JAVA程序通过后台登陆网站,获取Session,然后再POST Http Request添加数据到

* 1,在HTTP的WEB应用中, 应用客户端和服务器之间的状态是通过Session来维持的, 而Session的本质就是Cookie,
* 简单的讲,当浏览器向服务器发送Http请求的时候, HTTP服务器会产生一个SessionID,这个SessionID就唯一的标识了一个客户端到服务器的请求会话过程.
* 就如同一次会议开始时,主办方给每位到场的嘉宾一个临时的编号胸牌一样, 可以通过这个编号记录每个嘉宾(客户端)的活动(请求状态).
* 为了保持这个状态, 当服务端向客户端回应的时候,会附带Cookie信息,当然,Cookie里面就包含了SessionID
* 客户端在执行一系列操作时向服务端发送请求时,也会带上这个SessionID, 一般来说,Session也是一个URL QueryParameter ,就是说,session可以以Key-Value的形式通过URL传递
* 比如,http://www.51etest.com/dede/login.php?PHPSESSIONID=7dg3dsf19SDf73wqc32fdsf
* 一般而言,浏览器会自动把此Session信息放入Header报文体中进行传递.
* 如果浏览器不支持Cookie,那么,浏览器会自动把SessionID附加到URL中去.
*
* 2,在这个例子中,以登陆这个功能点进行讲解.
* 首先,我们登陆的页面是http://www.51etest.com/dede, 我们第一次访问这个页面后,可以从服务器过来的Http Response报文中的Header中找出服务器与浏览器向关联的数据 -- Cookie,
* 而且Session的值也在Cookie中. 于是,我们可以通过分析Set-Cookie这个Header中的参数的值,找到Seesion的Key-Value段.
* 然后,我们再向服务器发送请求,请求URL为:post@@http://www.51etest.com/dede/login.php@@userid=admin&pwd=tidus2005&gotopage=/dede/&dopost=login
* 服务器验证登陆成功了, 并且在此次会话变量中增加了我们登陆成功的标识.
*
* 3,增加一个广告定义
* 增加一个广告定义其实就是一个添加数据的过程,无非是我们把我们要添加的数据通过参数的形式告诉指定url页面,页面获取后添加到数据库去而已.
* 此url地址为:
* post@@http://www.51etest.com/dede/ad_add.php@@dopost=save&tagname=test&typeid=0&adname=test&starttime=2008-05-29
* 因为这个页面会先判断我是否登陆
* 而判断的依据，前面讲了，就是根据我请求时的SessionID找到指定的Session数据区中是否存在我的登陆信息，
* 所以我当然要把访问登陆页面时获取的SessionID原封不动的再发回去
* 相当于对服务器说，这是我刚刚来时，你发我的临时身份证，我现在可以形势我的权利。
*
* 这就是整个Java后台登陆网站，然后添加数据的过程。

package cn.javadr.product;   
  
import java.io.BufferedReader;   
import java.io.IOException;   
import java.io.InputStream;   
import java.io.InputStreamReader;   
import java.io.OutputStream;   
import java.net.HttpURLConnection;   
import java.net.MalformedURLException;   
import java.net.URL;   
import java.net.URLConnection;   
import java.util.HashMap;   
import java.util.Iterator;   
import java.util.Map;   
import java.util.Map.Entry;   
  
/**  
 * HttpClient  
 *   
 * @author Tang Ren email: <a  
 *         href="mailto:[e-mail]">[e-mail]</a>  
 *   
 * <A href="mailto:post@@http://www.51etest.com/dede/login.php@@userid=xxxx&pwd=xxxxxx&gotopage=/dede/&dopost=login">post@@http://www.51etest.com/dede/login.php@@userid=xxxx&pwd=xxxxxx&gotopage=/dede/&dopost=login  
</A> *   
 * post@@http://www.51etest.com/dede/ad_add.php@@dopost=save&tagname=test&typeid=0&adname=test&starttime=2008-05-29  
 * 20:58:25&endtime=2008-06-28 20:58:25×et=0&normbody=test&expbody=test  
 *   
 */  
  
