MIP-02-Tema-02-GenericStack

package net.forlornly;

import java.util.ArrayList;
import java.util.List;

class GenericStackImpl<T> {
    private List<T> list = new ArrayList<T>();

    public void push(T t) {
        list.add(t);
    }

    public T top() {
        return list.get(list.size() - 1);
    }

    public T pop() {
        T t = list.get(list.size() - 1);

        list.remove(list.size() - 1);

        return t;
    }

    public boolean isEmpty() {
        return list.size() == 0;
    }

    public void clear() {
        list.clear();
    }
}

public class GenericStack {

    /**
     * @param args
     */
    public static void main(String[] args) {
        GenericStackImpl<Integer> gsi = new GenericStackImpl<Integer>();

        System.out.println("isEmpty(): " + gsi.isEmpty());

        gsi.push(1);
        gsi.push(2);
        gsi.push(3);

        System.out.println("top(): " + gsi.top());

        System.out.println("isEmpty(): " + gsi.isEmpty());

        System.out.println("pop(): " + gsi.pop());
        System.out.println("pop(): " + gsi.pop());
        System.out.println("pop(): " + gsi.pop());

        System.out.println("isEmpty(): " + gsi.isEmpty());

        gsi.push(4);
        gsi.push(5);
        gsi.push(6);

        System.out.println("top(): " + gsi.top());

        System.out.println("isEmpty(): " + gsi.isEmpty());

        gsi.clear();

        System.out.println("isEmpty(): " + gsi.isEmpty());
    }
}