// Copyright (c) 2003-2012, Jodd Team (jodd.org). All Rights Reserved.
package jodd.util.collection;
import java.util.LinkedList;
/**
* Simple Stack (LIFO) class.
*/
public class SimpleStack<E> {
private LinkedList<E> list = new LinkedList<E>();
/**
* Stack push.
*/
public void push(E o) {
list.addLast(o);
}
/**
* Stack pop.
*
* @return poped object from stack
*/
public E pop() {
if (list.isEmpty()) {
return null;
}
return list.removeLast();
}
public Object[] popAll() {
Object[] res = new Object[list.size()];
for (int i = 0; i < res.length; i++) {
res[i] = list.get(i);
}
list.clear();
return res;
}
/**
* Peek element from stack.
*
* @return peeked object
*/
public E peek() {
return list.getLast();
}
/**
* Is stack empty?
*
* @return true if stack is empty
*/
public boolean isEmpty() {
return list.isEmpty();
}
/**
* Returns stack size.
*
* @return stack size
*/
public int size() {
return list.size();
}
}
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