/**  
 *   
 */  
public class HttpClient {   
  
    private static final String USER_AGENT_VALUE = "Mozilla/4.0 (compatible; MSIE 6.0; Windows XP)";   
  
    /**  
     * Cmd splitor default is symbol '$$'.  
     */  
    private static final String HTTP_CLIENT_CMD_SPLITOR = "@@";   
  
    /**  
     * Post parameter splitor default is symbol '&'.  
     */  
    private static final String POST_PARAMETER_SPLITOR = "&";   
  
    private static final String POST_PARAMETER_KV_SPLITOR = "=";   
  
    private String cookie = null;   
  
    private Map cookieMap = new HashMap();   
  
    public static void main(String[] args) {   
        HttpClient client = new HttpClient();   
    }   
  
    public HttpClient() {   
        // Input http request url   
  
        BufferedReader consleReader = new BufferedReader(new InputStreamReader(   
                System.in));   
        String httpResponse = null;   
        String url = null;   
        String cmd = null;   
        String method = null;   
        try {   
            while (true) {   
                cmd = consleReader.readLine();   
                if (cmd.indexOf(HTTP_CLIENT_CMD_SPLITOR) == -1)   
                    continue;   
  
                method = cmd.split(HTTP_CLIENT_CMD_SPLITOR)[0];   
                url = cmd.split(HTTP_CLIENT_CMD_SPLITOR)[1];   
                if (method.toUpperCase().equals("GET")) {   
                    httpResponse = this.getMethod(url, true);   
                } else if (method.toUpperCase().equals("POST")) {   
                    Map parameters = this.parsePostParameters(cmd   
                            .split(HTTP_CLIENT_CMD_SPLITOR)[2]);   
                    httpResponse = this.postMethod(url, parameters, true);   
                }   
                System.out.println(httpResponse);   
            }   
        } catch (IOException e) {   
            e.printStackTrace();   
        } finally {   
            try {   
                consleReader.close();   
            } catch (IOException e) {   
                e.printStackTrace();   
            }   
        }   
  
    }   
  
    /**  
     * Request specifid url with 'GET' method. And return HTTP response content.  
     *   
     * @param url  
     * @return  
     */  
    private String getMethod(String url, boolean keepCookie) {   
        if (url == null || url.length() == 0) {   
            return "Requst url could not be null or empty.";   
        }   
  
        StringBuffer result = new StringBuffer();   
        try {   
            HttpURLConnection httpURLConnection = this.getHttpURLConnection(   
                    url, keepCookie);   
  
            // Set request properties.   
            this.settingHttpRequestHeader(httpURLConnection);   
  
            httpURLConnection.setRequestMethod("GET");   
  
            // Getting or setting cookie   
            this.gettingOrSettingCookie(httpURLConnection, keepCookie);   
  
            InputStream httpInputStream = httpURLConnection.getInputStream();   
            BufferedReader httpBufferedReader = new BufferedReader(   
                    new InputStreamReader(httpInputStream, "GBK"));   
            result.append(this.readBufferedContent(httpBufferedReader));   
  
            // Connect to host.   
            httpURLConnection.connect();   
        } catch (IOException e) {   
            e.printStackTrace();   
            return "getHttpURLConnection failed.";   
        }   
        return result.toString();   
    }   
  
    public String postMethod(String url, Map parameters, boolean keepCookie) {   
        StringBuffer httpResponse = new StringBuffer();   
  
        HttpURLConnection httpURLConnection = null;   
        OutputStream httpOutputStream = null;   
        try {   
            httpURLConnection = this.getHttpURLConnection(url, keepCookie);   
            // Set request properties.   
            this.settingHttpRequestHeader(httpURLConnection);   
  
            // Set request method with 'POST'   
            httpURLConnection.setRequestMethod("POST");   
  
            // Set connection output is true.   
            httpURLConnection.setDoOutput(true);   
            // Getting or setting cookie   
            this.gettingOrSettingCookie(httpURLConnection, keepCookie);   
            // Get Http output stream   
            httpOutputStream = httpURLConnection.getOutputStream();   
  
