作者/出处：Blueski编译（包含了2篇文章，前篇用了sun.net.smtp，后一篇用了javamail.

一、我们可以通过任何支持sun规范中的sun.net.smtp包的JSP引擎(如JSWDK)发送mail。
(警告:使用内置的internal Sun规范包，这将影响到你的jsp程序的可移植性。)

以下scriptlet利用SmtpClient类在jsp文件中发送email。

<%@ page import="sun.net.smtp.SmtpClient, java.io.*" %>
<%
String from="gseshadri@hotmail.com";
String to="govind@jguru.com, govi@bigfoot.com";
try{
SmtpClient client = new SmtpClient("mail.xxxxx.xxx");
client.from(from);
client.to(to);
PrintStream message = client.startMessage();
message.println("To: " + to);
message.println("Subject: Sending email from JSP!");
message.println("This was sent from a JSP page!");
message.println();
message.println("Cool beans! :-)");
message.println();
message.println("Govind Seshadri");
message.println("jGuru.com");
message.println();
client.closeServer();
}
catch (IOException e){
System.out.println("ERROR SENDING EMAIL:"+e);
}
%>


二、 JavaMail是官方的 Java mail API，可参考 http://java.sun.com/products/javamail/。虽然该API比 sun.net.smtp.SmtpClient更丰富或者说更复杂，但它是可移植的。这里重新创建了一个 MailSender类，它包含了 JavaMail API。如下所示：


// ms_ prefix is for MailSender class variables
// str prefix is for String
// astr prefix is for array of Strings
// strbuf prefix is for StringBuffers, etc.
public MailSender(
String strFrom, // sender
String[] astrTo, // recipient(s)
String[] astrBCC, // bcc recipient(s), optional
String strSubject, // subject
boolean debugging)
{
ms_strFrom = strFrom; // who the message is from
ms_astrTo = astrTo; // who (plural) the message is to
ms_debugging = debugging; // who (plural) the message is to

// set the host
Properties props = new Properties();
props.put("mail.smtp.host", ms_strSMTPHost);

// create some properties and get the default Session
Session session = Session.getDefaultInstance(props, null);
session.setDebug(ms_debugging);

try {
// create a message
ms_msg = new MimeMessage(session);

// set the from
InternetAddress from = new InternetAddress(strFrom);
ms_msg.setFrom(from);

// set the to
InternetAddress[] address = new InternetAddress[astrTo.length];
for (int i = 0; i astrTo.length; ++i)
{
address[i] = new InternetAddress(astrTo[i]);
}
ms_msg.setRecipients(Message.RecipientType.TO, address);

// set the bcc recipients
if (astrBCC != null)
{
address = new InternetAddress[astrBCC.length];
for (int i = 0; i astrBCC.length; ++i)
{
eh.dbg("astrBCC[" + i + "] is: ''" + astrBCC[i] + "''");
address[i] = new InternetAddress(astrBCC[i]);
}
ms_msg.setRecipients(Message.RecipientType.BCC, address);
}

// set the subject
ms_msg.setSubject(strSubject);

// set up the string buffer which will hold the message
ms_strbufMsg = new StringBuffer();

} catch (MessagingException mex) {
mex.printStackTrace(System.err);
} catch (Exception ex) {
ex.printStackTrace(System.err);
}
}

public void ms_add(String strText)
{
ms_strbufMsg.append(strText);
}

public void ms_send()
{
try {
// set the content as plain text
ms_msg.setContent(new String(ms_strbufMsg), "text/plain");

// and away
Transport.send(ms_msg);
} catch (Exception ex) {
System.out.println("Caught exception in MailSender.ms_send: " + ex);
}
}