/*
* Copyright 2007 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
*/
package java.util;
/**
* Maintains a last-in, first-out collection of objects. <a
* href="http://java.sun.com/j2se/1.5.0/docs/api/java/util/Stack.html">[Sun
* docs]</a>
*
* @param <E> element type.
*/
public class Stack<E> extends Vector<E> {
@Override
public Object clone() {
Stack<E> s = new Stack<E>();
s.addAll(this);
return s;
}
public boolean empty() {
return isEmpty();
}
public E peek() {
int sz = size();
if (sz > 0) {
return get(sz - 1);
} else {
throw new EmptyStackException();
}
}
public E pop() {
int sz = size();
if (sz > 0) {
return remove(sz - 1);
} else {
throw new EmptyStackException();
}
}
public E push(E o) {
add(o);
return o;
}
public int search(Object o) {
int pos = lastIndexOf(o);
if (pos >= 0) {
return size() - pos;
}
return -1;
}
}