ()

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

Returns

The object at the top of this stack (the last item of the Vector object).

Throws

EmptyStackException	if this stack is empty.

public T push (T item)

Pushes an item onto the top of this stack. This has exactly the same effect as:

 addElement(item)

Parameters

item	the item to be pushed onto this stack.

Returns

the item argument.

public synchronized 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.

Parameters

o	the desired object.

Returns

the 1-based position from the top of the stack where the object is located; the return value -1 indicates that the object is not on the stack.

Interfaces

Classes

Exceptions

Stack

Class Overview

Summary

Public Constructors

public Stack ()

Public Methods

public boolean empty ()

Returns

public synchronized T peek ()

Returns

Throws

public synchronized T pop ()

Returns

Throws

public T push (T item)

Parameters

Returns

See Also

public synchronized int search (Object o)

Parameters

Returns