文章来源http://blog.csdn.net/chunqiuwei/article/details/19924821
最近开发的项目有个功能的需求如下:根据用户提供的外部链接(outter_url),在页面填写好查询条件(param)并向该url发起查询请求,查询返回的数据来动态生成html的table来显示数据,同时要求请求的方法是post请求。
在开发过程中用的是jquery的异步请求。问题出现了,网上搜了半天没有发现实现jquery跨域进行post请求的解决方案(貌似不支持),所以自己用java代码来发起post跨域请求
关于实现思路的几点说明:
1) 项目中用的是spring,所以这个请求是在spring某个controller的方法中实现的,为了方便说明问题该方法假设为(ajaxProxy)
2) 在jsp页面中通过jquery的ajax方法,发起一个请求,该请求的url映射到1)中所说的那个ajaxProxy方法,并把查询条件(param)一起传递到ajaxProxy方法.部分代码如下
- $.ajax({
- type : "GET",
-
- url : "<c:url value='/user/put/queryItems'/>",
-
- data : param,
- dataType : 'json',
- success : function(data) {
3) 在ajaxProxy方法中,用HttpURLConnection链接outter_url,并设置connection的请求方法为Post,并发送查询条件(param),该部分的代码实现如下:
- URL connect = new URL(outer_url);
-
- HttpURLConnection connection =(HttpURLConnection)connect.openConnection();
-
- Connection.setRequestMethod(“Post”);
-
-
-
- OutputStreamWriter out = new OutputStreamWriter(connection.getOutputStream());
-
- out.wirte(param);
-
- out.flush();
4) 接收数据并返回数据,jsp页面中ajax的success方法处理接收到的数据data,并把data返回就可以了,接收数据的代码如下
- StringBuffer data = new StringBuffer();
- BufferedReader reader = new BufferedReader(new InputStreamReader(connection.getInputStream(), "gb2312"));
- String line;
- while ((line = reader.readLine()) != null) {
- data.append(line);
- }
-
- return data;
综上所述,实现跨域post请求的java实现代码如下
- @RequestMapping("queryItems")
- public @ResponseBody
- String ajaxProxy(String name, String startTime, String endTime,
- String tag, Model m, HttpServletRequest req) throws UnsupportedEncodingException {
-
-
- JSONObject node = new JSONObject();
- try {
-
- JSONObject param = new JSONObject();
- param.put("type", "");
- param.put("typevalue", "");
-
- param.put("key", new String(name.toString().getBytes("utf-8"), "gbk"));
- param.put("start_time", startTime);
- param.put("end_time", endTime);
- param.put("tags", tag);
- node.put("param", param);
-
- JSONObject user = new JSONObject();
- user.put("userid", "123");
- node.put("user", user);
-
- JSONObject device = new JSONObject();
- device.put("dnum", "123");
- node.put("device", device);
-
- JSONObject developer = new JSONObject();
- developer.put("apikey", "******");
- developer.put("secretkey", "*****");
- node.put("developer", developer);
-
- node.put("action", action);
-
- } catch (JSONException e1) {
-
- e1.printStackTrace();
- }
-
-
- URL connect;
- StringBuffer data = new StringBuffer();
- try {
- connect = new URL("outter_url");
- HttpURLConnection connection = (HttpURLConnection)connect.openConnection();
- connection.setRequestMethod("POST");
- connection.setDoOutput(true);
-
- OutputStreamWriter paramout = new OutputStreamWriter(
- connection.getOutputStream(),"UTF-8");
- paramout.write(json);
- paramout.flush();
-
- BufferedReader reader = new BufferedReader(new InputStreamReader(
- connection.getInputStream(), "gb2312"));
- String line;
- while ((line = reader.readLine()) != null) {
- data.append(line);
- }
-
- paramout.close();
- reader.close();
- } catch (Exception e) {
-
- e.printStackTrace();
- }
- return data.toString();
-
- }