com.nwawsoft.util.datastructures

Class Stack

java.lang.Object

com.nwawsoft.util.datastructures.Stack

public class Stack
extends java.lang.Object

Data structure for storing and handling data in FILO order (first in, last out).

Constructor Summary

Constructors

Constructor and Description
Stack() Creates an empty stack.

Method Summary

Modifier and Type	Method and Description
boolean	isEmpty() Returns whether the stack is empty.
void	pop() The upmost object is removed (popped) from the stack.
java.lang.Object	popAndTop() Removes (pops) the upmost object from the stack and returns the new upmost object.
void	push(java.lang.Object object) Puts (pushes) a new object on the top of the stack.
java.lang.Object	top() Returns the upmost object of the stack.
java.lang.Object	topAndPop() Removes (pops) the upmost object from the stack and returns it.

Methods inherited from class java.lang.Object

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

Constructor Detail

Stack

public Stack()

Creates an empty stack.

Method Detail

isEmpty

public boolean isEmpty()

Returns whether the stack is empty.

Returns:

true, if the stack is empty. Else false.

push

public void push(java.lang.Object object)

Puts (pushes) a new object on the top of the stack.

Parameters:

object - any object.

pop

public void pop()

The upmost object is removed (popped) from the stack. If the stack was empty, nothing happens.

top

public java.lang.Object top()

Returns the upmost object of the stack. Returns null if the stack is empty.

Returns:

the upmost object of the stack. null if empty.

popAndTop

public java.lang.Object popAndTop()

Removes (pops) the upmost object from the stack and returns the new upmost object.

Returns:

the upmost object of the stack after a pop.

topAndPop

public java.lang.Object topAndPop()

Removes (pops) the upmost object from the stack and returns it.

Returns:

the upmost object of the stack before the pop.