通过TLS发送的Java邮件

抽象

本博客的目的是演示如何使用Java Mail通过具有TLS连接的SMTP服务器发送电子邮件。

免责声明

这篇文章仅供参考。在使用所提供的任何信息之前，请认真思考。从中学到东西，但最终自己做出决定，风险自负。

要求

我使用以下主要技术完成了本文的所有工作。您可能可以使用不同的技术或版本来做相同的事情，但不能保证。

NetBeans 11.2
Maven 3.3.9（与NetBeans捆绑在一起）
Java 11（zulu11.35.15-ca-jdk11.0.5-win_x64）

 <dependency> <groupId>javax.mail</groupId> <artifactId>mail</artifactId> <version> 1.4 </version> <scope>test</scope>  </dependency>

下载

访问我的GitHub页面https://github.com/mjremijan以查看我所有的开源项目。这篇文章的代码位于thoth-email-via-tls模块中的https://github.com/mjremijan/thoth-email 。

物产

本示例使用smtp-tls-outlook.properties文件保存SMTP服务器信息。我用我个人的Outlook帐户进行测试，因此使用这个词的outlook属性文件中的名称。重要的是文件的内容，如清单1所示。

清单1 –属性文件

 # This is the name of the SMTP host machine.  host=  # This is the port number of the SMTP host machine.  # The same host may support both SSL and TLS but on  # different ports. So make sure you get the TLS port.  port=  # This is what you use in the “username” field when  # you login. Typically # you login. Typically this is the same as your email  # address, but this isn't always the case .  username=  # This is what you use in the “password” field when  # you login. This value is CLEAR TEXT, so keep # you login. This value is CLEAR TEXT, so keep this  # properties file safe.  password=  # This is the email address you want for the  # email's FROM field. Enter the value using  # the format shown below. Typically # the format shown below. Typically this is  # just your email address for the account.  from=FIRSTNAME LASTNAME <ADDRESS @EMAIL .COM>  # This is the email address you want for the  # email's REPLY_TO field. Enter the value using  # the format shown below. Typically # the format shown below. Typically this is  # just your email address for the account. Also the account. Also  # typically this is the same as `from` above.  # But be warned, if an email's FROM and REPLY_TO  # are different, that's may be flagged as spam  # and never be delivered. So keep `from` and  # `reply` the same for initial testing  reply=FIRSTNAME LASTNAME <ADDRESS @EMAIL .COM>  # This is the email address you want to send  # the email to. For testing, it's a good idea  # to send it to yourself first.  to=FIRSTNAME LASTNAME <ADDRESS @EMAIL .COM>

现在您有了属性文件，接下来让我们看一下代码。

码

这是一个JUnit测试，演示了如何使用Java Mail通过具有TLS连接的SMTP服务器发送电子邮件。清单2显示了代码。

注意对于初始测试，请始终检查您的SPAM文件夹。可以始终添加一条规则以将其传送到您的INBOX。

清单2 – Java Mail示例

 package org.thoth.email.via.tls;  import java.net.InetAddress;  import java.text.SimpleDateFormat;  import java.util.Date;  import java.util.Properties;  import javax.mail.Authenticator;  import javax.mail.Message;  import javax.mail.PasswordAuthentication;  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;  import org.junit.jupiter.api.BeforeEach;  import org.junit.jupiter.api.Test;  public class TlsTest { public TlsTest() { } String now, hostname; protected String now, hostname; protected Properties outlook; @BeforeEach public void setUp() throws Exception { now = new SimpleDateFormat( "MM-dd-yyyy hh:mm:ss a" ).format( new Date()); hostname = InetAddress.getLocalHost().getHostName(); outlook = new Properties(); outlook.load( this .getClass().getResourceAsStream( "/smtp-tls-outlook.properties" )); } @Test public void a_test() throws Exception { // Create MimeMultipart MimeMultipart content = new MimeMultipart( "related" ); // html part { MimeBodyPart textPart = new MimeBodyPart(); textPart.setText( "<html><body>" + "<p>Time: " +now+ "</p>" + "<p>From: " +hostname+ "</p>" + "</body></html>" , "UTF8" , "html" ); content.addBodyPart(textPart); } // properties Properties props = new Properties(); { props.setProperty( "mail.smtp.auth" , "true" ); props.setProperty( "mail.smtp.host" , outlook.getProperty( "host" )); props.setProperty( "mail.smtp.port" , outlook.getProperty( "port" )); props.setProperty( "mail.smtp.starttls.enable" , "true" ); } Session smtp = null ; { smtp = Session.getInstance(props, new Authenticator() { @Override protected PasswordAuthentication getPasswordAuthentication() { return new PasswordAuthentication( outlook.getProperty( "username" ) , outlook.getProperty( "password" ) ); } }); smtp.setDebug( true ); smtp.setDebugOut(System.out); } MimeMessage m = new MimeMessage(smtp); { m.setRecipient(Message.RecipientType.TO, new InternetAddress(outlook.getProperty( "to" ))); m.setSubject( "thoth-email TLS test " + now); InternetAddress from = null ; { from = new InternetAddress(outlook.getProperty( "from" )); from.setPersonal( "Thoth Email" ); m.setFrom(from); } InternetAddress reply = null ; { reply = new InternetAddress(outlook.getProperty( "reply" )); m.setReplyTo( new InternetAddress[] {reply}); } m.setContent(content); } Transport.send(m); }  }