通過http.client解析url返回的數據時為什么中文變成了unicode碼

今天在解析json數據的時候得到了一堆這樣的數據：{"errNum":0,"errMsg":"success","retData":[{"title":"\u6536\u5e9f\u54c1\u5927\u53d4\u521a\u4e0a\u53f0\uff0c\u5c31\u60e8\u906d\u8bc4\u59d4\u706d\u706f\uff0c\u4f46\u63a5\u4e0b\u6765\u5168\u573a\u90fd\u9707\u60ca\u4e86\uff01","url":"http:\/\/toutiao.com\/group\/6263036756505920002\/","abstract":"\u8ba2\u9605\u6211\u83b7\u53d6\u66f4\u591a\u7cbe\u5f69\u5185\u5bb9\uff01","image_url":"http:\/\/p1.pstatp.com\/list\/2f90009a31a7ee8bb15"}]}

這是因為，為了更好的傳輸中文，json進行了Unicode編碼。

這樣一來，我們在解析json之前，就得要先將json數據中的Unicode編碼轉換為我們使用的中文；

一：http請求數據返回json中string字段包含unicode的轉碼

 

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

二、普通string含有unicode轉碼方法

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

三、說一下比較奇怪的方案，測試中無意發現的，暫時沒弄明白原理（有明白原理的大神，請告知一聲，謝謝）

我用HttpClent的post方式獲取的json數據，得到的是帶Unicode碼的數據，需要轉換成中文才行，但是轉換的時間感覺有點長，就用HttpURLConnection的get方式又試了一下，在不轉碼的情況下，經過gson解析后，竟然神奇的自動轉換成了中文：

簡直是太神奇了，而且需要的時間相對於HttpClient的post請求方式的請求和處理時間更短，所以，果斷換用HttpURLConnection的get方式了

①現在先貼一下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();
        }
    }

調用的GsonTools的方法：（之前的博文中有寫到過）

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然后貼一下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));
    }

調用的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("接收字符串數據成功\nServerData:"+serverDataString);
            }
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        return serverDataString;
    }

③調用的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("接收字符串數據成功\nServerData:"+serverDataString);
            }
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        return serverDataString;
    }

谷歌提供的HttpClient的通信和HttpURLConnection網絡通信的時間間隔我也做了比較，明顯，HttpURLConnection的請求時間更短，所以果斷使用HttpURLConnection的方式

四、java中本身就提供了對Unicode 的url進行解碼的方法了：

 

System.out.println(URLDecoder.decode("\u82f9\u679c", "utf-8"));  詳細介紹請查看全文：https://cnblogs.com/qianzf/