（三）springmvc之注解的基本使用

一、@Controller

• @Controller 标记一个类是Controller

二、RequestMapping  地址映射

• 2.1　　Value的操作。

                注解在类上面    （父）
                注解在方法上面。 (子)      

• 2.1.1 SpringMVC完整的请求，就是父子加请来的请求。

        <a href="<%=request.getContextPath()%>/userController/list">list方法</a>
        <a href="<%=request.getContextPath()%>/userController/save">save方法</a>

controller:

package com.controller;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;

@Controller
@RequestMapping(value = "/userController")
public class UserController {
    @RequestMapping(value = "/list")
    public ModelAndView list(HttpServletRequest request,
            HttpServletResponse response) throws Exception {

        System.out.println("r执行list方法");

        ModelAndView mv = new ModelAndView();
        mv.addObject("req_key", "Model Data");
        mv.setViewName("succ");
        return mv;
    }

    @RequestMapping(value = "/save")
    public ModelAndView save(HttpServletRequest request,
            HttpServletResponse response) throws Exception {

        System.out.println("r执行save方法");

        ModelAndView mv = new ModelAndView();
        mv.addObject("req_key", "Model Data");
        mv.setViewName("succ");
        return mv;
    }

}

•      2.2 　　用于映射请求中的参数。

        <a href="<%=request.getContextPath()%>/paramController?task=list">list方法</a>
        <a href="<%=request.getContextPath()%>/paramController?task=save">save方法</a>    

controller:

package com.controller;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;

@Controller
@RequestMapping(value = "/paramController")
public class ParamController {
    @RequestMapping(params = "task=list")
    public ModelAndView list(HttpServletRequest request,
            HttpServletResponse response) throws Exception {

        System.out.println("r执行list方法");

        ModelAndView mv = new ModelAndView();
        mv.addObject("req_key", "Model Data");
        mv.setViewName("succ");
        return mv;
    }

    @RequestMapping(params = "task=save")
    public ModelAndView save(HttpServletRequest request,
            HttpServletResponse response) throws Exception {

        System.out.println("r执行save方法");

        ModelAndView mv = new ModelAndView();
        mv.addObject("req_key", "Model Data");
        mv.setViewName("succ");
        return mv;
    }

}

• 　　2.3　　Method：表示是处理哪一种请求.GET/POST

     <a href="<%=request.getContextPath()%>/methodController/add">list方法</a>

        <form method="post" action="<%=request.getContextPath()%>/methodController/add">
            <input type="submit" value="提交"/>
        </form>

controller:

package com.controller;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.servlet.ModelAndView;

@Controller
@RequestMapping(value = "/methodController")
public class MethodController {

    @RequestMapping(value = "/add", method = RequestMethod.GET)
    public ModelAndView add(HttpServletRequest request,
            HttpServletResponse response) throws Exception {

        System.out.println("处理GET请求");

        ModelAndView mv = new ModelAndView();
        mv.addObject("req_key", "Model Data");
        mv.setViewName("succ");
        return mv;
    }

    @RequestMapping(value = "/add", method = RequestMethod.POST)
    // @RequestMapping(value = "/add", method = { RequestMethod.GET,
    // RequestMethod.POST })
    public ModelAndView save(HttpServletRequest request,
            HttpServletResponse response) throws Exception {

        System.out.println("处理POST请求");

        ModelAndView mv = new ModelAndView();
        mv.addObject("req_key", "Model Data");
        mv.setViewName("succ");
        return mv;
    }

}

• 　　2.4　　RequestParam:获取地址中的参数信息。

    <a href="<%=request.getContextPath()%>/requestParamController/edit?userid=1">list方法</a>
    <a href="<%=request.getContextPath()%>/requestParamController?task=edit&userid=2">list方法</a>

controller

package com.controller;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.servlet.ModelAndView;

@Controller
@RequestMapping(value = "/requestParamController")
public class RequestParamController {

    @RequestMapping(value = "/edit", method = RequestMethod.GET)
    public ModelAndView edit_1(
            @RequestParam(name = "userid", required = false) String id)
            throws Exception {

        System.out.println("userid = " + id);

        return null;
    }

    @RequestMapping(params = "task=edit", method = RequestMethod.GET)
    public ModelAndView edit_2(String userid) throws Exception {

        System.out.println("task=edit中的userid = " + userid);

        return null;
    }

}

• 　　2.5　　PathVariable：REST风格.

    <a href="<%=request.getContextPath()%>/pathVarController/edit/1/admin">edit方法</a>
    <a href="<%=request.getContextPath()%>/pathVarController/edit/2/guest">edit方法</a>
    <a href="<%=request.getContextPath()%>/pathVarController/edit/3/test">edit方法</a>


<a href="<%=request.getContextPath()%>/pathVarController/3/admin/delete">通配符一个方法</a>
<a href="<%=request.getContextPath()%>/pathVarController/3/admin/test/xxxx/yyyy/remove">通配符多个方法</a>

　　controller

package com.controller;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.servlet.ModelAndView;

@Controller
@RequestMapping(value = "/pathVarController")
public class PathVarController {

    @RequestMapping(value = "/edit/{userid}/{username}", method = RequestMethod.GET)
    public ModelAndView edit_1(@PathVariable(value = "userid") String userid,
            @PathVariable(value = "username") String username) throws Exception {

        System.out.println("userid = " + userid);
        System.out.println("username = " + username);

        return null;
    }

    /**
     * 通配符的写法
     * 
     * 1个*代表通配一个地址
     * 
     * 2个*代表通配多个地址
     */
    @RequestMapping(value = "{userid}/*/delete", method = RequestMethod.GET)
    public ModelAndView delete_1(@PathVariable(value = "userid") String userid)
            throws Exception {

        System.out.println("delete_1====>userid = " + userid);

        return null;
    }

    @RequestMapping(value = "{userid}/**/remove", method = RequestMethod.GET)
    public ModelAndView delete_2(@PathVariable(value = "userid") String userid)
            throws Exception {

        System.out.println("remove_2====>userid = " + userid);

        return null;
    }
}

　　2.6　　header和cookie 

<a href="<%=request.getContextPath()%>/headerController/header">header</a>
    
<a href="<%=request.getContextPath()%>/headerController/cookie">cookie</a>

controller

package com.shyroke.controller;

import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.CookieValue;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestHeader;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.servlet.ModelAndView;

@Controller
@RequestMapping(value = "/headerController")
public class HeaderController {

    @RequestMapping(value = "/header", method = RequestMethod.GET)
    public ModelAndView header(@RequestHeader(name = "Host") String Host,
            @RequestHeader(name = "User-Agent") String agent,

            HttpServletRequest request, HttpServletResponse response)
            throws Exception {
        System.out.println("header");
        System.out.println("Host= " + Host);
        System.out.println("agent= " + agent);

        System.out.println("RequestHeader = " + request.getHeader("Host"));

        Cookie cookie_a = new Cookie("cookie_a", "Admin/GTUeST/axxxx");

        cookie_a.setPath("/");
        response.addCookie(cookie_a);
        return null;
    }

    @RequestMapping(value = "/cookie", method = RequestMethod.GET)
    public ModelAndView cookie(
            @CookieValue(name = "JSESSIONID", required = false) String sessionID,
            @CookieValue(name = "cookie_a", required = false) String cookie_a)
            throws Exception {
        System.out.println("cookie_1 = " + sessionID);

        System.out.println("cookie_a = " + cookie_a);

        return null;
    }

}

结果