如何使用 Java 代码登录 Facebook？

How to login Facebook using Java code?

提问by lingadurai.c

Possible Duplicate:
How to log into Facebook programmatically using Java?

可能的重复：
如何使用 Java 以编程方式登录 Facebook？

package facebook;

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

public class LoginWebsites
{
    private static final String POST_CONTENT_TYPE = "application/x-www-form-urlencoded";
    private static final String LOGIN_ACTION_NAME = "Login";
    private static final String LOGIN_USER_NAME_PARAMETER_NAME = "email";
    private static final String LOGIN_PASSWORD_PARAMETER_NAME = "pass";

    private static final String LOGIN_USER_NAME = "[email protected]";
    private static final String LOGIN_PASSWORD = "xxxxxxa@2102";





    /**
     * The single public method of this class that
     * 1. Prepares a login message
     * 2. Makes the HTTP POST to the target URL
     * 3. Reads and returns the response
     *
     * @throws IOException
     * Any problems while doing the above.
     *
     */
    public String httpPostLogin (String TARGET_URL)
    { 
        String response="";
        try
        {
            // Prepare the content to be written
            // throws UnsupportedEncodingException
            String urlEncodedContent = preparePostContent(LOGIN_USER_NAME, LOGIN_PASSWORD);

            HttpURLConnection urlConnection = doHttpPost(TARGET_URL, urlEncodedContent);

             response = readResponse(urlConnection);





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

    /**
     * Using the given username and password, and using the static string variables, prepare
     * the login message. Note that the username and password will encoded to the
     * UTF-8 standard.
     *
     * @param loginUserName
     * The user name for login
     *
     * @param loginPassword
     * The password for login
     *
     * @return
     * The complete login message that can be HTTP Posted
     *
     * @throws UnsupportedEncodingException
     * Any problems during URL encoding
     */
    private String preparePostContent(String loginUserName, String loginPassword) throws UnsupportedEncodingException
    {
        // Encode the user name and password to UTF-8 encoding standard
        // throws UnsupportedEncodingException
        String encodedLoginUserName = URLEncoder.encode(loginUserName, "UTF-8");
        String encodedLoginPassword = URLEncoder.encode(loginPassword, "UTF-8");

        String content = "login=" + LOGIN_ACTION_NAME +" &" + LOGIN_USER_NAME_PARAMETER_NAME +"="
        + encodedLoginUserName + "&" + LOGIN_PASSWORD_PARAMETER_NAME + "=" + encodedLoginPassword;

        return content;

    }

    /**
     * Makes a HTTP POST to the target URL by using an HttpURLConnection.
     *
     * @param targetUrl
     * The URL to which the HTTP POST is made.
     *
     * @param content
     * The contents which will be POSTed to the target URL.
     *
     * @return
     * The open URLConnection which can be used to read any response.
     *
     * @throws IOException
     */
    public HttpURLConnection doHttpPost(String targetUrl, String content) throws IOException
    {
        HttpURLConnection urlConnection = null;
        DataOutputStream dataOutputStream = null;
        try
        {
            // Open a connection to the target URL
            // throws IOException
            urlConnection = (HttpURLConnection)(new URL(targetUrl).openConnection());

            // Specifying that we intend to use this connection for input
            urlConnection.setDoInput(true);

            // Specifying that we intend to use this connection for output
            urlConnection.setDoOutput(true);

            // Specifying the content type of our post
            urlConnection.setRequestProperty("Content-Type", POST_CONTENT_TYPE);

            // Specifying the method of HTTP request which is POST
            // throws ProtocolException
            urlConnection.setRequestMethod("POST");

            // Prepare an output stream for writing data to the HTTP connection
            // throws IOException
            dataOutputStream = new DataOutputStream(urlConnection.getOutputStream());

            // throws IOException
            dataOutputStream.writeBytes(content);
            dataOutputStream.flush();
            dataOutputStream.close();

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

            // Good practice: clean up the connections and streams
            // to free up any resources if possible
            if (dataOutputStream != null)
            {
                try
                {
                    dataOutputStream.close();
                }
                catch(Throwable ignore)
                {
                    // Cannot do anything about problems while
                    // trying to clean up. Just ignore
                }
            }
            if (urlConnection != null)
            {
                urlConnection.disconnect();
            }

            // throw the exception so that the caller is aware that
            // there was some problems
            throw ioException;
        }
    }

    /**
     * Read response from the URL connection
     *
     * @param urlConnection
     * The URLConncetion from which the response will be read
     *
     * @return
     * The response read from the URLConnection
     *
     * @throws IOException
     * When problems encountered during reading the response from the
     * URLConnection.
     */
    private String readResponse(HttpURLConnection urlConnection) throws IOException
    {

        BufferedReader bufferedReader = null;
        try
        {
            // Prepare a reader to read the response from the URLConnection
            // throws IOException
            bufferedReader = new BufferedReader(new InputStreamReader(urlConnection.getInputStream()));
            String responeLine;

            // Good Practice: Use StringBuilder in this case
            StringBuilder response = new StringBuilder();

            // Read untill there is nothing left in the stream
            // throws IOException
            while ((responeLine = bufferedReader.readLine()) != null)
            {
                response.append(responeLine);
            }

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

            // throw the exception so that the caller is aware that
            // there was some problems
            throw ioException;

        }
        finally
        {
            // Good practice: clean up the connections and streams
            // to free up any resources if possible
            if (bufferedReader != null)
            {
                try
                {
                    // throws IOException
                    bufferedReader.close();
                }
                catch(Throwable ignore)
                {
                    // Cannot do much with exceptions doing clean up
                    // Ignoring all exceptions
                }
            }

        }
    }
}

回答by Nirmal- thInk beYond

you can not connect facebook via http connector in java to connect facebook you must use OAuth

您无法通过 Java 中的 http 连接器连接 facebook 以连接 facebook，您必须使用OAuth

see developers.facebook.comlink for detail, i reccomend to use restfb

有关详细信息，请参阅developers.facebook.com链接，我建议使用restfb