想知道java是怎么实现发邮件的吗？请看详细的代码和说明！
package mail;
import java.io.File;
import java.io.UnsupportedEncodingException;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
import java.util.Date;
import java.util.Properties;
import javax.activation.DataHandler;
import javax.activation.FileDataSource;
import javax.mail.Address;
import javax.mail.MessagingException;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.AddressException;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeBodyPart;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMultipart;
import javax.mail.internet.MimeUtility;
public class Mail {
/** 发件方式 - 普通发送 */
final public static int TO = 0;
/** 发件方式 - 抄送 */
final public static int CC = 1;
/** 发件方式 - 密件抄送 */
final public static int BCC = 2;
/** 邮件相关信息 - SMTP 服务器 */
private String mailSMTPHost = null;
/** 邮件相关信息 - 邮件用户名 */
private String mailUser = null;
/** 邮件相关信息 - 密码 */
private String mailPassword = null;
/** 邮件相关信息 - 发件人邮件地址 */
private String mailFromAddress = null;
/** 邮件相关信息 - 邮件主题 */
private String mailSubject = "";
/** 邮件相关信息 - 邮件发送地址 */
private Address[] mailTOAddress = null;
/** 邮件相关信息 - 邮件抄送地址 */
private Address[] mailCCAddress = null;
/** 邮件相关信息 - 邮件密件抄送地址 */
private Address[] mailBCCAddress = null;
/** 邮件相关信息 - 邮件正文(复合结构) */
private MimeMultipart mailBody = null;
public Mail() {
mailBody = new MimeMultipart();
}
/**
* 设置 SMTP 服务器
* @param strSMTPHost 邮件服务器名称或 IP
* @param strUser 邮件用户名
* @param strPassword 密码
*/
public void setSMTPHost(String strSMTPHost, String strUser,
String strPassword) {
this.mailSMTPHost = strSMTPHost;
this.mailUser = strUser;
this.mailPassword = strPassword;
}
/**
* 设置邮件发送地址
* @param strFromAddress 邮件发送地址
*/
public void setFromAddress(String strFromAddress) {
this.mailFromAddress = strFromAddress;
}
/**
* 设置邮件目的地址
* @param strAddress 邮件目的地址列表, 不同的地址可用;号分隔
* @param iAddressType 邮件发送方式 (TO 0, CC 1, BCC 2) 常量已在本类定义
* @throws AddressException
*/
public void setAddress(String strAddress, int iAddressType) throws
AddressException {
switch (iAddressType) {
case Mail.TO: {
ArrayList alAddress = StringHelper.split(strAddress, ';');
mailTOAddress = new Address[alAddress.size()];
for (int i = 0; i < alAddress.size(); i++) {
mailTOAddress[i] = new InternetAddress( (String) alAddress.get(i));
}
break;
}
case Mail.CC: {
ArrayList alAddress = StringHelper.split(strAddress, ';');
mailCCAddress = new Address[alAddress.size()];
for (int i = 0; i < alAddress.size(); i++) {
mailCCAddress[i] = new InternetAddress( (String) alAddress.get(i));
}
break;
}
case Mail.BCC: {
ArrayList alAddress = StringHelper.split(strAddress, ';');
mailBCCAddress = new Address[alAddress.size()];
for (int i = 0; i < alAddress.size(); i++) {
mailBCCAddress[i] = new InternetAddress( (String) alAddress.get(i));
}
break;
}
}
}
/**
* 设置邮件主题
* @param strSubject 邮件主题
*/
public void setSubject(String strSubject) {
this.mailSubject = strSubject;
}
/**
* 设置邮件文本正文
* @param strTextBody 邮件文本正文
* @throws MessagingException
*/
public void setTextBody(String strTextBody) throws MessagingException {
MimeBodyPart mimebodypart = new MimeBodyPart();
mimebodypart.setText(strTextBody, "GBK");
mailBody.addBodyPart(mimebodypart);
}
/**
* 设置邮件超文本正文
* @param strHtmlBody 邮件超文本正文
* @throws MessagingException
*/
public void setHtmlBody(String strHtmlBody) throws MessagingException {
MimeBodyPart mimebodypart = new MimeBodyPart();
mimebodypart.setDataHandler(new DataHandler(strHtmlBody, "text/html;charset=GBK"));
mailBody.addBodyPart(mimebodypart);
}
/**
* 设置邮件正文外部链接 URL, 信体中将包含链接所指向的内容
* @param strURLAttachment 邮件正文外部链接 URL
* @throws MessagingException
