1999-08-28 08:19:56 +00:00

116 lines
2.9 KiB
C++

/*
* (C) Copyright The MITRE Corporation 1999 All rights reserved.
*
* The contents of this file are subject to the Mozilla Public License
* Version 1.0 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* The program provided "as is" without any warranty express or
* implied, including the warranty of non-infringement and the implied
* warranties of merchantibility and fitness for a particular purpose.
* The Copyright owner will not be liable for any damages suffered by
* you as a result of using the Program. In no event will the Copyright
* owner be liable for any special, indirect or consequential damages or
* lost profits even if the Copyright owner has been advised of the
* possibility of their occurrence.
*
* Please see release.txt distributed with this file for more information.
*
*/
/**
* Stack
* @author <a href="mailto:kvisco@mitre.org">Keith Visco</a>
* <BR/>
* <PRE>
* Modifications:
* 19990806: Larry Fitzpatrick
* - in method #peek():
* - Changed ListItem::ListItem to List::ListItem
* </PRE>
**/
#include "Stack.h"
//-------------/
//- Stack.cpp -/
//-------------/
/**
* Creates a new Stack
**/
Stack::Stack() : List() {
} //-- Stack
/**
* Destructor for Stack, will not delete Object references
**/
Stack::~Stack() {
//-- the base destructor for List will do all clean up
}
/**
* Returns an iterator that will iterator over the Stack, from the topmost
* element to the bottom element.
* You will need to delete this Iterator when you are done
**/
StackIterator* Stack::iterator() {
StackIterator* iter = (StackIterator*)List::iterator();
iter->reverse();
return iter;
} //-- iterator
/**
* Returns the specified Object from the top of this Stack,
* without removing it from the stack.
* @return a pointer to the object that is the top of this Stack
**/
void* Stack::peek() {
void* obj = 0;
List::ListItem* item = getLastItem();
if ( item ) obj = item->objPtr;
return obj;
} //-- peek
/**
* Adds the specified Object to the top of this Stack.
* @param obj a pointer to the object that is to be added to the
* top of this Stack
**/
void Stack::push(void* obj) {
add(obj);
} //-- push
/**
* Removes and returns the specified Object from the top of this Stack.
* @return a pointer to the object that was the top of this Stack
**/
void* Stack::pop() {
void* obj = 0;
ListItem* item = getLastItem();
if ( item ) obj = item->objPtr;
item = remove(item);
item->objPtr = 0;
delete item;
return obj;
} //-- pop
/**
* Returns true if there are no objects in the Stack.
* @return true if there are no objects in the Stack.
**/
MBool Stack::empty() {
return (MBool) (getLength() == 0);
} //-- empty
/**
* Returns the number of elements in the Stack
* @return the number of elements in the Stack
**/
int Stack::size() {
return getLength();
} //-- size