HttpsURLConnection 安全传输（HTTPS--Secure Hypertext Transfer Protocol-安全超文本传输协议）

HttpsURLConnection 扩展 HttpURLConnection，支持各种特定于 https 功能。此类使用 HostnameVerifier 和 SSLSocketFactory。为这两个类都定义了默认实现。但是，可以根据每个类（静态的）或每个实例来替换该实现。所有新 HttpsURLConnection 实例在创建时将被分配“默认的”静态值，通过在连接前调用每个实例适当的 set 方法可以重写这些值

在URL前加https://前缀表明是用SSL加密的。 你的电脑与服务器之间收发的信息传输将更加安全。

Web服务器启用SSL需要获得一个服务器证书并将该证书与要使用SSL的服务器绑定。 
http和https使用的是完全不同的连接方式,用的端口也不一样,前者是80,后者是443。http的连接很简单,是无状态的,...

HTTPS协议是由SSL+HTTP协议构建的可进行加密传输、身份认证的网络协议 
要比http协议安全

import java.io.*;
import java.net.*;
import java.security.*;
import java.security.cert.*;
import javax.net.ssl.*;

public class HttpsURLConnectionTest {

    private String url = "https://esales.the9.com/esa/DealerLogin.php?txt_sLogin=andysmile234&pas_sPwd=343211&userstatus=1";

    private myX509TrustManager xtm = new myX509TrustManager();

    private myHostnameVerifier hnv = new myHostnameVerifier();

    public HttpsURLConnectionTest() {
        SSLContext sslContext = null;
        try {
            sslContext = SSLContext.getInstance("TLS"); //或SSL
            X509TrustManager[] xtmArray = new X509TrustManager[] {xtm};
            sslContext.init(null, xtmArray, new java.security.SecureRandom());
        } catch (GeneralSecurityException e) {
            e.printStackTrace();
        }
        if (sslContext != null) {
            HttpsURLConnection.setDefaultSSLSocketFactory(sslContext.getSocketFactory());
        }
        HttpsURLConnection.setDefaultHostnameVerifier(hnv);
    }

    public void run() {
        HttpsURLConnection urlCon = null;
        try {
            urlCon = (HttpsURLConnection)(new URL(url)).openConnection();
            urlCon.setDoOutput(true);
            urlCon.setRequestMethod("POST");
            urlCon.setRequestProperty("Content-Length", "1024");
            urlCon.setUseCaches(false);
            urlCon.setDoInput(true);
            urlCon.getOutputStream().write("request content".getBytes("gbk"));
            urlCon.getOutputStream().flush();
            urlCon.getOutputStream().close();
            BufferedReader in = new BufferedReader(new InputStreamReader(urlCon.getInputStream()));
            String line;
            while ((line = in.readLine()) != null) {
                System.out.println(line);
            }
            // 增加自己的代码
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public static void main(String[] args) {
        HttpsURLConnectionTest httpsTest = new HttpsURLConnectionTest();
        httpsTest.run();
    }
}

/**
 * 重写三个方法
 * @author Administrator
 *
 */
class myX509TrustManager implements X509TrustManager {

    public void checkClientTrusted(X509Certificate[] chain, String authType) {
    }

    public void checkServerTrusted(X509Certificate[] chain, String authType) {
        System.out.println("cert: " + chain[0].toString() + ", authType: " + authType);
    }

    public X509Certificate[] getAcceptedIssuers() {
        return null;
    }
}

/**
 * 重写一个方法
 * @author Administrator
 *
 */
class myHostnameVerifier implements HostnameVerifier {

    public boolean verify(String hostname, SSLSession session) {
        System.out.println("Warning: URL Host: " + hostname + " vs. " + session.getPeerHost());
        return true;
    }
}

以下摘自：http://www.zimbio.com/member/kinggod03/articles/HImNQwJm-Lp/ 
 终于完成了博客备份的程序，自己一直想做的事情算是完成了。发扬怀疑一切的精神，真不放心把自己的帐号告诉其他的公司，让他们来备份。闲来无事，也为了让我玩实况累的发软的手体验一下敲代码的感觉，专心的做完了这个备份博客的程序。总共有300多行，功能其实也很简单，就是把每篇文章的网页保存起来 ，但第一次做这种网络程序，很多都要学习。下面列出几点收获： 
1，登陆需要使用SSL协议，似乎封装的太好了——只是把代码烤过来，很简单，现在也没懂是啥意思
2,使用Cookie。登录之后究竟用什么保存SessionID，头疼了很长时间。用IE进行登陆，把Cookie设成“提示”，于是所有的暗箱操作都见了阳光。这时才知道，几乎每个网页都会用Cookie存些东西，哪还有隐私。百度是必须用Cookie的，否则就无法登陆。这样有些过分了，应该提供一个选择。得到Cookie值后需要把“PASSPORTRETRYSTRING=deleted;”去掉，这个字段应该是用于防止重复提交的。如果不去掉，相当于没有登陆。去掉之后的Cookie值（主要是BDUUSS和BDUID）可以发送到服务器，这样就以登陆用户的身份查看博客了。
3，对于HTML代码应该可以用XML的方式来处理，不过我没有那个耐心，就用字符串的替代查找来实现了，效率不好，可以改进。
4，连接那部分代码借鉴了Google提供的博客访问的源代码，受益匪浅。百度没有相应的API，要不然我也不用这么麻烦。
5，还有许多细节的东西，比如文件读写啦。
6，看HTML代码真是头大！！！
为了取得信任我就把源代码贴出来，这也是我不愿意用那些商业软件的原因。商业软件，赚钱是最主要的，他不信任我，我也不信任他。而我，只不过图个安心和方便。

/**
 * 本程序可用于备份百度空间的文章。
 * 18 hours costed.
 * niuys.
 * 2007.7.11
 */
import java.io.*;
import java.net.*;
import java.security.GeneralSecurityException;
import java.security.cert.X509Certificate;
import java.util.*;

import javax.net.ssl.HostnameVerifier;
import javax.net.ssl.HttpsURLConnection;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLSession;
import javax.net.ssl.X509TrustManager;

public class OpticalBackup {
    // 把博客信息应编码
    private String urlString = "https://passport.baidu.com/?login";

    // 保存的目录
    private String saveDir = "L:\\blogBackup";

    // 博客的根路径
    private String spaceRoot = "http://hi.baidu.com/niuys/blog/index/";

    private String articleURLHead = "/niuys/blog/item/";

    // parameters needed to log in.
    Map parameters = new HashMap();

    // 建立连接需要使用cookie提供的sessionID.
    String cookieVal = null;

    // Create an anonymous class to trust all certificates.
    // This is bad style, you should create a separate class.
    private X509TrustManager xtm = new X509TrustManager() {
        public void checkClientTrusted(X509Certificate[] chain, String authType) {
        }

        public void checkServerTrusted(X509Certificate[] chain, String authType) {
            // System.out.println("cert: " + chain[0].toString() + ", authType:
            // "
            // + authType);
        }

        public X509Certificate[] getAcceptedIssuers() {
            return null;
        }
    };

    // Create an class to trust all hosts
    private HostnameVerifier hnv = new HostnameVerifier() {
        public boolean verify(String hostname, SSLSession session) {
            // System.out.println("hostname: " + hostname);
            return true;
        }
    };

    // In this function we configure our system with a less stringent
    // hostname verifier and X509 trust manager. This code is
    // executed once, and calls the static methods of HttpsURLConnection
    public OpticalBackup() {
        // The parameters needed to log on.
        parameters.put("username", "保密");
        parameters.put("password", "保密");
        parameters.put("Submit", " 登录 ");
        parameters.put("tpl", "sp");
        parameters.put("tpl_reg", "sp");
        parameters.put("u", "http://www.baidu.com/");

        // check the saveDir
        File dir = new File(saveDir);
        if (!dir.exists()) {
            dir.mkdir();
        }

        // Initialize the TLS SSLContext with
        // our TrustManager
        SSLContext sslContext = null;
        try {
            sslContext = SSLContext.getInstance("TLS");
            X509TrustManager[] xtmArray = new X509TrustManager[] {xtm};
            sslContext.init(null, xtmArray, new java.security.SecureRandom());
        } catch (GeneralSecurityException e) {
            // Print out some error message and deal with this exception
            e.printStackTrace();
        }

        // Set the default SocketFactory and HostnameVerifier
        // for javax.net.ssl.HttpsURLConnection
        if (sslContext != null) {
            HttpsURLConnection.setDefaultSSLSocketFactory(sslContext.getSocketFactory());
        }
        HttpsURLConnection.setDefaultHostnameVerifier(hnv);
    }

    // the whole process
    public void run() {
        try {
            URL url = new URL(urlString);
            HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();

            // Set properties of the connection
            urlConnection.setDoInput(true);
            urlConnection.setDoOutput(true);
            urlConnection.setUseCaches(false);
            urlConnection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");

            // Form the POST parameters
            StringBuilder content = new StringBuilder();
            boolean first = true;
            Set set = parameters.entrySet();
            Iterator iterator = set.iterator();
            Map.Entry parameter = (Map.Entry) iterator.next();
            try {
                while (parameter != null) {
                    if (!first) {
                        content.append("&");
                    }
                    content.append(URLEncoder.encode((String) parameter.getKey(), "UTF-8")).append("=");
                    content.append(URLEncoder.encode((String) parameter.getValue(), "UTF-8"));
                    first = false;
                    parameter = (Map.Entry) iterator.next();
                }
            } catch (NoSuchElementException e) {
                e.printStackTrace();
            }

