java入门教程：网络通信例子(一)

java网络通信例基础入门教程一

 

文件ExtendString.java

 

package chapter09.sample9_1;

public class ExtendString {
	  public ExtendString() {
	  }
	  /**
	   去掉字符串两端的空白字符,并将字符串转化为中国的标准字符gb2312的字符串.
	   */
	  public String CS(String str) { //去掉字符串2端的空白字符
	      try {
	          if (str == null)
	              return "";
	          str = str.trim();
	          if (str == null)
	              return "";
	          str = new String(str.getBytes("8859_1"), "GBK");
	      }
	      catch (Exception e) {
	          System.out.println(e);
	      }
	      return str;
	  }


}

 

文件MailSender.java

 

package chapter09.sample9_1;
import java.io.*;
import java.util.*;
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; 



public class MailSender {
	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); 
        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 void setMailContent(String mailContent) throws MessagingException {
	} 

    /** 
     * 设置邮件发送日期 
     * @param sendDate 
     * @throws MessagingException 
     */ 
    public void setSendDate(Date sendDate) throws MessagingException { 
        this.mailSendDate = sendDate; 
        mailMessage.setSentDate(sendDate); 
    } 

    /** 
     * 设置邮件发送附件 
     * @param attachmentName 
     * @throws MessagingException 
     */ 
    public void setAttachments(String attachmentName) throws MessagingException { 
        messageBodyPart = new MimeBodyPart(); 
        DataSource source = new FileDataSource(attachmentName); 
        messageBodyPart.setDataHandler(new DataHandler(source)); 
        int index = attachmentName.lastIndexOf(File.separator); 
        String attachmentRealName = attachmentName.substring(index + 1); 
        messageBodyPart.setFileName(attachmentRealName); 
        multipart.addBodyPart(messageBodyPart); 
    } 

    /** 
     * 设置发件人地址 
     * @param mailFrom 
     * @throws MessagingException 
     */ 
    public void setMailFrom(String mailFrom) throws MessagingException { 
        mailFromAddress = new InternetAddress(mailFrom); 
        mailMessage.setFrom(mailFromAddress); 
    } 

    /** 
     * 设置收件人地址，收件人类型为to,cc,bcc(大小写不限) 
     * @param mailTo   邮件接收者地址 
     * @param mailType 值为to,cc,bcc 
     * @author Liudong 
     */ 
    public void setMailTo(String[] mailTo, String mailType) throws Exception { 
        for (int i = 0; i < mailTo.length; i++) { 
            mailToAddress = new InternetAddress(mailTo[i]); 
            if (mailType.equalsIgnoreCase("to")) { 
                mailMessage.addRecipient(Message.RecipientType.TO,mailToAddress); 
            } else if (mailType.equalsIgnoreCase("cc")) { 
                mailMessage.addRecipient(Message.RecipientType.CC,mailToAddress); 
            } else if (mailType.equalsIgnoreCase("bcc")) { 
                mailMessage.addRecipient(Message.RecipientType.BCC,mailToAddress); 
            } else { 
                throw new Exception("Unknown mailType: " + mailType + "!"); 
            } 
        } 
    } 
    /** 
     * 开始发送邮件 
     * @throws MessagingException 
     * @throws SendFailedException 
     */ 
    public void sendMail() throws MessagingException, SendFailedException { 
        if (mailToAddress == null) 
            throw new MessagingException("请你必须你填写收件人地址！"); 
        mailMessage.setContent(multipart); 
        Transport.send(mailMessage); 
    } 

    /** 
     * 邮件发送测试 
     * @param args 
     */ 
    public static void main(String args[]) { 
        String mailHost = "smtp.gmail.com"; //发送邮件服务器地址 
        String mailUser = "hujie1982";   //发送邮件服务器的用户帐号 
        String mailPassword = "123456";   //发送邮件服务器的用户密码 
        String[] toAddress = {"[e-mail]"}; 
        //使用超文本格式发送邮件 
        MailSender sendmail = MailSender.getHtmlMailSender(mailHost, mailUser,mailPassword); 
        //使用纯文本格式发送邮件 
        //MailSender sendmail = MailSender.getTextMailSender(mailHost, mailUser,mailPassword); 
        try { 
            sendmail.setSubject("要发送的标题？"); 
            sendmail.setSendDate(new Date()); 
            String content = "hello world"; 
            //请注意如果是本地图片比如使用斜杠作为目录分隔符,如下所示,不支持中文？？？！！！ 
           // content+="<img src=\"C:/Documents and Settings/Administrator/My Documents/My Pictures/aaa.jpg\"/>"; 
            //sendmail.setMailContent(content); // 
            //sendmail.setAttachments("E:\\ConList.exe");//文章附件 
            sendmail.setMailFrom("[e-mail]");//显示谁发送的 
            sendmail.setMailTo(toAddress, "to");//cc抄送，bcc 暗送 
            //sendmail.setMailTo(toAddress, "cc");//设置抄送给... 
            //开始发送邮件 
            System.out.println("正在发送邮件，请稍候......."); 
            sendmail.sendMail(); 
            System.out.println("恭喜你，邮件已经成功发送!"); 
        } catch (Exception ex) { 
            ex.printStackTrace(); 
        } 
    } 
}

 

文件Sample9_1.java

 

package chapter09.sample9_1;

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

public class Sample9_1 {
	public static void main(String[] args)
			{
				try
				{
					//创建URL对象
					URL url=new URL("http://www.sina.com");
					//打开指向资源的输入流
					InputStream in=url.openStream();
					//将输入流由字节流转换为字符流
					InputStreamReader isr=new InputStreamReader(in);
					//将输入流封装为缓冲输入处理流
					BufferedReader br=new BufferedReader(isr);
					//创建输出流，并指定目标文件
					BufferedWriter bw=new BufferedWriter(new FileWriter("c:/URL.html"));
					//对输出流进一步进行封装
					PrintWriter pw=new PrintWriter(bw);
					//声明临时字符串引用
					String temps=null;
					//从输入流中获取资源并测试是否读取完毕
					while((temps=br.readLine())!=null)
					{

						//将获取的数据写如目标文件
						pw.println(temps);
					}
					//打印提示信息
					System.out.println("恭喜您，资源已经获取完毕，并将其写入了URL.html文件中！！！");
					//关闭输入流与输出流
					pw.close();
					br.close();
				}
				catch(Exception e)
				{
					e.printStackTrace();
				}
			}
}

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