解决使用httpclient传递json数据乱码的问题

今天用httpclient传输json数据，服务端接受数据 中文乱码，下面分别贴上修改前与修改后的代码以及原因分析

（1）修改前：

client端

 public string sendhttppost(string httpurl, string data) {
 
 // 创建post请求
 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;
 
 // 创建默认的httpclient实例
 httpclient = httpclients.createdefault();
 httppost.setconfig(requestconfig);
 httppost.setheader("accept","aplication/json");
 httppost.addheader("content-type","application/json;charset=utf-8");
 // 执行请求
 try {
 logger.info("开始同步数据");
 response = httpclient.execute(httppost);
 entity = response.getentity();
 responsecontent = entityutils.tostring(entity, "utf-8");
 logger.info("数据同步结果：" + responsecontent);
 } catch (ioexception e) {
 logger.error("同步数据出错：" + e.tostring());
 e.printstacktrace();
 } finally {
 try {
 if (response != null) {
  response.close();
 }
 if (httpclient != null) {
  httpclient.close();
 }
 
 } catch (exception e2) {
 logger.error("流关闭出错：" + e2.tostring());
 }
 
 }
 return responsecontent;
 }

（2）修改后

client端

 public string sendhttppost(string httpurl, string data) {
 
 // 创建post请求
 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"));//用这个跟上面一行那个结果一样，可以查看源码
 httppost.setentity(entity);
 
 return sendhttppost(httppost);
 }
 
 private string sendhttppost(httppost httppost) {
 
 closeablehttpclient httpclient = null;
 closeablehttpresponse response = null;
 httpentity entity = null;
 string responsecontent = null;
 
 // 创建默认的httpclient实例
 httpclient = httpclients.createdefault();
 httppost.setconfig(requestconfig);
 httppost.setheader("accept","aplication/json");
 
 httppost.addheader("content-type","application/json;charset=utf-8");
 }

服务端 代码

 //服务端 代码 通过红色字体的代码接受数据
 public map<string, object> getrequestpostparams(httpservletrequest request) throws businessexception {
 try {
 //接收数据
 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, "参数转换错误！");
 }
 }

下面来解释原因：

看到这里 发现了client端的不同的吧，没错 只有一行代码不一样

entity = new stringentity(data,"utf-8");

就是这行代码，因为构造方法的不同造成的

本来参考了把问题解决了，但是我发现 我自己的代码明明也设置额编码 为什么会出现乱码呢，于是我就去看源代码的实现，差异在哪里？ 下面贴上源代码

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());
 }
 
 }

然后就发现，在new stringentity的时候，就已经将数据根据编码进行了处理，也就是说，如果你调用 new stringentity(string string)此构造方法，就会使用其默认的编码进行转码（iso-8859-1），无论你后面设置多少次（

entity.setcontentencoding("utf-8");

或者

httppost.addheader("content-type","application/json;charset=utf-8");

都不会改变字符串已经被按转码变成byte[]数组的事实，当然在请求中设定传输编码格式还是要做的。

其实说这么多 ，解决问题的关键就一句话，在new stringentity()的时候指定编码就解决了，因为在new的同时已经做了字符串的转码操作

之所以说这么多，是想告诉自己，问题解决了固然是好，但应该知道为什么这么做，多看源码，多问自己为什么，仅此共勉。

补充：httpclient post发送json数组并解决json乱码问题

业务：

客户端发送json数据，服务端进行解析

client发送json格式：

{"data":[{"name":"1;,a","id_no":"222,a","cellphone":"123141a","abode_detail":"213,a","emp_add":"werew3a","app_no":"111111111111a","create_time":"11a"},{"name":"张三","id_no":"null","cellphone":"null","abode_detail":"null","emp_add":"null","app_no":"null","create_time":"null"},{"name":"1;,","id_no":"222,","cellphone":"123141","abode_detail":"213,","emp_add":"werew3","app_no":"111111111111","create_time":"11"},{"name":"1;,ab","id_no":"222,ab","cellphone":"123141ab","abode_detail":"213,ab","emp_add":"werew3ab","app_no":"111111111111ab","create_time":"11ab"}],"sendtime":"20160503"}

废话少说，直接上主要代码

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");
  //连接impala查库，返回list<people>，其中peopel为自定义实体类
  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();
   //解决中文乱码，注意与服务端同时存在
   stringentity stringentity=new stringentity(jsonstr,"utf-8");
  //就目前来说下面这段代码是可有可无 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("发送");
   int statuscode=httpresponse.getstatusline().getstatuscode();
   if(statuscode== httpstatus.sc_ok){
//    httpentity entity = httpresponse.getentity();
//    inputstream in =entity.getcontent();
    system.out.println("文件传输服务器正常响应！");
   }
  } catch (jsonprocessingexception e) {
   e.printstacktrace();
  } catch (unsupportedencodingexception e) {
   e.printstacktrace();
  } catch (clientprotocolexception e) {
   e.printstacktrace();
  } catch (ioexception e) {
   e.printstacktrace();
  }
 }
}

服务端

采用最原始的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, javax.servlet.http.httpservletresponse response) throws javax.servlet.servletexception, ioexception {
system.out.println("+++++++++++++++++++");
//解决中文乱码
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);是可有可无的，httpclient会自动解码
//string reesult =sb.tostring();
string reesult = urldecoder.decode(sb.tostring(), http.utf_8);
try {
//将string 字符串转化为json数组，并且遍历
jsonobject jsonobject =new jsonobject(reesult);
string mesage=(string) jsonobject.getstring("data");
jsonarray myjsonarray = new jsonarray(mesage);
for(int i=0 ; i < myjsonarray.length() ;i++){
//获取每一个jsonobject对象
jsonobject myjobject = myjsonarray.getjsonobject(i);
system.out.println(myjobject.getstring("name"));
}
system.out.println(reesult);
} catch (jsonexception e) {
e.printstacktrace();
}
}
}

以上为个人经验，希望能给大家一个参考，也希望大家多多支持。如有错误或未考虑完全的地方，望不吝赐教。