com.sun.jts.pi

Class ArrayListStack

java.lang.Object

com.sun.jts.pi.ArrayListStack

public class ArrayListStack
extends Object

The ArrayListStack class represents a last-in-first-out (LIFO) stack of objects. It encapsulates class ArrayList with four operations that allow a list 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, and a method to test for whether the stack is empty

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

Version:

$Revision: 1.3 $ on $Date: 2005/12/25 04:12:09 $

Author:

Darpan Dinker, $Author: tcfujii $

Constructor Summary

Constructors

Constructor and Description
ArrayListStack() Creates a stack with a default size
ArrayListStack(int size) Creates a stack with the given initial size

Method Summary

Modifier and Type	Method and Description
boolean	empty() Tests if this stack is empty.
Object	peek() Looks at the object at the top of this stack without removing it from the stack.
Object	pop() Removes the object at the top of this stack and returns that object as the value of this function.
void	push(Object obj) Pushes an item onto the top of this stack.
int	size() Provides the current size of the stack.

Methods inherited from class java.lang.Object

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

Constructor Detail

ArrayListStack

public ArrayListStack(int size)

Creates a stack with the given initial size

ArrayListStack

public ArrayListStack()

Creates a stack with a default size

Method Detail

size

public int size()

Provides the current size of the stack.

Returns:

int return the current size.

push

public void push(Object obj)

Pushes an item onto the top of this stack. This method will internally add elements to the ArrayList if the stack is full.

Parameters:

obj - the object to be pushed onto this stack.

See Also:

ArrayList.add(E)

pop

public Object 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 ArrayList object). Null if stack is empty.

empty

public boolean empty()

Tests if this stack is empty.

Returns:

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

peek

public Object 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 ArrayList object). Null if stack is empty.