            // Build post parameters string   
            StringBuffer postParams = new StringBuffer();   
            int index = 0;   
            for (Iterator<Entry> iter = parameters.entrySet().iterator(); iter   
                    .hasNext(); index++) {   
                Entry<String, String> entry = iter.next();   
                postParams.append(index != 0 ? "&" : "");   
                postParams.append(entry.getKey());   
                postParams.append("=");   
                postParams.append(entry.getValue());   
            }   
            httpOutputStream.write(postParams.toString().getBytes());   
  
            BufferedReader httpBufferedReader = new BufferedReader(   
                    new InputStreamReader(httpURLConnection.getInputStream()));   
            httpResponse.append(this.readBufferedContent(httpBufferedReader));   
        } catch (IOException e) {   
            e.printStackTrace();   
            return null;   
        } finally {   
            try {   
                httpOutputStream.close();   
            } catch (IOException e) {   
                e.printStackTrace();   
            }   
        }   
  
        return httpResponse.toString();   
    }   
  
    /**  
     * Setting HTTP request header properties  
     *   
     * @param httpURLConnection  
     */  
    private void settingHttpRequestHeader(HttpURLConnection httpURLConnection) {   
        if (httpURLConnection == null)   
            return;   
        httpURLConnection.setRequestProperty("User-Agent", USER_AGENT_VALUE);   
        // TODO setting some other properties here . . .   
    }   
  
    /**  
     * Get HttpURLConnection by specified url string.  
     *   
     * @param url  
     * @return  
     * @throws IOException  
     */  
    private HttpURLConnection getHttpURLConnection(String url,   
            boolean keepCookie) throws IOException {   
        URL urlObj = new URL(url);   
        URLConnection urlConnection = urlObj.openConnection();   
        if (urlConnection instanceof HttpURLConnection)   
            return (HttpURLConnection) urlConnection;   
        throw new MalformedURLException();   
    }   
  
    /**  
     * Read bufferedReader buffered content.  
     *   
     * @param bufferedReader  
     * @return  
     */  
    private String readBufferedContent(BufferedReader bufferedReader) {   
        if (bufferedReader == null)   
            return null;   
        StringBuffer result = new StringBuffer();   
        String line = null;   
        try {   
            while ((line = bufferedReader.readLine()) != null) {   
                result.append(line);   
            }   
        } catch (IOException e) {   
            e.printStackTrace();   
            return null;   
        }   
        return result.toString();   
    }   
  
    /**  
     * Parse and create parameter map with parameter string  
     *   
     * @param parameterString  
     * @return  
     */  
    private Map parsePostParameters(String parameterString) {   
        if (parameterString == null || parameterString.length() == 0)   
            return null;   
        Map result = new HashMap<String, String>();   
  
        // only one parameter key-value pair   
        if (parameterString.indexOf(POST_PARAMETER_SPLITOR) == -1) {   
            if (parameterString.indexOf(POST_PARAMETER_KV_SPLITOR) != -1)   
                result.put(parameterString.split(POST_PARAMETER_KV_SPLITOR)[0],   
                        parameterString.split(POST_PARAMETER_KV_SPLITOR)[1]);   
        } else {   
            String[] keyValues = parameterString.split(POST_PARAMETER_SPLITOR);   
            for (int i = 0; i < keyValues.length; i++) {   
                String keyValue = keyValues[i];   
                result.put(keyValue.split(POST_PARAMETER_KV_SPLITOR)[0],   
                        keyValue.split(POST_PARAMETER_KV_SPLITOR)[1]);   
            }   
        }   
        return result;   
    }   
  
    /**  
     * Get or set cookie.  
     *   
     * @param httpURLConnection  
     * @param keepCookie  
     */  
    private void gettingOrSettingCookie(HttpURLConnection httpURLConnection,   
            boolean keepCookie) {   
        // Getting or setting cookie.   
        if (cookie == null || cookie.length() == 0) {   
            String setCookie = httpURLConnection.getHeaderField("Set-Cookie");   
            cookie = setCookie.substring(0, setCookie.indexOf(";"));   
        } else if (keepCookie) {   
            httpURLConnection.setRequestProperty("Cookie", cookie);   
        }   
    }   
}