Java SpringMVC重定向，带有来自HTTP POST的响应

我需要使用SpringMVC重定向到一个外部服务，使用一个包含已构建对象的POST

通过阅读，我了解到不可能通过SpringMVC重定向来完成POST请求，因此需要通过Java代码中的HTTP客户机完成POST请求，我可以通过一个示例（如找到的示例）来完成

我需要能够将浏览器重定向到POST请求的响应，但是我不知道如何使用SpringMVC来实现

控制器

@RequestMapping(method = RequestMethod.GET, value = "/handoff")
public HttpEntity dispatch(HttpServletRequest request,
  @RequestParam(value = "referralURL", required = false) String referralUrl) {

    String redirectURL = "http://desinationURL.com/post";

    HttpClientHelper httpHelper = new HttpClientHelper();
    HttpEntity entity = httpHelper.httpClientPost(redirectURL, null);

    // Redirect
    return entity;
}

HttpClientHelper.java

public HttpEntity httpClientPost(String url, List<NameValuePair> params) throws ClientProtocolException, IOException {

    HttpClient httpclient = HttpClients.createDefault();
    HttpPost httppost = new HttpPost(url);

    // Request parameters and other properties.
    if (params != null) {
        httppost.setEntity(new UrlEncodedFormEntity(params, Constants.UTF_8_ENCODING));
    }

    // Execute and get the response.
    HttpResponse response = httpclient.execute(httppost);
    HttpEntity entity = response.getEntity();

    return entity;

}

公共HttpEntity httpClientPost（字符串url，列表参数）抛出ClientProtocolException，IOException{ HttpClient HttpClient=HttpClients.createDefault（）； HttpPost HttpPost=新的HttpPost（url）； //请求参数和其他属性。 如果（参数！=null）{ setEntity（新的UrlEncodedFormEntity（参数，常量.UTF_8_编码））； } //执行并获得响应。 HttpResponse response=httpclient.execute（httppost）； HttpEntity=response.getEntity（）； 返回实体； }

---

我可以看到目标服务被POST请求成功命中，我需要从MCV控制器读取响应的输出作为返回值，因为它当前只返回404

使用sendRedirect而不是HttpClient，控制器方法如下所示

@RequestMapping(method = RequestMethod.GET, value = "/handoff")
public HttpEntity dispatch(HttpServletRequest request, HttpServletResponse response,
  @RequestParam(value = "referralURL", required = false) String referralUrl) {

    String redirectURL = "http://desinationURL.com/post";

    response.setStatus(HttpServletResponse.SC_TEMPORARY_REDIRECT);
    response.setHeader("Location", redirectURL);

    // Redirect
    return entity;
}

无法将浏览器重定向到POST请求的响应。您所能做的就是将调用结果发送回外部URL。或者以某种方式处理响应，然后转发到应用程序中的其他页面，该页面显示有关响应的一些信息

e、 g

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如果您对更复杂的解决方案感兴趣，您可以利用Zuul实现这一点，并让Zuul管理请求转发。在筛选链期间，您可以根据需要操纵请求。

我就是这样做的

    CloseableHttpClient httpClient = HttpClients.custom()
            .setRedirectStrategy(new LaxRedirectStrategy())
            .build();

    //this reads the input stream from POST
    ServletInputStream str = request.getInputStream();

    HttpPost httpPost = new HttpPost(path);
    HttpEntity postParams = new InputStreamEntity(str);
    httpPost.setEntity(postParams);

    HttpResponse httpResponse = null ;
    int responseCode = -1 ;
    StringBuffer response  = new StringBuffer();

    try {

        httpResponse = httpClient.execute(httpPost);

        responseCode = httpResponse.getStatusLine().getStatusCode();
        logger.info("POST Response Status::  {} for file {}  ", responseCode, request.getQueryString());

        //return httpResponse ;
        BufferedReader reader = new BufferedReader(new InputStreamReader(
                httpResponse.getEntity().getContent()));

        String inputLine;
        while ((inputLine = reader.readLine()) != null) {
            response.append(inputLine);
        }
        reader.close();

        logger.info(" Final Complete Response {}  " + response.toString());
        httpClient.close();

    } catch (Exception e) {

        logger.error("Exception ", e);

    } finally {

        IOUtils.closeQuietly(httpClient);

    }

    // Return the response back to caller
    return  new ResponseEntity<String>(response.toString(), HttpStatus.ACCEPTED);

CloseableHttpClient-httpClient=HttpClients.custom（）
.setRedirectStrategy（新的LaxRedirectStrategy（））
.build（）；
//这将从POST读取输入流
ServletInputStream str=request.getInputStream（）；
HttpPost HttpPost=新的HttpPost（路径）；
HttpEntity后参数=新输入流实体（str）；
httpPost.setEntity（后参数）；
HttpResponse HttpResponse=null；
int-responseCode=-1；
StringBuffer响应=新的StringBuffer（）；
试一试{
httpResponse=httpClient.execute（httpPost）；
responseCode=httpResponse.getStatusLine（）.getStatusCode（）；
info（“文件{}的响应后状态：{}”，响应代码，request.getQueryString（））；
//返回httpResponse；
BufferedReader reader=新的BufferedReader（新的InputStreamReader(
httpResponse.getEntity（）.getContent（））；
字符串输入线；
而（（inputLine=reader.readLine（））！=null）{
追加（inputLine）；
}
reader.close（）；
info（“最终完整响应{}”+响应.toString（））；
httpClient.close（）；
}捕获（例外e）{
错误（“异常”，e）；
}最后{
IOUtils.closeclient（httpClient）；
}
//将响应返回给调用者
返回新的ResponseEntity（response.toString（），HttpStatus.ACCEPTED）；

我已经包含了HttpServletResponse，并按照建议设置了状态和标题值，但是它没有重定向，仍然返回404。我是否需要更改返回响应的方法而不是HttpEntity？

    CloseableHttpClient httpClient = HttpClients.custom()
            .setRedirectStrategy(new LaxRedirectStrategy())
            .build();

    //this reads the input stream from POST
    ServletInputStream str = request.getInputStream();

    HttpPost httpPost = new HttpPost(path);
    HttpEntity postParams = new InputStreamEntity(str);
    httpPost.setEntity(postParams);

    HttpResponse httpResponse = null ;
    int responseCode = -1 ;
    StringBuffer response  = new StringBuffer();

    try {

        httpResponse = httpClient.execute(httpPost);

        responseCode = httpResponse.getStatusLine().getStatusCode();
        logger.info("POST Response Status::  {} for file {}  ", responseCode, request.getQueryString());

        //return httpResponse ;
        BufferedReader reader = new BufferedReader(new InputStreamReader(
                httpResponse.getEntity().getContent()));

        String inputLine;
        while ((inputLine = reader.readLine()) != null) {
            response.append(inputLine);
        }
        reader.close();

        logger.info(" Final Complete Response {}  " + response.toString());
        httpClient.close();

    } catch (Exception e) {

        logger.error("Exception ", e);

    } finally {

        IOUtils.closeQuietly(httpClient);

    }

    // Return the response back to caller
    return  new ResponseEntity<String>(response.toString(), HttpStatus.ACCEPTED);