LinkedStack

package first;
import java.util.LinkedList;
public class LinkedList {
	public class LinkedStack implements Stack {
		private LinkedList<Object> list = new LinkedList<Object>();
		@Override
		public Object pop() {
			// TODO Auto-generated method stub
			if (isEmpty()) {
				return null;
			}else {
				return list.removeFirst();
			}
		}

		@Override
		public Object peek() {
			// TODO Auto-generated method stub
			if(isEmpty()) {
				return null;
			}else {
				return list.getFirst();
			}
		}

		@Override
		public void push(Object e) {
			// TODO Auto-generated method stub
			list.addFirst(e);
		}

		@Override
		public void clear() {
			// TODO Auto-generated method stub
			list.clear();
		}

		@Override
		public int size() {
			// TODO Auto-generated method stub
			return list.size();
		}

		@Override
		public boolean isEmpty() {
			// TODO Auto-generated method stub
			return list.isEmpty();
		}
	}

}
}