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om C Si nh Vi en Zo ne Java Training Introduction to Java Mail SinhVienZone.com https://fb.com/sinhvienzonevn What is JavaMail? -1 JavaMail is an API for sending and receiving email using Java The current version is 1.3.1 and can be downloaded from Sun's website at: ne C om „ nh Vi en Possible uses: „ Send email from web pages using servlets „ Create a GUI email client „ Send email from Java stored procedures „ Send email from any type of Java application „ Spam your friends and enemies! (read email addresses from a database, write a for () loop, and away the emails go!) Si „ Zo http://java.sun.com/products/javamail/ SinhVienZone.com https://fb.com/sinhvienzonevn What is JavaMail? -2 om To send JavaMail, you'll need to add at least two JAR files from Sun to your classpath (placing them in a lib directory may be a good idea) „ activation.jar „ mail.jar nh Vi en Zo ne C „ (Note: You can download these files from the Java Zone) For more complex emailing tasks (like receiving or managing pop3 or imap mail servers), you'll need to download additional files like pop3.jar and imap.jar You will also need access to a mail server and possibly a username/password for that mail server Si „ „ SinhVienZone.com https://fb.com/sinhvienzonevn .C ne Zo nh Vi en „ In general, each internet domain has an email server When you send out an email „ Your email client program sends the message to your email server „ Your email server contacts the addressee's email server using the SMTP (simple mail transfer protocol) „ Your email server verifies that the addressee's user name is valid „ Your email server then transfers the email to the addressee's email server „ When the addressee logs into his email server (using his email client program), he gets his email Si „ om How Does Email Work? SinhVienZone.com https://fb.com/sinhvienzonevn nh Vi en Zo ne C sendmail is the most commonly used mail server in the world, as it generally comes free with Unix and Linux installations „ very powerful and flexible Supports POP3 and IMAP „ well documented (lots of books on setting up sendmail) „ long track record (first version appeared in early '80s) „ tedious to set up (lots of cryptic configuration files) „ free „ www.sendmail.org Si „ om Mail Servers (sendmail)-1 SinhVienZone.com https://fb.com/sinhvienzonevn nh Vi en Zo ne C qmail is probably the most popular alternative to sendmail in the UNIX world „ perhaps more secure than sendmail (at least older versions of sendmail) „ Easier to set up and administer than sendmail „ pretty good documentation (several books written on qmail in the past few years) „ free „ http://www.qmail.org/top.html Si „ om Mail Servers (qmail)-2 SinhVienZone.com https://fb.com/sinhvienzonevn Mail Servers (MS Exchange)-2 MS Exchange is widely used in the Windows world, especially in corporate environments that use MS Office (and hence MS Outlook) „ Expensive „ Integrated into MS Active Directory „ GUI administration tools are easier to learn for Windows people „ MS Outlook is a powerful and slick email program that will work with Exchange, sendmail, or qmail It does, however, have a history of security vulnerabilities and some organizations refuse to use it because of that Si nh Vi en Zo ne C om „ SinhVienZone.com https://fb.com/sinhvienzonevn nh Vi en Zo Currently, the most popular protocols are „ POP3 (Post Office Protocol, version 3) „ IMAP (Internet Message Access Protocol) „ MAPI (Messaging Application Programming Interface-Microsoft Windows email interface) Si „ ne C om POP3, IMAP, MAPI -1 SinhVienZone.com https://fb.com/sinhvienzonevn POP3 nh Vi en Zo ne C om POP3 is the oldest and most widely used It was designed to support offline mail processing „ Mail is delivered to a server and a user's computer runs a mail client program to download any new mail „ Once messages are delivered, they are generally deleted from the mail server „ This minimizes disk space requirements for mail server, but ties the mail to a particular machine If user goes to another computer, he can't access his mail „ POP3 has limited support for reading mail online (and leaving the mail on the mail server) „ Simpler protocol than IMAP makes it easier to implement More POP3 mail clients available Si „ SinhVienZone.com https://fb.com/sinhvienzonevn nh Vi en Zo ne C IMAP „ Developed at University of Washington „ Primarily used to access mail and leave it on the mail server This allows users to access their mail from any computer „ Requires more disk