解決使用httpclient傳遞json資料亂碼的問題

阿新 • • 發佈：2021-01-24

今天用httpclient傳輸json資料，服務端接受資料中文亂碼，下面分別貼上修改前與修改後的程式碼以及原因分析

（1）修改前：

client端

 public String sendHttpPost(String httpUrl,String data) {
 
 // 建立post請求
 HttpPost httpPost = new HttpPost(httpUrl);
 StringEntity entity;
 try {
 entity = new StringEntity(data);
 entity.setContentEncoding("UTF-8");
 entity.setContentType("application/json");
 httpPost.setEntity(entity);
 } catch (UnsupportedEncodingException e) {
 // TODO Auto-generated catch block
 e.printStackTrace();
 }
 
 return sendHttpPost(httpPost);
 }

private String sendHttpPost(HttpPost httpPost) {
 
 CloseableHttpClient httpClient = null;
 CloseableHttpResponse response = null;
 HttpEntity entity = null;
 String responseContent = null;
 
 // 建立預設的httpclient例項
 httpClient = HttpClients.createDefault();
 httpPost.setConfig(requestConfig);
 httpPost.setHeader("Accept","aplication/json");
 httpPost.addHeader("Content-Type","application/json;charset=UTF-8");
 // 執行請求
 try {
 logger.info("開始同步資料");
 response = httpClient.execute(httpPost);
 entity = response.getEntity();
 responseContent = EntityUtils.toString(entity,"UTF-8");
 logger.info("資料同步結果：" + responseContent);
 } catch (IOException e) {
 logger.error("同步資料出錯：" + e.toString());
 e.printStackTrace();
 } finally {
 try {
 if (response != null) {
  response.close();
 }
 if (httpClient != null) {
  httpClient.close();
 }
 
 } catch (Exception e2) {
 logger.error("流關閉出錯：" + e2.toString());
 }
 
 }
 return responseContent;
 }

（2）修改後

client端

 public String sendHttpPost(String httpUrl,String data) {
 
 // 建立post請求
 HttpPost httpPost = new HttpPost(httpUrl);
 StringEntity entity;
 entity = new StringEntity(data,"UTF-8");
 entity.setContentType("application/json");
 //entity.setContentType(new BasicHeader(HTTP.CONTENT_TYPE,"application/json"));//用這個跟上面一行那個結果一樣，可以檢視原始碼
 httpPost.setEntity(entity);
 
 return sendHttpPost(httpPost);
 }
 
 private String sendHttpPost(HttpPost httpPost) {
 
 CloseableHttpClient httpClient = null;
 CloseableHttpResponse response = null;
 HttpEntity entity = null;
 String responseContent = null;
 
 // 建立預設的httpclient例項
 httpClient = HttpClients.createDefault();
 httpPost.setConfig(requestConfig);
 httpPost.setHeader("Accept","aplication/json");
 
 httpPost.addHeader("Content-Type","application/json;charset=UTF-8");
 }

服務端程式碼

 //服務端 程式碼 通過紅色字型的程式碼接受資料
 public Map<String,Object> getRequestPostParams(HttpServletRequest request) throws BusinessException {
 try {
 //接收資料
 StringBuffer sb = new StringBuffer() ;
 InputStream is = request.getInputStream(); 
 InputStreamReader isr = new InputStreamReader(is,"utf-8"); 
 BufferedReader br = new BufferedReader(isr); 
 String s = "" ; 
 while((s=br.readLine())!=null){ 
 
 sb.append(s) ; 
 } 
 String strData = sb.toString();
 
 if (null == strData || "".equals(strData)) {
 return new HashMap<String,Object>();
 }
 Map<String,Object> params = this.parseJSON2Map(strData);
 return params;
 
 } catch(Exception e) {
 throw new BusinessException(BusinessException.ERROR_INNER,"引數轉換錯誤！");
 }
 }

下面來解釋原因：

看到這裡發現了client端的不同的吧，沒錯只有一行程式碼不一樣

entity = new StringEntity(data,"UTF-8");

就是這行程式碼，因為構造方法的不同造成的

本來參考了這篇文章把問題解決了，但是我發現我自己的程式碼明明也設定額編碼為什麼會出現亂碼呢，於是我就去看原始碼的實現，差異在哪裡？下面貼上原始碼

public StringEntity(final String string,final ContentType contentType) throws UnsupportedCharsetException {
 
 super();
 Args.notNull(string,"Source string");
 Charset charset = contentType != null ? contentType.getCharset() : null;
 if (charset == null) {
  charset = HTTP.DEF_CONTENT_CHARSET;
 }
 try {
  this.content = string.getBytes(charset.name());
 } catch (final UnsupportedEncodingException ex) {
  // should never happen
  throw new UnsupportedCharsetException(charset.name());
 }
 if (contentType != null) {
  setContentType(contentType.toString());
 }
 
 }

然後就發現，在new StringEntity的時候，就已經將資料根據編碼進行了處理，也就是說，如果你呼叫 new StringEntity(String string)此構造方法，就會使用其預設的編碼進行轉碼（ISO-8859-1），無論你後面設定多少次（

entity.setContentEncoding("UTF-8");

或者

httpPost.addHeader("Content-Type","application/json;charset=UTF-8");

