SpringMVC中@RequestParam 的使用

package com.day01springmvc.controller;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.servlet.ModelAndView;
 

@Controller
@RequestMapping("hello")
public class HelloController2 {
 
    /**
     * 接收普通請求參數
     * http://localhost:8080/hello/show16?name=linuxsir
     * url參數中的name必須要和@RequestParam("name")一致
     * @return
     */
    @RequestMapping("show16")
    public ModelAndView test16(@RequestParam("name")String name){
        ModelAndView mv = new ModelAndView();
        mv.setViewName("hello2");
        mv.addObject("msg", "接收普通的請求參數：" + name);
        return mv;
    }
 
    /**
     * 接收普通請求參數
     * http://localhost:8080/hello/show17
     * url中沒有name參數不會報錯、有就顯示出來
     * @return
     */
    @RequestMapping("show17")
    public ModelAndView test17(@RequestParam(value="name",required=false)String name){
        ModelAndView mv = new ModelAndView();
        mv.setViewName("hello2");
        mv.addObject("msg", "接收普通請求參數：" + name);
        return mv;
    }
 
    /**
     * 接收普通請求參數
     * http://localhost:8080/hello/show18?name=998 顯示為998
     * http://localhost:8080/hello/show18?name 顯示為hello
     * @return
     */
    @RequestMapping("show18")
    public ModelAndView test18(@RequestParam(value="name",required=true,defaultValue="hello")String name){
        ModelAndView mv = new ModelAndView();
        mv.setViewName("hello2");
        mv.addObject("msg", "接收普通請求參數：" + name);
        return mv;
    }
 
}