JSON数据请求乱码问题? 400 报错

JSON数据请求乱码问题? 400 报错

try {
StringBuffer buffer = new StringBuffer();
HttpPost   httpRequest=new HttpPost("http://192.168.1.100:8080/users/userinfos.html");
/*httpRequest.setHeader("Content-Type", "application/x-www-form-urlencoded; charset=utf-8");*/
/*httpRequest.addHeader("charset", HTTP.UTF_8); */
HttpClient httpClient = new DefaultHttpClient();
HttpParams params1 = httpClient.getParams();
HttpConnectionParams.setConnectionTimeout(params1, 1000);
HttpConnectionParams.setSoTimeout(params1, 5000);
Log.i("infor", "timeout");
HttpResponse response = httpClient.execute(httpRequest);
HttpEntity entity = response.getEntity();
if(response.getStatusLine().getStatusCode()==200){
if (entity != null) {
BufferedReader reader = new BufferedReader(new InputStreamReader(
entity.getContent()));
String line = null;
while ((line = reader.readLine()) != null) {
buffer.append(line);
}
}
}
//Log.e("shuchu",buffer.toString());
       return buffer.toString();
} catch (Exception e) {
Log.e("msg", "网络连接失败");
return result;
}

获取数据乱码，求大神解答