都不會改變字串已經被按轉碼變成Byte[]陣列的事實，當然在請求中設定傳輸編碼格式還是要做的。

其實說這麼多，解決問題的關鍵就一句話，在new StringEntity()的時候指定編碼就解決了，因為在new的同時已經做了字串的轉碼操作

之所以說這麼多，是想告訴自己，問題解決了固然是好，但應該知道為什麼這麼做，多看原始碼，多問自己為什麼，僅此共勉。

補充：httpclient post傳送json陣列並解決json亂碼問題

業務：

客戶端傳送json資料，服務端進行解析

client傳送json格式：

{"data":[{"name":"1;,a","id_no":"222,"cellphone":"123141a","abode_detail":"213,"emp_add":"werew3a","app_no":"111111111111a","create_time":"11a"},{"name":"張三","id_no":"null","cellphone":"null","abode_detail":"null","emp_add":"null","app_no":"null","create_time":"null"},{"name":"1;,","cellphone":"123141","emp_add":"werew3","app_no":"111111111111","create_time":"11"},ab","cellphone":"123141ab","emp_add":"werew3ab","app_no":"111111111111ab","create_time":"11ab"}],"sendtime":"20160503"}

廢話少說，直接上主要程式碼

client端

package msxf.until;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import msxf.until.model.People;
import org.apache.http.HttpStatus;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpUriRequest;
import org.apache.http.client.methods.RequestBuilder;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.DefaultHttpRequestRetryHandler;
import org.apache.http.impl.client.HttpClientBuilder;
import org.apache.http.message.BasicHeader;
import org.apache.http.protocol.HTTP;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
/**
 * Created by 小省.
 */
public class Main {
 private final static org.apache.log4j.Logger logger =org.apache.log4j.Logger.getLogger(Main.class);
 public static void main(String[] args) {
  Map ma=new HashMap();
  ma.put("sendtime","20160503");
  //連線impala查庫，返回List<People>，其中peopel為自定義實體類
  List<People> peopleList=ImpalaJdbc.connImpala();
  if(peopleList.size()==0){
   logger.info("peopleList.size()==0");
  }
  ma.put("data",peopleList);
  ObjectMapper om=new ObjectMapper();
  try {
   String jsonStr=om.writeValueAsString(ma);
   System.out.println(jsonStr);
   CloseableHttpResponse httpResponse=null;
   CloseableHttpClient httpClient= HttpClientBuilder.create().setRetryHandler(new DefaultHttpRequestRetryHandler()).build();
   //解決中文亂碼，注意與服務端同時存在
   StringEntity stringEntity=new StringEntity(jsonStr,"UTF-8");
  //就目前來說下面這段程式碼是可有可無 stringEntity.setContentEncoding(new BasicHeader(HTTP.CONTENT_TYPE,"application/json"));
  //post 地址
   HttpUriRequest httpUriRequest= RequestBuilder.post("http://localhost:8080/qc").setEntity(stringEntity).build();
  httpResponse=httpClient.execute(httpUriRequest);
   System.out.println("傳送");
   int statusCode=httpResponse.getStatusLine().getStatusCode();
   if(statusCode== HttpStatus.SC_OK){
//    HttpEntity entity = httpResponse.getEntity();
//    InputStream in =entity.getContent();
    System.out.println("檔案傳輸伺服器正常響應！");
   }
  } catch (JsonProcessingException e) {
   e.printStackTrace();
  } catch (UnsupportedEncodingException e) {
   e.printStackTrace();
  } catch (ClientProtocolException e) {
   e.printStackTrace();
  } catch (IOException e) {
   e.printStackTrace();
  }
 }
}

服務端

採用最原始的servlet

import org.apache.http.protocol.HTTP;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URLDecoder;
/**
 * Created by 小省.
 */
public class QcServlet extends javax.servlet.http.HttpServlet {
protected void doPost(javax.servlet.http.HttpServletRequest request,javax.servlet.http.HttpServletResponse response) throws javax.servlet.ServletException,IOException {
doGet(request,response);
}
protected void doGet(javax.servlet.http.HttpServletRequest request,IOException {
System.out.println("+++++++++++++++++++");
//解決中文亂碼
BufferedReader br =new BufferedReader(new InputStreamReader(request.getInputStream(),"UTF-8"));
String line=null;
StringBuffer sb =new StringBuffer();
while ((line=br.readLine())!=null){
sb.append(line);
}
System.out.println("sb.toString()"+sb.toString());
//就目前而言String reesult = URLDecoder.decode(sb.toString(),HTTP.UTF_8);是可有可無的，httpclient會自動解碼
//String reesult =sb.toString();
String reesult = URLDecoder.decode(sb.toString(),HTTP.UTF_8);
try {
//將string 字串轉化為json陣列，並且遍歷
JSONObject jsonObject =new JSONObject(reesult);
String mesage=(String) jsonObject.getString("data");
JSONArray myJsonArray = new JSONArray(mesage);
for(int i=0 ; i < myJsonArray.length() ;i++){
//獲取每一個JsonObject物件
JSONObject myjObject = myJsonArray.getJSONObject(i);
System.out.println(myjObject.getString("name"));
}
System.out.println(reesult);
} catch (JSONException e) {
e.printStackTrace();
}
}
}

以上為個人經驗，希望能給大家一個參考，也希望大家多多支援我們。如有錯誤或未考慮完全的地方，望不吝賜教。