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':'123456'}
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。