将多个文件附加到电子邮件中

Question

我一直在苦苦挣扎了一段时间，找不到解决问题的答案。 该场景如下： 在Google应用引擎中使用了一个使用play framework的Web应用程序。试图将2个pdf文件附加到电子邮件并发送。有了一个文件，它完美地工作。有两个我得到错误。 以下是代码： package app;

import java.io.ByteArrayOutputStream; 
import java.io.File; 
import java.io.FileInputStream; 
import java.io.FileNotFoundException; 
import java.io.IOException; 
import java.io.UnsupportedEncodingException; 
import java.util.Properties; 

import javax.activation.DataHandler; 
import javax.activation.DataSource; 
import javax.activation.MimeType; 
import javax.mail.Message; 
import javax.mail.MessagingException; 
import javax.mail.Multipart; 
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.util.ByteArrayDataSource; 


public class Mailer { 

    public static void sendEmail(String to, String subject, String body, byte[]  pdf1, byte[] pdf2) 
    throws AddressException, MessagingException, UnsupportedEncodingException{ 
     Properties props = new Properties(); 
     Session session = Session.getDefaultInstance(props, null); 
     Message msg = new MimeMessage(session); 
     msg.setFrom(new InternetAddress("myAddress@gmail.com", "John Smith")); 
     msg.addRecipient(Message.RecipientType.TO, new InternetAddress(to, to)); 
     msg.setSubject(subject); 
     msg.setText(body); 

     Multipart mp = new MimeMultipart(); 

     MimeBodyPart htmlPart = new MimeBodyPart(); 
     htmlPart.setContent(body, "text/html"); 
     mp.addBodyPart(htmlPart); 

     //Attaching first pdf 
     MimeBodyPart attachment = new MimeBodyPart(); 
     attachment.setFileName("pdf1.pdf"); 
     DataSource src = new ByteArrayDataSource(pdf1, "application/pdf"); 
     attachment.setDataHandler(new DataHandler(src)); 
     mp.addBodyPart(attachment); 


     //Attaching second pdf 
     attachment = new MimeBodyPart(); 
     attachment.setFileName("pdf2.pdf"); 
     src = new ByteArrayDataSource(badgePDF, "application/pdf"); 
     attachment.setDataHandler(new DataHandler(src)); 
     mp.addBodyPart(attachment); 


     msg.setContent(mp); 

     Transport.send(msg); 
    } 


} 

不幸的是我，即使我打印捕获异常的stackTrack没有错误消息，但我我的猜测是，有与数据源对象的问题。我很感激任何帮助。

Answer 1

对于您的DataSource类型，您应该使用FileDataSource而不是使用ByteArrayDataSource。尝试以下方法：通过应用程序生成

Multipart mp = new MimeMultipart(); 
MimeBodyPart htmlPart = new MimeBodyPart(); 
htmlPart.setContent(body, "text/html"); 
mp.addBodyPart(htmlPart);  

File[] attachments = new File[2]; 
atts[1] = new File("pdf1.pdf"); 
atts[2] = new File("pdf2.pdf"); 
for(int i = 0; i < attachments.length; i++) { 
    messageBodyPart = new MimeBodyPart(); 
    FileDataSource fileDataSource =new FileDataSource(attachments[i]); 
    messageBodyPart.setDataHandler(new DataHandler(fileDataSource)); 
    messageBodyPart.setFileName(attachments[i].getName()); 
    mp.addBodyPart(messageBodyPart); 

} 

msg.setContent(mp); 
Transport.send(msg);