http post 不是从代码工作而是从邮递员工作

Question

这是代码

public class PostRequestMain {

    private static String ReadFile(String path) {
        String entityBody = new String();
        FileReader file;
        try {
            file = new FileReader(path);
            try {
                entityBody = IOUtils.toString(file);
            } catch (IOException e) {
                e.printStackTrace();
            }
        } catch (FileNotFoundException e1) {
            e1.printStackTrace();
        }
        return entityBody;
    }

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        MultiValueMap<String, String> headers = new LinkedMultiValueMap<String, String>();
        Map map = new HashMap<String, String>();
        map.put("Content-Type", "text/plain");
        map.put("userName", "username");
        map.put("password", "pass");

        String payLoad = ReadFile("src/main/resources/SamplePayload.html");

        headers.setAll(map);
        HttpEntity<String> requestPayload = new HttpEntity<String>(payLoad,headers);
        String url = "http://domain/path";

        ResponseEntity<String> responseEntity = null;

        UriComponentsBuilder uriComponents = UriComponentsBuilder.fromHttpUrl(url)
                .queryParam("param1", "value1");

        try {
            responseEntity = new RestTemplate().postForEntity(uriComponents.build().encode().toUri(), requestPayload, String.class);
        } catch (HttpStatusCodeException ex) {
            System.out.println("Status code = " + ex.getStatusCode());
        }

        String entityResponse = responseEntity.getBody();
        System.out.println(entityResponse);
    }

}

当我运行上面的代码时，它给了我异常

线程“main”中的异常

org.springframework.web.client.ResourceAccessException: I/O error on POST request for "http://domain/path ":Connection reset; nested exception is java.net.SocketException: Connection reset
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:503)
    at org.springframework.web.client.RestTemplate.execute(RestTemplate.java:465)
    at org.springframework.web.client.RestTemplate.postForEntity(RestTemplate.java:342)
    at sprinthttp1.PostRequestMain.main(PostRequestMain.java:61)
Caused by: java.net.SocketException: Connection reset
    at java.net.SocketInputStream.read(SocketInputStream.java:209)
    at java.net.SocketInputStream.read(SocketInputStream.java:141)
    at java.io.BufferedInputStream.fill(BufferedInputStream.java:246)
    at java.io.BufferedInputStream.read1(BufferedInputStream.java:286)
    at java.io.BufferedInputStream.read(BufferedInputStream.java:345)
    at sun.net.www.http.HttpClient.parseHTTPHeader(HttpClient.java:704)
    at sun.net.www.http.HttpClient.parseHTTP(HttpClient.java:647)
    at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1536)
    at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1441)
    at java.net.HttpURLConnection.getResponseCode(HttpURLConnection.java:480)
    at org.springframework.http.client.SimpleClientHttpResponse.getRawStatusCode(SimpleClientHttpResponse.java:47)
    at org.springframework.http.client.AbstractClientHttpResponse.getStatusCode(AbstractClientHttpResponse.java:32)
    at org.springframework.web.client.DefaultResponseErrorHandler.getHttpStatusCode(DefaultResponseErrorHandler.java:55)
    at org.springframework.web.client.DefaultResponseErrorHandler.hasError(DefaultResponseErrorHandler.java:49)
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:489)
    ... 3 more

但是当我尝试使用 Postman 向相同的 URL 发出发布请求时，我得到了正确的结果。我尝试了不同的方式来发布请求，但每次都是同样的错误。任何想法可能是什么问题？

Answer 1

如果不查看拒绝连接的域的具体示例 - 很难确切地说出了什么问题。

但是，根据我的经验，我遇到了非常类似的问题，并且服务器经常阻止标头中包含“java”关键字的请求User-Agent，该请求默认来自您的代码（不完全是“java”，而是包含它的字符串） 。这样做是专门为了阻止各种机器人。

因此，我建议您添加User-Agent标头并将其设置为类似Mozilla/5.0或简单的内容Postman emulator，然后看看它是如何工作的。