Question

我无法登录我的学校moodle网页并下载源代码，到目前为止，我能够收到它从未实际登录的登录页面，任何帮助将不胜感激我已经坚持这个问题几个星期了。下面的代码不是我自己的代码，而是我在网上找到的多个示例的修改版本。

import java.net.*;
import java.io.*;
import java.util.*;

public class LoginByHttpPost
{
    private static final String POST_CONTENT_TYPE = "application/x-www-form-urlencoded";     
    private static final String LOGIN_USER_NAME = "myusername";
    private static final String LOGIN_PASSWORD = "mypassword";
    private static final String LOGIN_DOMAIN = "students.ltu.edu.au";

    private static final String TARGET_URL = "https://www.latrobe.edu.au/lms/login/";
    private String page ="";

    public static void main (String args[])
    {
        LoginByHttpPost httpUrlBasicAuthentication = new LoginByHttpPost();
        httpUrlBasicAuthentication.httpPostLogin();
    }

    public void httpPostLogin ()
    {
        try
        {
            String urlEncodedContent = preparePostContent(LOGIN_USER_NAME, LOGIN_PASSWORD, LOGIN_DOMAIN);

            HttpURLConnection urlConnection = doHttpPost(TARGET_URL, urlEncodedContent);

            page = readResponse(urlConnection);

            System.out.println("Successfully made the HTPP POST.");
            System.out.println("Recevied response is: '/n" + page + "'");

        }
        catch(IOException ioException)
        {
            System.out.println("Problems encounterd.");
        }
    }


    private String preparePostContent(String loginUserName, String loginPassword, String loginDomain) throws UnsupportedEncodingException
    {
        String encodedLoginUserName = URLEncoder.encode(loginUserName, "UTF-8");
        String encodedLoginPassword = URLEncoder.encode(loginPassword, "UTF-8");
        String encodedLoginDomain = URLEncoder.encode(loginDomain, "UTF-8");

        String content = URLEncoder.encode("username=", "UTF-8") + encodedLoginUserName
             + URLEncoder.encode("&password=", "UTF-8") + encodedLoginPassword
             + URLEncoder.encode("&domain=", "UTF-8") + encodedLoginDomain
             + URLEncoder.encode("&Login=", "UTF-8") + URLEncoder.encode("Login", "UTF-8");

        return content;

    }


    public HttpURLConnection doHttpPost(String targetUrl, String content) throws IOException
    {
        DataOutputStream dataOutputStream = null;
        HttpURLConnection conn = null; 
        String cookieFirst = null;
        String cookieValue = null;
        String totalCookie = "";
        try
        {
            CookieManager manager = new CookieManager();
            manager.setCookiePolicy(CookiePolicy.ACCEPT_ALL);
            CookieHandler.setDefault(manager);


            URL url = new URL(targetUrl);
            conn = (HttpURLConnection)url.openConnection();

            conn.getContent();

            CookieStore cookiejar = manager.getCookieStore();
            List<HttpCookie> cookiesList = cookiejar.getCookies();
            for(HttpCookie cookiel: cookiesList)
            {
               totalCookie += cookiel+"; ";
            }
            totalCookie = totalCookie.substring(0, totalCookie.length()-1);
            System.out.println("Total Cookie: " + totalCookie);

        }
        catch(Exception e)
        {
           System.out.println("Something went wrong");
        }

         HttpURLConnection urlConnection = null;

      try{
            URL url = new URL(targetUrl);
            urlConnection = (HttpURLConnection)url.openConnection();
            urlConnection.setDoInput(true);

            urlConnection.setDoOutput(true);

            urlConnection.setUseCaches(true);

            urlConnection.setRequestProperty("Content-Type", POST_CONTENT_TYPE);

            urlConnection.setRequestProperty("Content-Length", Integer.toString(content.length()));

            urlConnection.setInstanceFollowRedirects(true);

            urlConnection.setRequestMethod("POST");

            urlConnection.setRequestProperty("Cookie", totalCookie);

            urlConnection.connect();


            dataOutputStream = new DataOutputStream(urlConnection.getOutputStream());

            dataOutputStream.writeBytes(content);
            dataOutputStream.flush();
            dataOutputStream.close();

        }
        catch(IOException ioException)
        {
            System.out.println("I/O problems while trying to do a HTTP post.");
            ioException.printStackTrace();

            if (dataOutputStream != null)
            {
                try
                {
                    dataOutputStream.close();
                }
                catch(Throwable ignore)
                {
                }
            }
            if (urlConnection != null)
            {
                urlConnection.disconnect();
            }

            throw ioException;
        }

            return urlConnection;

    }


    private String readResponse(HttpURLConnection urlConnection) throws IOException
    {

        BufferedReader bufferedReader = null;
        try
        {
            bufferedReader = new BufferedReader(new InputStreamReader(urlConnection.getInputStream()));
            String responeLine;

            StringBuilder response = new StringBuilder();

            while ((responeLine = bufferedReader.readLine()) != null)
            {
                response.append(responeLine + "\n");
            }

            return response.toString();
        }
        catch(IOException ioException)
        {
            System.out.println("Problems while reading the response");
            ioException.printStackTrace();
            throw ioException;

        }
        finally
        {
            if (bufferedReader != null)
            {
                try
                {
                    bufferedReader.close();
                }
                catch(Throwable ignore)
                {
                }
            }

        }
    }
}

Answer 1

要访问此网页并登录，您使用的是Web浏览器，而不是一系列telnet命令，因为它更容易，对吧？然后，作为程序员，执行相同操作并使用程序化Web浏览器，而不是使用Cookie和URL连接的一系列低级操作。它也会容易得多。

HtmlUnit是一个程序化的网络浏览器。 Getting started page的结尾显示了加载网页和提交表单的示例。 HtmlUnit将为您处理提交，cookie处理，编码等。

使用java登录并下载网页并存储cookie

1 个答案: