通过smtp使用java代码发送电子邮件

Question

下面是错误和超时异常。

输入代码：

Properties props = new Properties();  
props.put("mail.smtp.auth", "true");
props.put("mail.smtp.starttls.enable", "true");
props.put("mail.smtp.host","smtp.gmail.com"); 
props.put("mail.smtp.port", "587");
props.put("mail.debug", "true");

调试SMTP：正在尝试连接到主机“SMTP.gmail.com”，端口587，isSSL true Exceptioninthread“main”java。lang.RuntimeException:com。太阳邮政util。MailConnectException:无法连接到主机，端口：smtp。gmail。com，587；超时-1。

Answer 1

忽略大多数其他错误或不相关的答案和评论。其中许多包括这些常见的JavaMail错误。您的原始代码很好。

有关GMail的说明，请参阅JavaMail常见问题解答。

你很可能无法连接，因为有防火墙阻止直接访问。JavaMail常见问题解答提供了连接调试技巧。

如果您不能直接连接并需要通过代理服务器连接，JavaMail常见问题解答也会涵盖这一点。

Answer 2

private static void sendFromGMail(String from, String pass, String[] to, String subject, String body) {
    Properties props = System.getProperties();
    String host = "smtp.gmail.com";
  //String host="localhost";
  //props.put("mail.smtp.ssl.trust", "smtp.gmail.com");
    props.put("mail.smtp.starttls.enable", "true");
  //props.put("mail.smtp.host", host);
    props.put("mail.smtp.ssl.trust", host);
    props.put("mail.smtp.user", from);
    props.put("mail.smtp.password", pass);
    props.put("mail.smtp.port", "587");//587
    props.put("mail.smtp.auth", "true");
  //System.out.println("1");

    Session session = Session.getDefaultInstance(props);
    MimeMessage message = new MimeMessage(session);

    try {
         //System.out.println("2");

        message.setFrom(new InternetAddress(from));
        InternetAddress[] toAddress = new InternetAddress[to.length];

        // To get the array of addresses
        for( int i = 0; i < to.length; i++ ) {
            toAddress[i] = new InternetAddress(to[i]);
        }

        for( int i = 0; i < toAddress.length; i++) {
            message.addRecipient(Message.RecipientType.TO, toAddress[i]);
        }

         //System.out.println("3");

        message.setSubject(subject);
        message.setText(body);
        // System.out.println("4");

        Transport transport = session.getTransport("smtp");
        // System.out.println("5");

        transport.connect(host, from, pass);
        transport.sendMessage(message, message.getAllRecipients());
        transport.close();
        //System.out.println("sent successfully...");
    }
    catch (AddressException ae) {
        ae.printStackTrace();
    }
    catch (MessagingException me) {
        me.printStackTrace();
    }
  }

调用上述方法并将这些参数传递给该方法

private static String USER_NAME = "xxxx";  // username "@gmail.com")
private static String PASSWORD = "xxxx"; // password
private static String RECIPIENT = "[e-mail]";

public static void main(String[] args) {
    String from = USER_NAME;
    String pass = PASSWORD;
    String[] to = { RECIPIENT }; // list of recipient email addresses
    String subject = "Java send mail example";
    String body = "Welcome to JavaMail!";

    sendFromGMail(from, pass, to, subject, body);
}

我使用了以下jar文件，

java-mail-1.4.4
javamail-smtp-1.4.2
pop3
mail-6.0.0-sources