Java發送POST請求，參數為JSON格式，並接收返回JSON數據

原文地址：https://blog.csdn.net/qq_26975307/article/details/82713725

/**
     * 發送post請求
     * @param url  路徑
     * @param jsonObject  參數(json類型)
     * @param encoding 編碼格式
     * @return
     * @throws ParseException
     * @throws IOException
     */
    public static String send(String url, JSONObject jsonObject,String encoding) throws ParseException, IOException{
        String body = "";
 
        //創建httpclient對象
        CloseableHttpClient client = HttpClients.createDefault();
        //創建post方式請求對象
        HttpPost httpPost = new HttpPost(url);
 
        //裝填參數
        StringEntity s = new StringEntity(jsonObject.toString(), "utf-8");
        s.setContentEncoding(new BasicHeader(HTTP.CONTENT_TYPE,
                "application/json"));
        //設置參數到請求對象中
        httpPost.setEntity(s);
        System.out.println("請求地址："+url);
//        System.out.println("請求參數："+nvps.toString());
 
        //設置header信息
        //指定報文頭【Content-type】、【User-Agent】
//        httpPost.setHeader("Content-type", "application/x-www-form-urlencoded");
        httpPost.setHeader("Content-type", "application/json");
        httpPost.setHeader("User-Agent", "Mozilla/4.0 (compatible; MSIE 5.0; Windows NT; DigExt)");
 
        //執行請求操作，並拿到結果（同步阻塞）
        CloseableHttpResponse response = client.execute(httpPost);
        //獲取結果實體
        HttpEntity entity = response.getEntity();
        if (entity != null) {
            //按指定編碼轉換結果實體為String類型
            body = EntityUtils.toString(entity, encoding);
        }
        EntityUtils.consume(entity);
        //釋放鏈接
        response.close();
        return body;
    }