微信公众号开发工具类整理

大家知道微信提供的api接口很多，所以发送get或者post请求的方法是必备的。

//post请求
    public static String sendPost(String param, String url) {
        PrintWriter out = null;
        BufferedReader in = null;
        String result = "";
        try {
            URL realUrl = new URL(url);
            // 打开和URL之间的连接
            URLConnection conn = realUrl.openConnection();
            // 设置通用的请求属性
            conn.setRequestProperty("accept", "*/*");
            conn.setRequestProperty("connection", "Keep-Alive");
            conn.setRequestProperty("user-agent",
                    "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
            // 发送POST请求必须设置如下两行
            conn.setDoOutput(true);
            conn.setDoInput(true);
            // 获取URLConnection对象对应的输出流
            // out = new PrintWriter(conn.getOutputStream());
            out = new PrintWriter(new OutputStreamWriter(
                    conn.getOutputStream(), "utf-8"));
            // 发送请求参数
            out.print(param);
            // flush输出流的缓冲
            out.flush();
            // 定义BufferedReader输入流来读取URL的响应
            in = new BufferedReader(new InputStreamReader(
                    conn.getInputStream(), "UTF-8"));
            String line;
            while ((line = in.readLine()) != null) {
                result += line;
            }
        } catch (Exception e) {
            System.out.println("发送 POST 请求出现异常！" + e);
            e.printStackTrace();
        }
        // 使用finally块来关闭输出流、输入流
        finally {
            try {
                if (out != null) {
                    out.close();
                }
                if (in != null) {
                    in.close();
                }
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }
        return result;
    }

/**
     * 接口调用 GET
     */
    public static String httpURLConectionGET(String geturl, SortedMap<String, String> params) {
        try {
            URL url = new URL(geturl);    // 把字符串转换为URL请求地址
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();// 打开连接

            connection.addRequestProperty("User-Agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0)");

            connection.connect();// 连接会话
            // 获取输入流
            BufferedReader br = new BufferedReader(new InputStreamReader(connection.getInputStream(), "UTF-8"));
            String line;
            StringBuilder sb = new StringBuilder();
            while ((line = br.readLine()) != null) {// 循环读取流
                sb.append(line);
            }
            br.close();// 关闭流
            connection.disconnect();// 断开连接
//            System.out.println(sb.toString());
            return sb.toString();
        } catch (Exception e) {
            e.printStackTrace();
            System.out.println("失败!");
        }
        return null;
    }

有时微信返回给我们是一个xml格式的数据，看起来不是很方便，转成Map格式会比较好。

//把xml信息转化为map
    public Map<String, String> parseXml(String xml) throws Exception {
        Map<String, String> map = new HashMap<String, String>();
        Document doc;
        try {
            doc = DocumentHelper.parseText(xml);
            Element el = doc.getRootElement();
            map = recGetXmlElementValue(el, map);
        } catch (DocumentException e) {
            e.printStackTrace();
        }
        return map;
    }

事件推送时接收的函数里的参数是request，这个时候需要从request里取出数据转成Map格式。

//把request信息转化为map
    public Map<String, String> parseXml(HttpServletRequest request) throws Exception {
        // 将解析结果存储在HashMap中
        Map<String, String> map = new HashMap<String, String>();

        // 从request中取得输入流
        InputStream inputStream = request.getInputStream();
        // 读取输入流
        SAXReader reader = new SAXReader();
        Document document = reader.read(inputStream);
        // 得到xml根元素
        Element root = document.getRootElement();
        // 得到根元素的所有子节点
        List<Element> elementList = root.elements();

        // 遍历所有子节点
        for (Element e : elementList) {
//            System.out.println(e.getName() + " = " + e.getText());
            map.put(e.getName(), e.getText());
        }

        // 释放资源
        inputStream.close();
        inputStream = null;
        return map;
    }