springMVC--(讲解2)结果跳转方式

#方式1：经过ModelAndView实现
设置ModelAndView对象，根据viewName和视图解析器跳转到指定的页面。
页面路径：视图解析器前缀+viewName+视图解析器后缀
ModelAndView设置以下

@RequestMapping(value="/hello",method= RequestMethod.GET)
	public ModelAndView hello(HttpServletRequest req,HttpServletResponse resp){
		ModelAndView mav = new ModelAndView();
		//封装要显示的视图中的数据
		mav.addObject("msg","hello springmvc");
		//视图名，该视图是/WEB-INF/jsp/hello.jsp
		mav.setViewName("hello");
		return mav;
	}

视图解析器以下

<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：经过ServletAPI实现，这个不须要配置视图解析器
经过HttpServletResponse来进行输出

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

#方式3：经过HttpServletResponse来实现重定向

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

#方式4：经过HttpServletRequest转发

@RequestMapping(value="/hello",method= RequestMethod.GET)
	public void hello(HttpServletRequest req,HttpServletResponse resp) throws IOException, ServletException{
		//HttpServletResponse输出
		//resp.getWriter().println("hello mvc");
		//HttpServletResponse重定向  
		//resp.sendRedirect("index.jsp");
		//HttpServletRequest转发
		req.setAttribute("msg", "显示内容");
		req.getRequestDispatcher("index.jsp").forward(req, resp);
	}

#方式5：经过springmvc实现重定向与转发(没有视图解析器)
重定向与转发的区别
地址栏里的地址没有改变的话，是转发；改变了则是重定向。

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

重定向

@RequestMapping(value="/hello",method= RequestMethod.GET)
	public String hello(HttpServletRequest req,HttpServletResponse resp) throws IOException, ServletException{
		//转发方式1
		//return "index.jsp";
		//转发方式2
		//return "forward:index.jsp";
		//重定向(地址栏会改变)
		return "redirect:index.jsp";
	}

#方式6：经过springmvc实现重定向与转发(有视图解析器)

@RequestMapping(value="/hello",method= RequestMethod.GET)
	public String hello(HttpServletRequest req,HttpServletResponse resp) throws IOException, ServletException{
		//转发方式1(有视图解析器)
		//return "hello";
		//重定向(注意：重定向是不须要使用视图解析器的)
		return "redirect:index.jsp";
	}