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/*
 * Copyright 2016 Carlos Ballesteros Velasco
 *
 * 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;

public class Stack extends Vector {
    public Stack() {
    }

    public E push(E item) {
        addElement(item);
        return item;
    }

    public synchronized E pop() {
        E obj;
        int len = size();
        obj = peek();
        removeElementAt(len - 1);
        return obj;
    }

    public synchronized E peek() {
        int len = size();
        if (len == 0) throw new EmptyStackException();
        return elementAt(len - 1);
    }

    public boolean empty() {
        return size() == 0;
    }

    public synchronized int search(Object o) {
        int i = lastIndexOf(o);
        if (i >= 0) return size() - i;
        return -1;
    }
}