/**
 * 邮件发送组件类
 * 该类需要三个jar文件: mail.jar,activation.jar,htmlparser.jar
 * @author Winter Lau (winter.lau[at]163.com)
 * @version 1.0
 */
package lius.util.mail;
 
import java.io.File;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.Date;
import java.util.Properties;
 
import javax.activation.DataHandler;
import javax.activation.DataSource;
import javax.activation.FileDataSource;
import javax.mail.Authenticator;
import javax.mail.BodyPart;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.Multipart;
import javax.mail.PasswordAuthentication;
import javax.mail.SendFailedException;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeBodyPart;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMultipart;
 
import org.htmlparser.Node;
import org.htmlparser.Parser;
import org.htmlparser.tags.ImageTag;
import org.htmlparser.util.ParserException;
 
/**
 * 邮件发送组件,具体的使用方法参照该类的main方法
 * @author Winter Lau
 */
public abstract class MailSender extends Authenticator{
 
    private String username = null;     //邮件发送帐号用户名
    private String userpasswd = null;   //邮件发送帐号用户口令
    protected BodyPart messageBodyPart = null;
    protected Multipart multipart = new MimeMultipart(\"related\");
    protected MimeMessage mailMessage = null;
    protected Session mailSession = null;
    protected Properties mailProperties = System.getProperties();
    protected InternetAddress mailFromAddress = null;
    protected InternetAddress mailToAddress = null;
    protected Authenticator authenticator = null;
    protected String mailSubject = \"\";
    protected Date mailSendDate = null;
 
    /**
     * 构造函数
     * @param smtpHost
     * @param username
     * @param password
     */
    protected MailSender(String smtpHost, String username, String password) {
        this.username = username;
        this.userpasswd = password;
        mailProperties.put(\"mail.smtp.host\", smtpHost);
        mailProperties.put(\"mail.smtp.auth\", \"true\"); //设置smtp认证，很关键的一句
        mailSession = Session.getDefaultInstance(mailProperties, this);
        mailMessage = new MimeMessage(mailSession);
        messageBodyPart = new MimeBodyPart();
    }
    /**
     * 构造一个纯文本邮件发送实例
     * @param smtpHost
     * @param username
     * @param password
     * @return
     */
    public static MailSender getTextMailSender(String smtpHost, String username, String password) {        
        return new MailSender(smtpHost,username,password) {
            public void setMailContent(String mailContent) throws MessagingException {
                messageBodyPart.setText(mailContent);
                multipart.addBodyPart(messageBodyPart);
            }            
        };        
    }
    /**
     * 构造一个超文本邮件发送实例
     * @param smtpHost
     * @param username
     * @param password
     * @return
     */
    public static MailSender getHtmlMailSender(String smtpHost, String username, String password) {
        return new MailSender(smtpHost,username,password) {
            private ArrayList arrayList1 = new ArrayList();
            private ArrayList arrayList2 = new ArrayList();
 
            public void setMailContent(String mailContent) throws MessagingException {
                String htmlContent = getContent(\"<img src=\", mailContent);
                messageBodyPart.setContent(htmlContent, \"text/html;charset=GB2312\");
                multipart.addBodyPart(messageBodyPart);
                //调用处理html文件中的图片方法
                processHtmlImage(mailContent);
            }
 
            //处理html页面上的图片方法如下：
            private void processHtmlImage(String mailContent) throws MessagingException {
                for (int i = 0; i < arrayList1.size(); i++) {
                    messageBodyPart = new MimeBodyPart();
                    DataSource source = new FileDataSource((String) arrayList1.get(i));
                    messageBodyPart.setDataHandler(new DataHandler(source));
                    String contentId = \"<\" + (String) arrayList2.get(i) + \">\";
                    messageBodyPart.setHeader(\"Content-ID\", contentId);
                    messageBodyPart.setFileName((String) arrayList1.get(i));
                    multipart.addBodyPart(messageBodyPart);
                }
            }
 
            //处理要发送的html文件，主要是针对html文件中的图片
            private String getContent(String searchString, String mailContent) {
                try {
                    Parser parser = Parser.createParser(new String(mailContent.getBytes(), ISO8859_1));
                    Node[] images = parser.extractAllNodesThatAre(ImageTag.class);
                    for(int i=0;i<images.length;i++) {
                        ImageTag imgTag = (ImageTag) images[i];
                        if(!imgTag.getImageURL().toLowerCase().startsWith(\"http://\"))
                            arrayList1.add(imgTag.getImageURL());
                    }
                } catch (UnsupportedEncodingException e1) {
                } catch (ParserException e) {}
                String afterReplaceStr = mailContent;
                //在html文件中用\"cid:\"+Content-ID来替换原来的图片链接
                for (int m = 0; m < arrayList1.size(); m++) {
                    arrayList2.add(createRandomStr());
                    String addString = \"cid:\" + (String) arrayList2.get(m);
                    afterReplaceStr = mailContent.replaceAll(
                            (String) arrayList1.get(m), addString);
                }
                return afterReplaceStr;
            }
 
            //产生一个随机字符串，为了给图片设定Content-ID值
            private String createRandomStr() {
                char[] randomChar = new char[8];
                for (int i = 0; i < 8; i++) {
                    randomChar[i] = (char) (Math.random() * 26 + \'a\');
                }
                String replaceStr = new String(randomChar);
                return replaceStr;
            }
 
            private final static String ISO8859_1 = \"8859_1\";  
        };
    }
    /**
     * 用于实现邮件发送用户验证
     * @see javax.mail.Authenticator#getPasswordAuthentication
     */
    protected PasswordAuthentication getPasswordAuthentication() {
        return new PasswordAuthentication(username, userpasswd);
    }
     
    /**
     * 设置邮件标题
     * @param mailSubject
     * @throws MessagingException
     */
    public void setSubject(String mailSubject) throws MessagingException {
        this.mailSubject = mailSubject;
        mailMessage.setSubject(mailSubject);
    }
 
    /**
     * 所有子类都需要实现的抽象方法，为了支持不同的邮件类型
     * @param mailContent
     * @throws MessagingException
     */
    protected abstract void setMailContent(String mailContent) throws MessagingException;
 
    /**
     * 设置邮件