Need help about "Get Attachment File Name" Tutorial from Java2s.com

i try the tutorial Get Attachment File Name from Java2s.com. What i'm doing is to read email from the Outlook Web Access Light. If i put the url address of the Outlook Web Access Light, i have the error:

Exception in thread "main" javax.mail.NoSuchProviderException: No provider for http
        at javax.mail.Session.getProvider(Session.java:455)
        at javax.mail.Session.getStore(Session.java:530)
        at javax.mail.Session.getFolder(Session.java:602)
        at MainClass.main(MainClass.java:19)
Java Result: 1

I don't understand the line :

("protocol://username@host/foldername");

here is the code:

import java.util.Properties;

import javax.mail.Authenticator;
import javax.mail.Folder;
import javax.mail.Message;
import javax.mail.Part;
import javax.mail.PasswordAuthentication;
import javax.mail.Session;
import javax.mail.URLName;
import javax.mail.internet.InternetAddress;

public class MainClass {

  public static void main(String[] args) throws Exception {
    URLName server = new URLName("protocol://username@host/foldername");

    Session session = Session.getDefaultInstance(new Properties(), new MailAuthenticator());

   开发者_如何学运维 Folder folder = session.getFolder(server);
    if (folder == null) {
      System.out.println("Folder " + server.getFile() + " not found.");
      System.exit(1);
    }
    folder.open(Folder.READ_ONLY);

    Message[] messages = folder.getMessages();
    for (int i = 0; i < messages.length; i++) {
      System.out.println(messages[i].getSize() + " bytes long.");
      System.out.println(messages[i].getLineCount() + " lines.");
      String disposition = messages[i].getDisposition();
      if (disposition == null){
        ; // do nothing
      }else if (disposition.equals(Part.INLINE)) {
        System.out.println("This part should be displayed inline");
      } else if (disposition.equals(Part.ATTACHMENT)) {
        System.out.println("This part is an attachment");
        String fileName = messages[i].getFileName();
        System.out.println("The file name of this attachment is " + fileName);
      }
      String description = messages[i].getDescription();
      if (description != null) {
        System.out.println("The description of this message is " + description);
      }
    }
    folder.close(false);
  }
}

class MailAuthenticator extends Authenticator {

  public MailAuthenticator() {
  }

  public PasswordAuthentication getPasswordAuthentication() {
    return new PasswordAuthentication("username", "password");
  }
}

Thank you for your support have a nice day

Given the error message I really think javaMail is expecting for protocol one of "smtp:" or "imap:" or "pop3:", because it is the way it constructs its session. I don't think it will ever work with a web access, you have to get the address of the pop3/imp/smtp server the web interface connects to.

I'm not sure but "protocol://username@host/foldername" seems to describe a format rather than a real url, i.e. it tells you to add a protocol, a user name, a host and a folder like "http://Thomas@stackoverflow.com/need-help-about-get-attachment-file-name-tutorial-from-java2s-com" (just an example of how it might look like, this particular url is not likely to work/exist/whatever :) ).