oop_crashkurs/SimpleActivityStack/src/solution/SimpleStack.java

package solution;

import java.util.LinkedList;
import java.util.List;

import testat.IAction;
import testat.ISimpleStack;

public class SimpleStack<T> implements ISimpleStack<T> {

	private List<T> list;

	public SimpleStack() {
		super();
		list = new LinkedList<T>();
	}

	@Override
	public int push(T t) {
		if (t != null) {
			if (list.contains(t)) {
				list.remove(t);
			}
			list.add(t);
			return list.size();
		}
		return 0;
	}

	@Override
	public T pop() {
		if (list.size() == 0) {
			return null;
		}
		return list.remove(list.size() - 1);
	}

	@Override
	public T remove(int i) {
		return list.remove(i);
	}

	@Override
	public int size() {
		return list.size();
	}

	@Override
	public boolean contains(Object o) {
		return list.contains(o);
	}

	@Override
	public T get(int i) {
		return list.get(i);
	}

	@Override
	public void forAll(IAction<T> action) {
		if (action != null) {
			list.forEach(t -> action.execute(t));
		}
	}
}