Android开发中，当忘记密码需要找回密码的时候，很多情况都是向注册邮箱自动发送注册登录密码，自己写的一个自动发送邮件的java类，亲测可用。

直接贴代码：

    public class SendMail {  
      
        static int port = 25;//端口号  
        static String server = "smtp.163.com";// 邮件服务器mail.cpip.net.cn  
        static String from = "小明";// 发送者,显示的发件人名字  
        static String user = "xxxxx@163.com";// 发送者邮箱地址  
        static String password = "xxxxxx";// 密码  
      
        public static void sendEmail(String email, String subject, String body)  
                throws UnsupportedEncodingException {  
            try {  
                Properties props = new Properties();  
                props.put("mail.smtp.host", server);  
                props.put("mail.smtp.port", String.valueOf(port));  
                props.put("mail.smtp.auth", "true");  
                Transport transport = null;  
                Session session = Session.getDefaultInstance(props, null);  
                transport = session.getTransport("smtp");  
                transport.connect(server, user, password);  
                MimeMessage msg = new MimeMessage(session);  
                msg.setSentDate(new Date());  
                InternetAddress fromAddress = new InternetAddress(user, from,  
                        "UTF-8");  
                msg.setFrom(fromAddress);  
                InternetAddress[] toAddress = new InternetAddress[1];  
                toAddress[0] = new InternetAddress(email);  
                msg.setRecipients(Message.RecipientType.TO, toAddress);  
                msg.setSubject(subject, "UTF-8");  
                msg.setText(body, "UTF-8");  
                msg.saveChanges();  
                transport.sendMessage(msg, msg.getAllRecipients());  
            } catch (NoSuchProviderException e) {  
                e.printStackTrace();  
            } catch (MessagingException e) {  
                e.printStackTrace();  
            }  
        }  
    }