两种设计方式哪种更好一些?
结构:
Com.news.dao: NewsDAO
Com.news.dao.impl: NewsDAOImpl
Com.news.dto: News
Com.news.service : NewsService
Com.news.servlet: AddNews,DeleteNews.ModifyNews
public class NewsService
{
private NewsDao newsDAO=new NewsDAOImpl();
public boolean addNews(News news) {
…..
}
}
public class AddNewsServlet extends HttpServlet {
{
……
NewsService nservice = new NewsService();
}
另一种结构
Com.news.dao : NewsDAO
Com.news.impl : NewsDAOImpl
Com.news.dto : News
Com.news.action:Action(接口),AddNews, DeleteNews.ModifyNews
Com.news.servlet
这种方式在com.news.action中有一个接口及相应的动作
public interface Action
{
public execute(HttpServletRequest request, HttpServletResponse response) throws IOException,ServletException;
}
public class AddNews implements Action
{
Public execute(HttpServletRequest request, HttpServletResponse response) throws IOException,ServletException
{
……
}
}
在serlet的处理中是根据传进来的参数来选择动作
Dopost(…)
{
String action= request.getParameter(“action”);
Action a=null;
if(“add”.equals(action))
{
A=AddNews();
a. execute(..);
}
Else if()
{
…
}
}