Question

我正在尝试创建http客户端以进行简单的服务测试。在服务器端代码中，通过解析请求来读取参数，如下所述。我想设置一些参数，以便字段具有这些参数

final FileItemFactory factory = new DiskFileItemFactory();
final ServletFileUpload upload = new ServletFileUpload(factory);
List<FileItem> fields = upload.parseRequest(request);

但我无法从http客户端设置参数，因此字段值始终为空。我正在尝试使用代码

try {
        CloseableHttpClient httpClient = HttpClients.createDefault();

        HttpPost httpPost = new HttpPost(url);
        httpPost.setHeader("Accept",
                "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8");
        httpPost.setHeader("Connection", "keep-alive");
        httpPost.setHeader("Content-Type",
                "multipart/form-data; boundary=----WebKitFormBoundaryv1eAhALrGwBQXRIp");
        httpPost.setHeader("Host", "localhost:8080");
        httpPost.setHeader(
                "User-Agent",
                "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/53.0.2785.101 Safari/537.36");

        List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
        nameValuePairs.add(new BasicNameValuePair("test", "red"));
        httpPost.setEntity(new UrlEncodedFormEntity(nameValuePairs));

        CloseableHttpResponse response = httpClient.execute(httpPost);
    } catch (Exception e) {

    }

如果我做错了，请建议。

Answer 1

这里addFormField（）方法可以帮到你。使用addFormField（），将在字段变量中接收参数集。

        public class MultipartUtility {
        private final String boundary;
        private static final String LINE_FEED = "\r\n";
        private HttpURLConnection httpConn;
        private String charset;
        private OutputStream outputStream;
        private PrintWriter writer;
        public MultipartUtility(String requestURL, String charset)
            throws IOException {
        this.charset = charset;

        // creates a unique boundary based on time stamp
        boundary = "===" + System.currentTimeMillis() + "===";

        URL url = new URL(requestURL);
        httpConn = (HttpURLConnection) url.openConnection();
        httpConn.setUseCaches(false);
        httpConn.setDoOutput(true); // indicates POST method
        httpConn.setDoInput(true);
        httpConn.setRequestProperty("Content-Type",
                "multipart/form-data; boundary=" + boundary);
        httpConn.setRequestProperty("User-Agent", "CodeJava Agent");
        httpConn.setRequestProperty("Test", "Bonjour");
        outputStream = httpConn.getOutputStream();
        writer = new PrintWriter(new OutputStreamWriter(outputStream, charset),
                true);
    }

    public void addFormField(String name, String value) {
        writer.append("--" + boundary).append(LINE_FEED);
        writer.append("Content-Disposition: form-data; name=\"" + name + "\"")
                .append(LINE_FEED);
        writer.append("Content-Type: text/plain; charset=" + charset).append(
                LINE_FEED);
        writer.append(LINE_FEED);
        writer.append(value).append(LINE_FEED);
        writer.flush();
    }


    public void addFilePart(String fieldName, File uploadFile)
            throws IOException {
        String fileName = uploadFile.getName();
        writer.append("--" + boundary).append(LINE_FEED);
        writer.append(
                "Content-Disposition: form-data; name=\"" + fieldName
                        + "\"; filename=\"" + fileName + "\"")
                .append(LINE_FEED);
        writer.append(
                "Content-Type: "
                        + URLConnection.guessContentTypeFromName(fileName))
                .append(LINE_FEED);
        writer.append("Content-Transfer-Encoding: binary").append(LINE_FEED);
        writer.append(LINE_FEED);
        writer.flush();

        FileInputStream inputStream = new FileInputStream(uploadFile);
        byte[] buffer = new byte[4096];
        int bytesRead = -1;
        while ((bytesRead = inputStream.read(buffer)) != -1) {
            outputStream.write(buffer, 0, bytesRead);
        }
        outputStream.flush();
        inputStream.close();

        writer.append(LINE_FEED);
        writer.flush();
    }

    public void addHeaderField(String name, String value) {
        writer.append(name + ": " + value).append(LINE_FEED);
        writer.flush();
    }

    public List<String> finish() throws IOException {
        List<String> response = new ArrayList<String>();

        writer.append(LINE_FEED).flush();
        writer.append("--" + boundary + "--").append(LINE_FEED);
        writer.close();

        // checks server's status code first
        int status = httpConn.getResponseCode();
        if (status == HttpURLConnection.HTTP_OK) {
            BufferedReader reader = new BufferedReader(new InputStreamReader(
                    httpConn.getInputStream()));
            String line = null;
            while ((line = reader.readLine()) != null) {
                response.add(line);
            }
            reader.close();
            httpConn.disconnect();
        } else {
            throw new IOException("Server returned non-OK status: " + status);
        }
        return response;
    }

     public static void main(String[] args) {
            String charset = "UTF-8";
            File uploadFile1 = new File(filename);
            String requestURL = url;

            try {
                MultipartUtility multipart = new MultipartUtility(requestURL, charset);

                multipart.addHeaderField("User-Agent", "CodeJava");
                multipart.addHeaderField("Test-Header", "Header-Value");

                multipart.addFormField("description", "Cool Pictures");
                multipart.addFormField("keywords", "Java,upload,Spring");

                multipart.addFilePart("fileUpload", uploadFile1);

                List<String> response = multipart.finish();

                System.out.println("SERVER REPLIED:");

                for (String line : response) {
                    System.out.println(line);
                }
            } catch (IOException ex) {
                System.err.println(ex);
            }
        }
}

无法使用httpclient向控制器发送参数

1 个答案: