如何写一个JAVA类可以实现邮件发送功能,也可以实现群发功能

Question

[color=red][/color]

 

Answer 1

[code="java"]package byd.core;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.io.UnsupportedEncodingException;
import java.net.Socket;
import java.nio.charset.Charset;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import sun.misc.BASE64Encoder;

/**

• 该类使用Socket连接到邮件服务器， 并实现了向指定邮箱发送邮件及附件的功能。

• @author Kou Hongtao
  */
  public class Email {

  /**

  • 换行符 */ private static final String LINE_END = "\r\n";

  /**

  • 值为“true”输出高度信息（包括服务器响应信息），值为“ false”则不输出调试信息。 */ private boolean isDebug = true;

  /**

  • 值为“true”则在发送邮件{@link Mail#send()} 过程中会读取服务器端返回的消息，
  • 并在邮件发送完毕后将这些消息返回给用户。 */ private boolean isAllowReadSocketInfo = true;

  /**

  • 邮件服务器地址 */ private String host;

  /**

  • 发件人邮箱地址 */ private String from;

  /**

  • 收件人邮箱地址 */ private List to;

  /**

  • 抄送地址 */ private List cc;

  /**

  • 暗送地址 */ private List bcc;

  /**

  • 邮件主题 */ private String subject;

  /**

  • 用户名 */ private String user;

  /**

  • 密码 */ private String password;

  /**

  • MIME邮件类型 */ private String contentType;

  /**

  • 用来绑定多个邮件单元{@link #partSet}
  • 的分隔标识，我们可以将邮件的正文及每一个附件都看作是一个邮件单元 。 */ private String boundary;

  /**

  • 邮件单元分隔标识符，该属性将用来在邮件中作为分割各个邮件单元的标识 。 */ private String boundaryNextPart;

  /**

  • 传输邮件所采用的编码 */ private String contentTransferEncoding;

  /**

  • 设置邮件正文所用的字符集 */ private String charset;

  /**

  • 内容描述 */ private String contentDisposition;

  /**

  • 邮件正文 */ private String content;

  /**

  • 发送邮件日期的显示格式 */ private String simpleDatePattern;

  /**

  • 附件的默认MIME类型 */ private String defaultAttachmentContentType;

  /**

  • 邮件单元的集合，用来存放正文单元和所有的附件单元。 */ private List partSet;

  private List alternativeList;

  private String mixedBoundary;

  private String mixedBoundaryNextPart;

  /**

  • 不同类型文件对应的{@link MIME} 类型映射。在添加附件
  • {@link #addAttachment(String)} 时，程序会在这个映射中查找对应文件的
  • {@link MIME} 类型，如果没有， 则使用
  • {@link #defaultAttachmentContentType} 所定义的类型。 */ private static Map contentTypeMap;

  private static enum TextType {
  PLAIN("plain"), HTML("html");

  private String v;
  
  private TextType(String v) {
      this.v = v;
  }
  
  public String getValue() {
      return this.v;
  }
  

  }

  static {
  // MIME Media Types
  contentTypeMap = new HashMap();
  contentTypeMap.put("xls", "application/vnd.ms-excel");
  contentTypeMap.put("xlsx", "application/vnd.ms-excel");
  contentTypeMap.put("xlsm", "application/vnd.ms-excel");
  contentTypeMap.put("xlsb", "application/vnd.ms-excel");
  contentTypeMap.put("doc", "application/msword");
  contentTypeMap.put("dot", "application/msword");
  contentTypeMap.put("docx", "application/msword");
  contentTypeMap.put("docm", "application/msword");
  contentTypeMap.put("dotm", "application/msword");
  }

  /**

  • 该类用来实例化一个正文单元或附件单元对象，他继承了 {@link Mail}
  • ，在这里制作这个子类主要是为了区别邮件单元对象和邮件服务对象 ，使程序易读一些。
  • 这些邮件单元全部会放到partSet 中，在发送邮件 {@link #send()}时, 程序会调用
  • {@link #getAllParts()} 方法将所有的单元合并成一个符合MIME格式的字符串。
  • @author Kou Hongtao */ private class MailPart extends Email { public MailPart() { } }

  /**

  • 默认构造函数 */ public Email() { defaultAttachmentContentType = "application/octet-stream"; simpleDatePattern = "yyyy-MM-dd HH:mm:ss"; boundary = "--=_NextPart_zlz_3907_" + System.currentTimeMillis(); boundaryNextPart = "--" + boundary; contentTransferEncoding = "base64"; contentType = "multipart/mixed"; charset = Charset.defaultCharset().name(); partSet = new ArrayList(); alternativeList = new ArrayList(); to = new ArrayList(); cc = new ArrayList(); bcc = new ArrayList(); mixedBoundary = "=NextAttachment_zlz_" + System.currentTimeMillis(); mixedBoundaryNextPart = "--" + mixedBoundary; }

  /**

  • 根据指定的完整文件名在 {@link #contentTypeMap} 中查找其相应的MIME类型，
  • 如果没找到，则返回 {@link #defaultAttachmentContentType}
  • 所指定的默认类型。
  • @param fileName
  • 文件名

  • @return 返回文件对应的MIME类型。
    */
    private String getPartContentType(String fileName) {
    String ret = null;
    if (null != fileName) {
    int flag = fileName.lastIndexOf(".");
    if (0 <= flag && flag < fileName.length() - 1) {
    fileName = fileName.substring(flag + 1);
    }
    ret = contentTypeMap.get(fileName);
    }

    if (null == ret) {
    ret = defaultAttachmentContentType;
    }
    return ret;
    }

  /**

  • 将给定字符串转换为base64编码的字符串
  • @param str
  • 需要转码的字符串
  • @param charset
  • 原字符串的编码格式
  • @return base64编码格式的字符 */ private String toBase64(String str, String charset) { if (null != str) { try { return toBase64(str.getBytes(charset)); } catch (UnsupportedEncodingException e) { e.printStackTrace(); } } return ""; }

  /**

  • 将指定的字节数组转换为base64格式的字符串
  • @param bs
  • 需要转码的字节数组
  • @return base64编码格式的字符 */ private String toBase64(byte[] bs) { return new BASE64Encoder().encode(bs); }

  /**

  • 将给定字符串转换为base64编码的字符串
  • @param str
  • 需要转码的字符串
  • @return base64编码格式的字符 */ private String toBase64(String str) { return toBase64(str, Charset.defaultCharset().name()); }

  /**

  • 将所有的邮件单元按照标准的MIME格式要求合并。

  • @return 返回一个所有单元合并后的字符串。
    */
    private String getAllParts() {

    StringBuilder sbd = new StringBuilder(LINE_END);
    sbd.append(mixedBoundaryNextPart);
    sbd.append(LINE_END);
    sbd.append("Content-Type: ");
    sbd.append("multipart/alternative");
    sbd.append(";");
    sbd.append("boundary=\"");
    sbd.append(boundary).append("\""); // 邮件类型设置
    sbd.append(LINE_END);
    sbd.append(LINE_END);
    sbd.append(LINE_END);
    addPartsToString(alternativeList, sbd, getBoundaryNextPart());
    sbd.append(getBoundaryNextPart()).append("--");
    sbd.append(LINE_END);

    addPartsToString(partSet, sbd, mixedBoundaryNextPart);

    sbd.append(LINE_END);
    sbd.append(mixedBoundaryNextPart).append("--");
    sbd.append(LINE_END);
    // sbd.append(boundaryNextPart).
    // append(LINE_END);
    alternativeList.clear();
    partSet.clear();
    return sbd.toString();
    }

  private void addPartsToString(List list, StringBuilder sbd,
  String nextPartString) {
  int partCount = list.size();
  for (int i = 0; i < partCount; i++) {
  Email attachment = list.get(i);
  String attachmentContent = attachment.getContent();
  if (null != attachmentContent && 0 < attachmentContent.length()) {
  sbd.append(nextPartString).append(LINE_END);
  sbd.append("Content-Type: ");
  sbd.append(attachment.getContentType());
  sbd.append(LINE_END);
  sbd.append("Content-Transfer-Encoding: ");
  sbd.append(attachment.getContentTransferEncoding());
  sbd.append(LINE_END);
  String cd = attachment.getContentDisposition();
  if (null != cd) {
  sbd.append("Content-Disposition: ");
  sbd.append(cd);
  sbd.append(LINE_END);
  }

          sbd.append(LINE_END);
          sbd.append(attachmentContent);
          sbd.append(LINE_END);
      }
  }
  

  }

  /**

  • 添加邮件正文单元 */ private void addContent() { if (null != content) { MailPart part = new MailPart(); part.setContent(toBase64(content)); part.setContentType("text/plain;charset=\"" + charset + "\""); alternativeList.add(part); } }

  private String listToMailString(List mailAddressList) {
  StringBuilder sbd = new StringBuilder();
  if (null != mailAddressList) {
  int listSize = mailAddressList.size();
  for (int i = 0; i < listSize; i++) {
  if (0 != i) {
  sbd.append(";");
  }
  sbd.append("<").append(mailAddressList.get(i)).append(">");
  }
  }
  return sbd.toString();
  }

  private List getrecipient() {
  List list = new ArrayList();
  list.addAll(to);
  list.addAll(cc);
  list.addAll(bcc);
  return list;
  }

  /**

  • 添加超文本内容
  • @param text */ public void addHtmlContent(String text) { addContent(text, TextType.HTML); }

  /**

  • 添加纯文本内容
  • @param text */ public void addTextContent(String text) { addContent(text, TextType.PLAIN); }

  private void addContent(String text, TextType type) {
  if (null != text) {
  MailPart part = new MailPart();
  part.setContent(toBase64(text));
  part.setContentType("text/" + type.getValue() + ";charset=\""
  + charset + "\"");
  alternativeList.add(part);
  }
  }

  /**

  • 添加一个附件单元
  • @param filePath
  • 文件路径 */ public void addAttachment(String filePath) { addAttachment(filePath, null); }

  public void addTo(String mailAddress) {
  this.to.add(mailAddress);
  }

  public void addCc(String mailAddress) {
  this.cc.add(mailAddress);
  }

  public void addBcc(String mailAddress) {
  this.bcc.add(mailAddress);
  }

  /**

  • 添加一个附件单元
  • @param filePath
  • 文件路径
  • @param charset
  • 文件编码格式 */ public void addAttachment(String filePath, String charset) { if (null != filePath && filePath.length() > 0) { File file = new File(filePath); try { addAttachment(file.getName(), new FileInputStream(file), charset); } catch (FileNotFoundException e) { System.out.println("错误：" + e.getMessage()); System.exit(1); } } }

  /**

  • 添加一个附件单元
  • @param fileName
  • 文件名
  • @param attachmentStream
  • 文件流
  • @param charset

  •        文件编码格式
    

    */
    public void addAttachment(String fileName, InputStream attachmentStream,
    String charset) {
    try {

    byte[] bs = null;
    if (null != attachmentStream) {
        int buffSize = 1024;
        byte[] buff = new byte[buffSize];
        byte[] temp;
        bs = new byte[0];
        int readTotal = 0;
        while (-1 != (readTotal = attachmentStream.read(buff))) {
            temp = new byte[bs.length];
            System.arraycopy(bs, 0, temp, 0, bs.length);
            bs = new byte[temp.length + readTotal];
            System.arraycopy(temp, 0, bs, 0, temp.length);
            System.arraycopy(buff, 0, bs, temp.length, readTotal);
        }
    }
    
    if (null != bs) {
        MailPart attachmentPart = new MailPart();
        charset = null != charset ? charset : Charset.defaultCharset()
                .name();
        String contentType = getPartContentType(fileName)
                + ";name=\"=?" + charset + "?B?" + toBase64(fileName)
                + "?=\"";
        attachmentPart.setCharset(charset);
        attachmentPart.setContentType(contentType);
        attachmentPart.setContentDisposition("attachment;filename=\"=?"
                + charset + "?B?" + toBase64(fileName) + "?=\"");
        attachmentPart.setContent(toBase64(bs));
        partSet.add(attachmentPart);
    }
    

    } catch (Exception e) {
    e.printStackTrace();
    } finally {
    if (null != attachmentStream) {
    try {
    attachmentStream.close();
    attachmentStream = null;
    } catch (IOException e) {
    e.printStackTrace();
    }
    }

    Runtime.getRuntime().gc();
    Runtime.getRuntime().runFinalization();
    

    }
    }

  /**

  • 发送邮件

  • @return 邮件服务器反回的信息
    */
    public String send() {

    // 对象申明
    // 当邮件发送完毕后，以下三个对象（Socket、
    // PrintWriter,
    // BufferedReader）需要关闭。
    Socket socket = null;
    PrintWriter pw = null;
    BufferedReader br = null;

    try {
    socket = new Socket(host, 25);
    pw = new PrintWriter(socket.getOutputStream());
    br = new BufferedReader(new InputStreamReader(socket
    .getInputStream()));

