JavaMail发送邮件实例——给多人发送、抄送

JavaMail，顾名思义，提供给开发者处理电子邮件相关的编程接口。它是Sun发布的用来处理email的API。它可以方便地执行一些常用的邮件传输。我们可以基于JavaMail开发出类似于Microsoft
Outlook的应用程序。

虽然JavaMail是Sun的API之一，但它目前还没有被加在标准的java开发工具包中（Java Development Kit），这就意味着你在使用前必须另外下载JavaMail文件。

JavaMail包中用于处理电子邮件的核心类是：Session,Message,Address,Authenticator,Transport,Store,Folder等。Session定义了一个基本的邮件会话，它需要从Properties中读取类似于邮件服务器，用户名和密码等信息。

关键技术：

1、MimeMessage的setRecipients方法设置邮件的收件人，其中Message.RecipientType.TO常量表示收件人类型是邮件接收者，Message.RecipientType.CC常量表示收件人类型是抄送者，Message.RecipientType.BCC常量表示收件人的类型是密送着。

2、在调用MimeMessage的setRecipients方法时，除了可以指定收件人的类型外，还可以传入一个数组，指定多个收件人的地址。

import javax.mail.Address;
import javax.mail.BodyPart;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.Multipart;
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;

public class MultiMailsender {

/**
* 发送邮件给多个接收者
* @param mailInfo    带发送邮件的信息
* @return
*/
public static boolean sendMailtoMultiReceiver(MultiMailSenderInfo mailInfo){
MyAuthenticator authenticator = null;
if (mailInfo.isValidate()) {
authenticator = new MyAuthenticator(mailInfo.getUserName(),
mailInfo.getPassword());
}
Session sendMailSession = Session.getInstance(mailInfo
.getProperties(), authenticator);
try {
Message mailMessage = new MimeMessage(sendMailSession);
// 创建邮件发送者地址
Address from = new InternetAddress(mailInfo.getFromAddress());
mailMessage.setFrom(from);
// 创建邮件的接收者地址，并设置到邮件消息中
Address[] tos = null;
String[] receivers = mailInfo.getReceivers();
if (receivers != null){
// 为每个邮件接收者创建一个地址
tos = new InternetAddress[receivers.length + 1];
tos[0] = new InternetAddress(mailInfo.getToAddress());
for (int i=0; i<receivers.length; i++){
tos[i+1] = new InternetAddress(receivers[i]);
}
} else {
tos = new InternetAddress[1];
tos[0] = new InternetAddress(mailInfo.getToAddress());
}
// 将所有接收者地址都添加到邮件接收者属性中
mailMessage.setRecipients(Message.RecipientType.TO, tos);

mailMessage.setSubject(mailInfo.getSubject());
mailMessage.setSentDate(new Date());
// 设置邮件内容
Multipart mainPart = new MimeMultipart();
BodyPart html = new MimeBodyPart();
html.setContent(mailInfo.getContent(), "text/html; charset=GBK");
mainPart.addBodyPart(html);
mailMessage.setContent(mainPart);
// 发送邮件
Transport.send(mailMessage);
return true;
} catch (MessagingException ex) {
ex.printStackTrace();
}
return false;
}

/**
* 发送带抄送的邮件
* @param mailInfo    待发送邮件的消息
* @return
*/
public static boolean sendMailtoMultiCC(MultiMailSenderInfo mailInfo){
MyAuthenticator authenticator = null;
if (mailInfo.isValidate()) {
authenticator = new MyAuthenticator(mailInfo.getUserName(),
mailInfo.getPassword());
}
Session sendMailSession = Session.getInstance(mailInfo
.getProperties(), authenticator);
try {
Message mailMessage = new MimeMessage(sendMailSession);
// 创建邮件发送者地址
Address from = new InternetAddress(mailInfo.getFromAddress());
mailMessage.setFrom(from);
// 创建邮件的接收者地址，并设置到邮件消息中
Address to = new InternetAddress(mailInfo.getToAddress());
mailMessage.setRecipient(Message.RecipientType.TO, to);

// 获取抄送者信息
String[] ccs = mailInfo.getCcs();
if (ccs != null){
// 为每个邮件接收者创建一个地址
Address[] ccAdresses = new InternetAddress[ccs.length];
for (int i=0; i<ccs.length; i++){
ccAdresses[i] = new InternetAddress(ccs[i]);
}
// 将抄送者信息设置到邮件信息中，注意类型为Message.RecipientType.CC
mailMessage.setRecipients(Message.RecipientType.CC, ccAdresses);
}

mailMessage.setSubject(mailInfo.getSubject());
mailMessage.setSentDate(new Date());
// 设置邮件内容
Multipart mainPart = new MimeMultipart();
BodyPart html = new MimeBodyPart();
html.setContent(mailInfo.getContent(), "text/html; charset=GBK");
mainPart.addBodyPart(html);
mailMessage.setContent(mainPart);
// 发送邮件
Transport.send(mailMessage);
return true;
} catch (MessagingException ex) {
ex.printStackTrace();
}
return false;
}

public static void main(String[] args) {
// 创建邮件信息
MultiMailSenderInfo mailInfo = new MultiMailSenderInfo();
mailInfo.setMailServerHost("smtp.sina.com.cn");
mailInfo.setMailServerPort("25");
mailInfo.setValidate(true);
mailInfo.setUserName("***");
mailInfo.setPassword("***");
mailInfo.setFromAddress("***@sina.com");
mailInfo.setToAddress("***@163.com");
mailInfo.setSubject("MyMail测试");
mailInfo.setContent("我的邮件测试/n/rMy test mail/n/r");

String[] receivers = new String[]{"***@163.com", "***@tom.com"};
String[] ccs = receivers;
mailInfo.setReceivers(receivers);
mailInfo.setCcs(ccs);

MultiMailsender.sendMailtoMultiReceiver(mailInfo);
MultiMailsender.sendMailtoMultiCC(mailInfo);
}

/**
* 发送多接收者类型邮件的基本信息
*/
public static class MultiMailSenderInfo extends MailSenderInfo{
// 邮件的接收者，可以有多个
private String[] receivers;
// 邮件的抄送者，可以有多个
private String[] ccs;

public String[] getCcs() {
return ccs;
}
public void setCcs(String[] ccs) {
this.ccs = ccs;
}
public String[] getReceivers() {
return receivers;
}
public void setReceivers(String[] receivers) {
this.receivers = receivers;
}
}
}