* @throws MalformedURLException
*/
public void setURLAttachment(String strURLAttachment) throws
MessagingException, MalformedURLException {
MimeBodyPart mimebodypart = new MimeBodyPart();
mimebodypart.setDataHandler(new DataHandler(new URL(strURLAttachment)));
mailBody.addBodyPart(mimebodypart);
}
/**
* 设置邮件附件
* @param strFileAttachment 文件的全路径
* @throws MessagingException
* @throws UnsupportedEncodingException
*/
public void setFileAttachment(String strFileAttachment) throws
MessagingException, UnsupportedEncodingException {
File path = new File(strFileAttachment);
if (!path.exists() || path.isDirectory()) {
return;
}
String strFileName = path.getName();
MimeBodyPart mimebodypart = new MimeBodyPart();
mimebodypart.setDataHandler(new DataHandler(new FileDataSource(
strFileAttachment)));
// modified by zord @ 2003/6/16 to support Chinese File Name
// mimebodypart.setFileName(strFileName);
mimebodypart.setFileName(MimeUtility.encodeText(strFileName));
// end of modify
mailBody.addBodyPart(mimebodypart);
}
/**
* 邮件发送(一次发送多个地址, 优点速度快, 但是有非法邮件地址时将中断发送操作)
* @throws MessagingException
*/
public void sendBatch() throws MessagingException {
Properties properties = new Properties();
properties.put("mail.smtp.host", this.mailSMTPHost);
Session session = Session.getInstance(properties, null);
MimeMessage mimemessage = new MimeMessage(session);
mimemessage.setFrom(new InternetAddress(this.mailFromAddress));
if (mailTOAddress != null) {
mimemessage.addRecipients(javax.mail.Message.RecipientType.TO,
this.mailTOAddress);
}
if (mailCCAddress != null) {
mimemessage.addRecipients(javax.mail.Message.RecipientType.CC,
this.mailCCAddress);
}
if (mailBCCAddress != null) {
mimemessage.addRecipients(javax.mail.Message.RecipientType.BCC,
this.mailBCCAddress);
}
mimemessage.setSubject(this.mailSubject);
mimemessage.setContent(this.mailBody);
mimemessage.setSentDate(new Date());
Transport transport = session.getTransport("smtp");
transport.connect(this.mailSMTPHost, this.mailUser, this.mailPassword);
Transport.send(mimemessage);
System.out.println("已向下列邮箱发送了邮件");
if (mailTOAddress != null) {
for (int i = 0; i < mailTOAddress.length; i++) {
System.out.println(mailTOAddress[i]);
}
}
if (mailCCAddress != null) {
for (int i = 0; i < mailTOAddress.length; i++) {
System.out.println(mailCCAddress[i]);
}
}
if (mailBCCAddress != null) {
for (int i = 0; i < mailTOAddress.length; i++) {
System.out.println(mailBCCAddress[i]);
}
}
}
static public void main(String str[]) throws MessagingException
{
Mail mail=new Mail();
mail.setAddress("jgls@21cn.com",Mail.TO);
mail.setFromAddress("jgls@21cn.com");
mail.setSMTPHost("mail.21cn.com","","");
mail.setSubject("测试一下");
mail.setHtmlBody("");
mail.sendBatch();
}
}
补充说明：
StringHelper.split函数
public static ArrayList spilt(String fieldsru, String tag)
{
int begin = 0;
int end;
char dot = tag.charAt(0);
String field;
field = fieldsru + dot;
int num = 0;
int field_len = field.length();
for (int i = 0; i < field_len; i++)
{
if (field.charAt(i) == dot)
{
num++;
}
}
ArrayList returnarray = new ArrayList();
for (int j = 0; j < num; j++)
{
end = field.indexOf(dot, begin);
returnarray.add(field.substring(begin, end));
begin = end + 1;
}
return returnarray;
}
关于使用javamail包发送邮件时编码的解决问题：
1. 在发送正文时指定正文编码：
在发送邮件时使用
MimeBodyPart body = new MimeBodyPart();
body.setContent(content, "text/html;charset=GB2312");
注意此时的content编码必须是所指定的编码格式。
2. 在设置邮件标题时也要指定标题的编码：
MimeMultipart mmp=new MimeMultipart();
mmp.setSubject(subject, "GB2312");
同上也要求subject的编码和指定的编码一致。
3. 发送正文时也可以在header中指定传输编码：
body.setHeader("Content-Transfer-Encoding", "base64"); // 指定使用base64编码