    StringBuilder infoBuilder = new StringBuilder(
            "\nServer info: \n------------\n");
    
    // 与服务器建立连接
    pw.write("HELO ".concat(host).concat(LINE_END)); // 连接到邮件服务
    if (!readResponse(pw, br, infoBuilder, "220"))
        return infoBuilder.toString();
    
    pw.write("AUTH LOGIN".concat(LINE_END)); // 登录
    if (!readResponse(pw, br, infoBuilder, "250"))
        return infoBuilder.toString();
    
    pw.write(toBase64(user).concat(LINE_END)); // 输入用户名
    if (!readResponse(pw, br, infoBuilder, "334"))
        return infoBuilder.toString();
    
    pw.write(toBase64(password).concat(LINE_END)); // 输入密码
    if (!readResponse(pw, br, infoBuilder, "334"))
        return infoBuilder.toString();
    
    pw.write("MAIL FROM:<" + from + ">" + LINE_END); // 发件人邮箱地址
    if (!readResponse(pw, br, infoBuilder, "235"))
        return infoBuilder.toString();
    
    List<String> recipientList = getrecipient();
    // 收件邮箱地址
    for (int i = 0; i < recipientList.size(); i++) {
        pw.write("RCPT TO:<" + recipientList.get(i) + ">" + LINE_END);
        if (!readResponse(pw, br, infoBuilder, "250"))
            return infoBuilder.toString();
    }
    // System.out.println(
    // getAllSendAddress());
    
    pw.write("DATA" + LINE_END); // 开始输入邮件
    if (!readResponse(pw, br, infoBuilder, "250"))
        return infoBuilder.toString();
    
    flush(pw);
    
    // 设置邮件头信息
    StringBuffer sbf = new StringBuffer("From: <" + from + ">"
            + LINE_END); // 发件人
    sbf.append("To: " + listToMailString(to) + LINE_END);// 收件人
    sbf.append("Cc: " + listToMailString(cc) + LINE_END);// 收件人
    sbf.append("Bcc: " + listToMailString(bcc) + LINE_END);// 收件人
    sbf.append("Subject: " + subject + LINE_END);// 邮件主题
    SimpleDateFormat sdf = new SimpleDateFormat(simpleDatePattern);
    sbf.append("Date: ").append(sdf.format(new Date()));
    sbf.append(LINE_END); // 发送时间
    sbf.append("Content-Type: ");
    sbf.append(contentType);
    sbf.append(";");
    sbf.append("boundary=\"");
    sbf.append(mixedBoundary).append("\""); // 邮件类型设置
    sbf.append(LINE_END);
    // sbf.append(
    // "This is a multi-part message in MIME format."
    // );
    // sbf.append(LINE_END);
    
    // 添加邮件正文单元
    addContent();
    
    // 合并所有单元，正文和附件。
    sbf.append(getAllParts());
    
    // System.out.println(
    // "///////////\n" +
    // sbf.toString() +
    // "///////////////\n");
    
    // 发送
    sbf.append(LINE_END).append(".").append(LINE_END);
    pw.write(sbf.toString());
    readResponse(pw, br, infoBuilder, "354");
    flush(pw);
    
    // QUIT退出
    pw.write("QUIT" + LINE_END);
    if (!readResponse(pw, br, infoBuilder, "250"))
        return infoBuilder.toString();
    flush(pw);
    
    return infoBuilder.toString();
    

    } catch (Exception e) {
    e.printStackTrace();
    return "Exception:>" + e.getMessage();
    } finally {
    // 释放资源
    try {
    if (null != socket)
    socket.close();
    if (null != pw)
    pw.close();
    if (null != br)
    br.close();
    } catch (IOException e) {
    e.printStackTrace();
    }

    // this.to.clear();
    // this.cc.clear();
    // this.bcc.clear();
    this.partSet.clear();
    

    }

  }

  /**

  • 将SMTP命令发送到邮件服务器
  • @param pw
  • 邮件服务器输入流 */ private void flush(PrintWriter pw) { if (!isAllowReadSocketInfo) { pw.flush(); } }