            // send the POST request to server
            OutputStream outputStream = null;
            try {
                outputStream = urlConnection.getOutputStream();
                outputStream.write(content.toString().getBytes("utf-8"));
                outputStream.flush();
            } finally {
                if (outputStream != null) {
                    outputStream.close();
                }
            }

            // Retrieve the output
            InputStream inputStream = null;
            StringBuilder outputBuilder = new StringBuilder();
            try {
                int responseCode = urlConnection.getResponseCode();
                if (responseCode == HttpURLConnection.HTTP_OK) {
                    inputStream = urlConnection.getInputStream();
                } else {
                    inputStream = urlConnection.getErrorStream();
                }

                String string;
                if (inputStream != null) {
                    BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
                    while (null != (string = reader.readLine())) {
                        outputBuilder.append(string).append('\n');
                    }
                }

                // get the cookie value in the header filelds
                Map map = urlConnection.getHeaderFields();
                Collection collection = map.values();
                Object[] values = collection.toArray();
                // values[4].toString() is nedded .Otherwise,an exception
                // throws. Direct class cast is forbidded.
                cookieVal = (String) values[4].toString();

                // "replaceAll()" requests that if "[" exits, "]" is nedded
                // too.This is the diffrence from "replace()".
                cookieVal = cookieVal.replace(']', ' ').replace("[PASSPORTRETRYSTRING=deleted; expires=Mon, 01 Jan 1970 00:00:00 GMT; path=/;", "");// remedy the first key from cookie
            } finally {
                if (inputStream != null) {
                    inputStream.close();
                }
            }

            // find all the URLs of the articles you write.
            ArrayList pageURLs = findLinkers();

            // save all the articles
            for (int i = 0; i < pageURLs.size(); i++) {
                savePage((String) pageURLs.get(i));
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    // save the article with the URL
    private void savePage(String pageURL) {
        try {
            // create the file to accept the output.The file's name is a part of
            // the URL
            File pageFile = new File(saveDir + "\\" + pageURL.substring(36));

            // 增量备份
            if (pageFile.exists())
                return;
            FileWriter fw = new FileWriter(pageFile);

            // create the connection to the server,and get the results.
            URL url = new URL(pageURL);
            String content = getContentFromURL(url);

            // write the contents to the file.
            fw.write(content);
            // flush the contents in the buffer.Without
            // it,the file's content may be not completed.
            fw.flush();
            fw.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    // find all the articles' URL from the html code accepted from the server
    private ArrayList findLinkers() {
        // the index of the articles
        int i = 0;
        ArrayList linkers = new ArrayList();
        URL url = null;

        try {
            while (true) {
                url = new URL(spaceRoot + i);
                System.out.println("url==" + url);
                i++;// next index
                // get the content from server
                String content = getContentFromURL(url);
                // Analyze the content.
                ArrayList temp = getLinkerFromContent(content);
                if (temp.isEmpty())// no article url exists
                    return linkers;

                linkers.addAll(temp);// combine the URLs
            }
        } catch (Exception e) {
            e.printStackTrace();
        }

        return linkers;
    }

    private ArrayList getLinkerFromContent(String content) {
        ArrayList linkerArray = new ArrayList();
        String linker = null;
        // The article's URL begins with "/niuys/blog/item/"
        int index = content.indexOf(articleURLHead);
        if (content.indexOf("暂无文章") > 0) {// 超过页数时会返回包含“暂无文章”的页,end
            return linkerArray;
        }

        // deal with the content
        while (index > 0) {
            // get the whole URL
            linker = content.substring(index, index + 46);
            content = content.replace(linker, "");
            index = content.indexOf(articleURLHead);
            linker = "http://hi.baidu.com" + linker;
            linkerArray.add(linker);

            System.out.println("linker==" + linker);
        }

        return linkerArray;
    }

    private String getContentFromURL(URL url) throws Exception {
        HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();

        // Set properties of the connection
        urlConnection.setDoInput(true);
        urlConnection.setDoOutput(true);
        urlConnection.setUseCaches(false);
        urlConnection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
        urlConnection.addRequestProperty("Cookie", cookieVal);

        // Retrieve the output
        InputStream inputStream = null;
        StringBuilder outputBuilder = new StringBuilder();

        int responseCode = urlConnection.getResponseCode();
        if (responseCode == HttpURLConnection.HTTP_OK) {
            inputStream = urlConnection.getInputStream();
        } else {
            inputStream = urlConnection.getErrorStream();
        }

        String string;
        if (inputStream != null) {
            BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
            while (null != (string = reader.readLine())) {
                outputBuilder.append(string).append('\n');
            }
            inputStream.close();
            return outputBuilder.toString();
        }
        return "";
    }

    public static void main(String[] args) {
        OpticalBackup backup = new OpticalBackup();
        backup.run();
    }

}