Springmvc：(四) 结果跳转方式

一、ModelAndView

1. 视图解析器

   <!-- 视图解析器 -->
   <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"
         id="internalResourceViewResolver">
       <!-- 前缀 -->
       <property name="prefix" value="/WEB-INF/jsp/" />
       <!-- 后缀 -->
       <property name="suffix" value=".jsp" />
   </bean>
   

   controller

   public class ControllerTest1 implements Controller {
   
       public ModelAndView handleRequest(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse) throws Exception {
           //返回一个模型视图对象
           ModelAndView mv = new ModelAndView();
           mv.addObject("msg","ControllerTest1");
           mv.setViewName("test");
           return mv;
       }
   }
   

二、ServletAPI

导入依赖
<dependency>
 <groupId>javax.servlet</groupId>
 <artifactId>javax.servlet-api</artifactId>
 <version>4.0.1</version>
</dependency>

通过设置ServletAPI,不需要设置视图解析器

1. 通过HttpServletResponse进行输出，重定向，转发

@Controller
public class ResultGo {

    @RequestMapping("/result/t1")
    public void test1(HttpServletRequest req, HttpServletResponse rsp) throws IOException {
        rsp.getWriter().println("Hello,Spring BY servlet API");
    }

    @RequestMapping("/result/t2")
    public void test2(HttpServletRequest req, HttpServletResponse rsp) throws IOException {
        rsp.sendRedirect("/index.jsp");
    }

    @RequestMapping("/result/t3")
    public void test3(HttpServletRequest req, HttpServletResponse rsp) throws Exception {
        //转发
        req.setAttribute("msg","/result/t3");
        req.getRequestDispatcher("/WEB-INF/jsp/test.jsp").forward(req,rsp);
    }

}

三、springmvc

通过springmvc来实现转发和重定向，

• 无需视图解析器

@Controller
public class ResultSpringMVC {
    @RequestMapping("/rsm/t1")
    public String test1(){
        //转发
        return "/index.jsp";
    }

    @RequestMapping("/rsm/t2")
    public String test2(){
        //转发二
        return "forward:/index.jsp";
    }

    @RequestMapping("/rsm/t3")
    public String test3(){
        //重定向
        return "redirect:/index.jsp";
    }
}

• 有视图解析器

  @Controller
  public class ResultSpringMVC2 {
      @RequestMapping("/rsm2/t1")
      public String test1(){
          //转发
          return "test";
      }
  
      @RequestMapping("/rsm2/t2")
      public String test2(){
          //重定向
          return "redirect:/index.jsp";
          //return "redirect:hello.do"; //hello.do为另一个请求/
      }
  
  }