  /**

  • 读取邮件服务器的响应信息
  • @param pw
  • 邮件服务器输入流
  • @param br
  • 邮件服务器输出流
  • @param infoBuilder
  • 用来存放服务器响应信息的字符串缓冲
  • @param msgCode
  • @return
  • @throws IOException */ private boolean readResponse(PrintWriter pw, BufferedReader br, StringBuilder infoBuilder, String msgCode) throws IOException { if (isAllowReadSocketInfo) { pw.flush(); String message = br.readLine(); infoBuilder.append("SERVER:/>"); infoBuilder.append(message).append(LINE_END); if (null == message || 0 > message.indexOf(msgCode)) { System.out.println("ERROR: " + message); pw.write("QUIT".concat(LINE_END)); pw.flush(); return false; } if (isDebug) { System.out.println("DEBUG:/>" + msgCode + "/" + message); } } return true; }

  public String getBoundaryNextPart() {
  return boundaryNextPart;
  }

  public void setBoundaryNextPart(String boundaryNextPart) {
  this.boundaryNextPart = boundaryNextPart;
  }

  public String getDefaultAttachmentContentType() {
  return defaultAttachmentContentType;
  }

  public void setDefaultAttachmentContentType(
  String defaultAttachmentContentType) {
  this.defaultAttachmentContentType = defaultAttachmentContentType;
  }

  public String getHost() {
  return host;
  }

  public void setHost(String host) {
  this.host = host;
  }

  public String getFrom() {
  return from;
  }

  public void setFrom(String from) {
  this.from = from;
  }

  public List getTo() {
  return to;
  }

  public void setTo(List to) {
  this.to = to;
  }

  public String getSubject() {
  return subject;
  }

  public void setSubject(String subject) {
  this.subject = subject;
  }

  public String getUser() {
  return user;
  }

  public void setUser(String user) {
  this.user = user;
  }

  public String getPassword() {
  return password;
  }

  public void setPassword(String password) {
  this.password = password;
  }

  public String getContentType() {
  return contentType;
  }

  public void setContentType(String contentType) {
  this.contentType = contentType;
  }

  public String getBoundary() {
  return boundary;
  }

  public void setBoundary(String boundary) {
  this.boundary = boundary;
  }

  public String getContentTransferEncoding() {
  return contentTransferEncoding;
  }

  public void setContentTransferEncoding(String contentTransferEncoding) {
  this.contentTransferEncoding = contentTransferEncoding;
  }

  public String getCharset() {
  return charset;
  }

  public void setCharset(String charset) {
  this.charset = charset;
  }

  public String getContentDisposition() {
  return contentDisposition;
  }

  public void setContentDisposition(String contentDisposition) {
  this.contentDisposition = contentDisposition;
  }

  public String getSimpleDatePattern() {
  return simpleDatePattern;
  }

  public void setSimpleDatePattern(String simpleDatePattern) {
  this.simpleDatePattern = simpleDatePattern;
  }

  public String getContent() {
  return content;
  }

  /**

  • @param content
  • @deprecated 请参见 {@link #addTextContent(String)} 和
  • {@link #addHtmlContent(String)} */ public void setContent(String content) { this.content = content; }

  public boolean isAllowReadSocketInfo() {
  return isAllowReadSocketInfo;
  }

  public void setAllowReadSocketInfo(boolean isAllowReadSocketInfo) {
  this.isAllowReadSocketInfo = isAllowReadSocketInfo;
  }

  /**

  • @param args
    */
    public static void main(String[] args) {
    // 应用示例：线程化发送邮件
    new Thread() {
    @Override
    public void run() {
    System.out.println("SENDER-" + this.getId() + ":/>"
    + "开始发送邮件...");

        // 创建邮件对象
        Email mail = new Email();
        mail.setHost("smtp.byd.com"); // 邮件服务器地址
        mail.setFrom("[e-mail]"); // 发件人邮箱
        mail.addTo("[e-mail]"); // 收件人邮箱
        mail.addCc("[e-mail]");
        mail.addBcc("");
        mail.setSubject("研发物料邮件发送测试"); // 邮件主题
        mail.setUser("kou.hongtao"); // 用户名
        mail.setPassword("byd@user"); // 密码
    
        // 邮件正文
        mail.addHtmlContent("<h3>研发物料邮件测试，请不要回复！</h3>");
    
       // mail.addAttachment("add.js"); // 添加附件
    
        System.out.println(mail.send()); // 发送
    
        System.out.println("SENDER-" + this.getId() + ":/>"
                + "邮件已发送完毕！");
    }
    

    }.start();

  }
  }

[/code]