通过http.client解析url返回的数据时为什么中文变成了unicode码

今天在解析json数据的时候得到了一堆这样的数据：{"errNum":0,"errMsg":"success","retData":[{"title":"u6536u5e9fu54c1u5927u53d4u521au4e0au53f0uff0cu5c31u60e8u906du8bc4u59d4u706du706fuff0cu4f46u63a5u4e0bu6765u5168u573au90fdu9707u60cau4e86uff01","url":"http://toutiao.com/group/6263036756505920002/","abstract":"u8ba2u9605u6211u83b7u53d6u66f4u591au7cbeu5f69u5185u5bb9uff01","image_url":"http://p1.pstatp.com/list/2f90009a31a7ee8bb15"}]}

这是因为，为了更好的传输中文，json进行了Unicode编码。

这样一来，我们在解析json之前，就得要先将json数据中的Unicode编码转换为我们使用的中文；

一：http请求数据返回json中string字段包含unicode的转码

 

public static String decodeUnicode(String theString) {
        char aChar;
        int len = theString.length();
        StringBuffer outBuffer = new StringBuffer(len);
        for (int x = 0; x < len;) {
            aChar = theString.charAt(x++);
            if (aChar == '\') {
                aChar = theString.charAt(x++);
                if (aChar == 'u') {
                    // Read the xxxx
                    int value = 0;
                    for (int i = 0; i < 4; i++) {
                        aChar = theString.charAt(x++);
                        switch (aChar) {
                        case '0':
                        case '1':
                        case '2':
                        case '3':
                        case '4':
                        case '5':
                        case '6':
                        case '7':
                        case '8':
                        case '9':
                            value = (value << 4) + aChar - '0';
                            break;
                        case 'a':
                        case 'b':
                        case 'c':
                        case 'd':
                        case 'e':
                        case 'f':
                            value = (value << 4) + 10 + aChar - 'a';
                            break;
                        case 'A':
                        case 'B':
                        case 'C':
                        case 'D':
                        case 'E':
                        case 'F':
                            value = (value << 4) + 10 + aChar - 'A';
                            break;
                        default:
                            throw new IllegalArgumentException(
                                    "Malformed   \uxxxx   encoding.");
                        }

                    }
                    outBuffer.append((char) value);
                } else {
                    if (aChar == 't')
                        aChar = '	';
                    else if (aChar == 'r')
                        aChar = '
';
                    else if (aChar == 'n')
                        aChar = '
';
                    else if (aChar == 'f')
                        aChar = 'f';
                    outBuffer.append(aChar);
                }
            } else
                outBuffer.append(aChar);
        }
        return outBuffer.toString();
    }

二、普通string含有unicode转码方法

public static String reEncoding(String text, String newEncoding) {
               String str = null;
               try {
                       str = new String(text.getBytes(), newEncoding);
               } catch (UnsupportedEncodingException e) {
                       log.error("不支持的字符编码" + newEncoding);
                       throw new RuntimeException(e);
               }
               return str;
       }

三、说一下比较奇怪的方案，测试中无意发现的，暂时没弄明白原理（有明白原理的大神，请告知一声，谢谢）

我用HttpClent的post方式获取的json数据，得到的是带Unicode码的数据，需要转换成中文才行，但是转换的时间感觉有点长，就用HttpURLConnection的get方式又试了一下，在不转码的情况下，经过gson解析后，竟然神奇的自动转换成了中文：

简直是太神奇了，而且需要的时间相对于HttpClient的post请求方式的请求和处理时间更短，所以，果断换用HttpURLConnection的get方式了

①现在先贴一下HttpURLConnection的get的方式：

@Test
    public void test() {
        try {
            long start = System.currentTimeMillis();
            URL url = new URL("http://apis.baidu.com/songshuxiansheng/news/news");

            HttpURLConnection connection = (HttpURLConnection) url.openConnection();
                connection.addRequestProperty("apikey","0fc807e45a37ce264f45d169646f4a9e" );
                String dataString = new String(GsonTools.IsToByte(connection.getInputStream()),"utf-8");
                HeadlineJson newsJson = GsonTools.getObjectData(dataString, HeadlineJson.class);
                List<Headline>list = newsJson.getRetData();
                System.out.println(list.toString());
                long end = System.currentTimeMillis();

            System.out.println("timeGap:"+(end-start));
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

调用的GsonTools的方法：（之前的博文中有写到过）

public static <T> T getObjectData(String jsonString, Class<T> type) {

        T t = null;
        try {
            Gson gson = new Gson();
            t = gson.fromJson(jsonString, type);
        } catch (JsonSyntaxException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return t;
    }

②然后贴一下HttpClient的post方式：

@Test
    public void TestHeadLine() {
        long start = System.currentTimeMillis();
        List<NameValuePair> params = new ArrayList<NameValuePair>();
        String url = "http://apis.baidu.com/songshuxiansheng/news/news";
        String jsonString = HttpUtils.getBaiDuString2(url, params);
        HeadlineJson lineJson = GsonTools.getObjectData(jsonString, HeadlineJson.class);
        System.out.println(lineJson.toString());
        long end = System.currentTimeMillis();

        System.out.println("timeGap:"+(end-start));
    }

调用的HttpUtils的方法：

public static String getBaiDuString(String url,List<NameValuePair> params) {
        String serverDataString = null;
        HttpPost post = new HttpPost(url);
        try {
            post.setEntity(new UrlEncodedFormEntity(params, HTTP.UTF_8));
            post.addHeader("apikey", UrlUtils.BAIDU_API_KEY);
            HttpClient client = new DefaultHttpClient();
            HttpResponse response = client.execute(post);
            int code = response.getStatusLine().getStatusCode();
            System.out.println("StatusCode:" + code);

            if (code == 200) {
                serverDataString = decodeUnicode(EntityUtils.toString(response.getEntity()));
//              serverDataString = EntityUtils.toString(response.getEntity());

                System.out.println("接收字符串数据成功
ServerData:"+serverDataString);
            }
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        return serverDataString;
    }

③调用的HttpClient的get方式

public static String getBaiDuString2(String url,List<NameValuePair> params) {
        String serverDataString = null;
        HttpGet get = new HttpGet(url);
        try {get.addHeader("apikey", UrlUtils.BAIDU_API_KEY);
            HttpClient client = new DefaultHttpClient();
            HttpResponse response = client.execute(get);
            int code = response.getStatusLine().getStatusCode();
            System.out.println("StatusCode:" + code);

            if (code == 200) {
//              serverDataString = decodeUnicode(EntityUtils.toString(response.getEntity()));
                serverDataString = EntityUtils.toString(response.getEntity());

                System.out.println("接收字符串数据成功
ServerData:"+serverDataString);
            }
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        return serverDataString;
    }

谷歌提供的HttpClient的通信和HttpURLConnection网络通信的时间间隔我也做了比较，明显，HttpURLConnection的请求时间更短，所以果断使用HttpURLConnection的方式

四、java中本身就提供了对Unicode 的url进行解码的方法了：

System.out.println(URLDecoder.decode("u82f9u679c", "utf-8"));  详细介绍请查看全文：https://cnblogs.com/qianzf/