在用HttpUrlConnection请求极光推送restful时

涉及到一个参数序列化问题,对方要求

HTTP Post 的Content-Type 需采用 application/x-www-form-urlencoded


然后序列化时用了json(Map.tostring)导致对方的服务器没有接收到参数,于是改成 后者,

代码参数做了调整



private static String json2String(JSONObject json) throws UnsupportedEncodingException {
Iterator<String> sIterator = json.keys();
String urlpara = "";
while (sIterator.hasNext()) {
String key = sIterator.next();
//根据键获得值,值也可以是JSONObject,JSONArray,使用对应的参数接收即可
String value = json.getString(key);

urlpara += key + "=" + URLEncoder.encode(value, "UTF-8") + "&";
}

return urlpara;
}

done






package wzq.j2se;

import java.io.BufferedReader;

import java.io.DataOutputStream;

import java.io.IOException;

import java.io.InputStreamReader;

import java.net.HttpURLConnection;

import java.net.URL;

import java.net.URLEncoder;

public class HttpURLConnectionPost {

 /**

  * @param args

  * @throws IOException 

  */

 public static void main(String[] args) throws IOException {

  readContentFromPost();

 }

 public static void readContentFromPost() throws IOException {

        // Post请求的url,与get不同的是不需要带参数

        URL postUrl = new URL("​​​​");

        // 打开连接

        HttpURLConnection connection = (HttpURLConnection) postUrl.openConnection();


        // 设置是否向connection输出,因为这个是post请求,参数要放在

        // http正文内,因此需要设为true

        connection.setDoOutput(true);

        // Read from the connection. Default is true.

        connection.setDoInput(true);

        // 默认是 GET方式

        connection.setRequestMethod("POST");


        // Post 请求不能使用缓存

        connection.setUseCaches(false);


        connection.setInstanceFollowRedirects(true);


        // 配置本次连接的Content-type,配置为application/x-www-form-urlencoded的

        // 意思是正文是urlencoded编码过的form参数,下面我们可以看到我们对正文内容使用URLEncoder.encode

        // 进行编码

        connection.setRequestProperty("Content-Type","application/x-www-form-urlencoded");

        // 连接,从postUrl.openConnection()至此的配置必须要在connect之前完成,

        // 要注意的是connection.getOutputStream会隐含的进行connect。

        connection.connect();

        DataOutputStream out = new DataOutputStream(connection

                .getOutputStream());

        // The URL-encoded contend

        // 正文,正文内容其实跟get的URL中 '? '后的参数字符串一致

        String content = "account=" + URLEncoder.encode("一个大肥人", "UTF-8");

        content +="&pswd="+URLEncoder.encode("两个个大肥人", "UTF-8");;

        // DataOutputStream.writeBytes将字符串中的16位的unicode字符以8位的字符形式写到流里面

        out.writeBytes(content);

        out.flush();

        out.close(); 


        BufferedReader reader = new BufferedReader(new InputStreamReader(connection.getInputStream()));

        String line;


        while ((line = reader.readLine()) != null){

            System.out.println(line);

        }


        reader.close();

        connection.disconnect();

}

}


在接收端,这样获取参数:

String name = request.getParameter("account");

String pswd = request.getParameter("pswd");


 System.out.println(new String(name.getBytes("iso-8859-1"),"UTF-8")); 

 System.out.println(new String(pswd.getBytes("iso-8859-1"),"UTF-8"));



(二)




application/x-www-form-urlencoded

提交请求示例

curl -X POST 'http://localhost:8080/formPost' -d 'id=1&name=foo&mobile=13612345678'

wireshark抓包结果



对应的服务端解析参数源码

//org.springframework.web.method.annotation.RequestParamMethodArgumentResolver#resolveName
if (arg == null) {
String[] paramValues = webRequest.getParameterValues(name);
if (paramValues != null) {
arg = paramValues.length == 1 ? paramValues[0] : paramValues;
}
}

application/json

提交请求示例

curl -X POST -H "Content-Type: application/json" 'http://localhost:8080/jsonPost' -d '{"id":2,"name":"foo","mobile":"13656635451"}'

wireshark抓包结果


对应的服务端解析参数源码

//com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter#readInternal
protected Object readInternal(Class<? extends Object> clazz, HttpInputMessage inputMessage) throws IOException, HttpMessageNotReadableException {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
InputStream in = inputMessage.getBody();
byte[] buf = new byte[1024];

while(true) {
int bytes = in.read(buf);
if(bytes == -1) {
byte[] bytes1 = baos.toByteArray();
return JSON.parseObject(bytes1, 0, bytes1.length, this.charset.newDecoder(), clazz, new Feature[0]);
}

if(bytes > 0) {
baos.write(buf, 0, bytes);
}
}
}

混用示例

web层代码

@RequestMapping(value="/mixPost", method=RequestMethod.POST )
public Result<Void> mixPostTest(@RequestBody @Valid Foo foo, @RequestParam Integer sex)

提交请求

curl -X POST -H "Content-Type: application/json" 'http://localhost:8080/mixPost?sex=1' -d '{"id":2,"name":"foo","mobile":"13656635451"}'

补充--如何定位对应的源码

找到post请求解析参数源码

@RequestMapping(value="/formPost", method=RequestMethod.POST )
public Result<Void> formPostTest(@RequestParam int id, @RequestParam String name, @RequestParam String mobile)

因为id是必填参数 如果请求参数中不含id的话 会报错 如下所示

org.springframework.web.bind.MissingServletRequestParameterException: Required int parameter 'id' is not present
at org.springframework.web.method.annotation.RequestParamMethodArgumentResolver.handleMissingValue(RequestParamMethodArgumentResolver.java:255)
at org.springframework.web.method.annotation.AbstractNamedValueMethodArgumentResolver.resolveArgument(AbstractNamedValueMethodArgumentResolver.java:95)
at org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument(HandlerMethodArgumentResolverComposite.java:79)
at org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues(InvocableHandlerMethod.java:157)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:124)

通过此方法可以快速定位到源码

找到json请求解析参数的源码

@RequestMapping(value="/jsonPost", method=RequestMethod.POST )
public Result<Void> jsonPostTest(@RequestBody @Valid Foo foo)

因为肯定要先构造一个空Foo对象 然后才能注入各属性值 所以在Foo的无参构造函数中加断点, 可以定位到json请求解析参数的源码