javaservlet处理四种常用api请求get，put，post，delete

　　一般在网站搭建中servlet只需处理post，get请求便足已。本篇注重使用javaweb编写restful风格api，在servlet中对四种常用请求进行处理。

　　在api中对于一个请求要做的通常是提取header参数，提取携带数据(post，put)。在这里已post为例来说明用法。

　　下面是发起的post请求，用python（很简单）写的，该请求既有自定义header参数Bearer，也有携带数据bodys里的内容

import json
import requests

taken='YWMtoWBEBAFOEeei0SdHniRB6QAAAAAAAAAAAAAAAAAAjwAU4R56atn3HZQyagAgMAAAFanGEFTABPGgAqPOaU00kjW851AIpsKCuT8jAG1PqHyBpY6y5vOgk1zg'
headers = {'Accept': 'application/json','Content-Type':'application/json','Authorization':'Bearer '+taken}
bodys={'username':'test5','password':''}
url='http://localhost:8080/xiaoyanAPI'
response=requests.post(url,data=json.dumps(bodys),headers=headers)
print response.text

　　下面是处理post请求代码

 protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
         //打印某一个header
         System.out.println(request.getHeader("Authorization"));
         System.out.println();
         //获取header参数名，并打印出内容
         Enumeration<String> s=request.getHeaderNames();
         String str;
         while((str=s.nextElement())!=null)
             System.out.println(request.getHeader(str));
         System.out.println();
         //获取post携带数据流
         String acceptjson;
         try {
             BufferedReader br = new BufferedReader(new InputStreamReader( (ServletInputStream) request.getInputStream(), "utf-8"));
                         StringBuffer sb = new StringBuffer("");
                         String temp;
                         while ((temp = br.readLine()) != null) {
                             sb.append(temp);
                         }
                         br.close();
                         acceptjson = sb.toString();
                         System.out.print(acceptjson);
                     } catch (Exception e) {
                         e.printStackTrace();
                     }
     }

　　其他三种请求处理方式类似。