springMVC--(講解2)結果跳轉方式

#方式1：經過ModelAndView實現
設置ModelAndView對象，根據viewName和視圖解析器跳轉到指定的頁面。
頁面路徑：視圖解析器前綴+viewName+視圖解析器後綴
ModelAndView設置以下

@RequestMapping(value="/hello",method= RequestMethod.GET)
	public ModelAndView hello(HttpServletRequest req,HttpServletResponse resp){
		ModelAndView mav = new ModelAndView();
		//封裝要顯示的視圖中的數據
		mav.addObject("msg","hello springmvc");
		//視圖名，該視圖是/WEB-INF/jsp/hello.jsp
		mav.setViewName("hello");
		return mav;
	}

視圖解析器以下

<bean id="viewResolver"  class="org.springframework.web.servlet.view.UrlBasedViewResolver">
		<property name="viewClass" value="org.springframework.web.servlet.view.JstlView"></property>
		<property name="prefix" value="/WEB-INF/jsp/"></property>
		<property name="suffix" value=".jsp"></property>
	</bean>

#方式2：經過ServletAPI實現，這個不須要配置視圖解析器
經過HttpServletResponse來進行輸出

@RequestMapping(value="/hello",method= RequestMethod.GET)
	public void hello(HttpServletRequest req,HttpServletResponse resp) throws IOException{
		resp.getWriter().println("hello mvc");
	}

#方式3：經過HttpServletResponse來實現重定向

@RequestMapping(value="/hello",method= RequestMethod.GET)
	public void hello(HttpServletRequest req,HttpServletResponse resp) throws IOException{
		//HttpServletResponse輸出
		//resp.getWriter().println("hello mvc");
		//HttpServletResponse重定向  
		resp.sendRedirect("index.jsp");
	}

#方式4：經過HttpServletRequest轉發

@RequestMapping(value="/hello",method= RequestMethod.GET)
	public void hello(HttpServletRequest req,HttpServletResponse resp) throws IOException, ServletException{
		//HttpServletResponse輸出
		//resp.getWriter().println("hello mvc");
		//HttpServletResponse重定向  
		//resp.sendRedirect("index.jsp");
		//HttpServletRequest轉發
		req.setAttribute("msg", "顯示內容");
		req.getRequestDispatcher("index.jsp").forward(req, resp);
	}

#方式5：經過springmvc實現重定向與轉發(沒有視圖解析器)
重定向與轉發的區別
地址欄裏的地址沒有改變的話，是轉發；改變了則是重定向。

@RequestMapping(value="/hello",method= RequestMethod.GET)
	public String hello(HttpServletRequest req,HttpServletResponse resp) throws IOException, ServletException{
		//轉發方式1
		//return "index.jsp";
		//轉發方式2
		return "forward:index.jsp";
	}

重定向

@RequestMapping(value="/hello",method= RequestMethod.GET)
	public String hello(HttpServletRequest req,HttpServletResponse resp) throws IOException, ServletException{
		//轉發方式1
		//return "index.jsp";
		//轉發方式2
		//return "forward:index.jsp";
		//重定向(地址欄會改變)
		return "redirect:index.jsp";
	}

#方式6：經過springmvc實現重定向與轉發(有視圖解析器)

@RequestMapping(value="/hello",method= RequestMethod.GET)
	public String hello(HttpServletRequest req,HttpServletResponse resp) throws IOException, ServletException{
		//轉發方式1(有視圖解析器)
		//return "hello";
		//重定向(注意：重定向是不須要使用視圖解析器的)
		return "redirect:index.jsp";
	}