space to store email messages „ Can work in "offline" mode like POP3 „ Easy to manage multiple mailboxes „ Supports tagging emails with flags like "read", "deleted", "answered", etc Si „ om IMAP SinhVienZone.com https://fb.com/sinhvienzonevn Si „ nh Vi en Zo „ C „ Apache has a free mail server called James Supports POP3, SMTP, and NNTP Download the binary file „ ZIP version (for Windows) „ TAR version (for Linux) Uncompress it and then run “run.bat” (Windows) or “run.sh” (Linux) to start the mail server ne „ om Apache James Mail Server Download from here: http://james.apache.org/download.cgi SinhVienZone.com https://fb.com/sinhvienzonevn om NOAA Mail Server You can use ESRL/NOAA’s email server email.boulder.noaa.gov C „ nh Vi en „ This will work IF you send emails to @noaa.gov email addresses (like jeff.s.smith@noaa.gov) When I tried to send an email to jeffssmith1@yahoo.com I got this error message Si „ Zo ne mailProperties.setProperty("mail.smtp.host","email.boulder.noaa.gov"); Invalid Address Relaying not allowed: jeffssmith1@yahoo.com SinhVienZone.com https://fb.com/sinhvienzonevn Once you have a mail server you can use (either James or another mail server), you can send emails through it by using JavaMail In general, to send a plain text email using JavaMail, you the following: „ Get a mail session instance „ Create a MimeMessage object (passing in the mail session instance into the constructor) „ Set the MimeMessage object's properties (like the toAddress, fromAddress, message, etc.) „ Send the message Zo nh Vi en Si „ ne C „ om Using JavaMail -1 SinhVienZone.com https://fb.com/sinhvienzonevn Getting a Mail Session om C nh Vi en „ ne „ Get a mail session for the James mail server If James is running on your own computer, your mail.smtp.host is localhost If your mail server is a remote computer, it might be something like “mailgate.fsl.noaa.gov” Get a mail session for the James mail server Zo „ Si private Session getMailSession() throws Exception { Properties mailProperties = new Properties(); mailProperties.setProperty("mail.transport.protocol", "smtp"); mailProperties.setProperty("mail.smtp.host", "localhost"); return Session.getInstance(mailProperties, null); } SinhVienZone.com https://fb.com/sinhvienzonevn Next, send your email using the mail session C „ om Plain Text Email Example Si nh Vi en Zo ne MimeMessage msg = new MimeMessage(getMailSession()); msg.setFrom(new InternetAddress("bill.gates@msn.com")); msg.addRecipient(Message.RecipientType.TO, new InternetAddress("larry.ellison@oracle.com")); msg.setSubject("RE: Oracle vs SQL Server"); msg.setText("SQL Server is better than Oracle"); Transport.send(msg); SinhVienZone.com https://fb.com/sinhvienzonevn om Exceptions and imports Your code which sends an email will need to catch the following checked exceptions: „ Exception „ MessagingException „ AddressException „ You should import the following packages: Si nh Vi en Zo ne C „ import javax.mail.*; import javax.mail.internet.*; SinhVienZone.com https://fb.com/sinhvienzonevn Zo ne You can also send HTML email with JavaMail HTML email can be used to Use different size fonts „ imbed images into your email „ Use different colored text, bold, italic, etc nh Vi en „ Si „ C om HTML Email SinhVienZone.com https://fb.com/sinhvienzonevn nh Vi en With HTML email, „ you set the mime message content type to "text/html" „ call the setContent() method to set your html content „ It helps to know a little HTML! Si „ Zo ne C om HTML Email SinhVienZone.com https://fb.com/sinhvienzonevn .C Si „ nh Vi en Zo „ Virtually all mail servers require a username and password to receive email Some mail servers require a username and password to send an email (by default, James does not) „ This prevents spammers from hijacking the mail server to send unauthorized email JavaMail supports this username/password authorization and authentication „ To implement this, you get a transport object from the mail session and call the connect() method with the mail host, username, and password „ See next slide for code example ne „ om Mail Security SinhVienZone.com https://fb.com/sinhvienzonevn HTML Email Example Example of sending html message with an imbedded image using username/password authorization om „ Si nh Vi en Zo ne C MimeMessage msg = new MimeMessage(mailSession); msg.setFrom(new InternetAddress("bill@msn.com")); msg.addRecipient(Message.RecipientType.TO, new InternetAddress(“tom@msn.com")); msg.setSubject(subject); String html = "MY SPAM "; msg.setContent(html, "text/html"); Transport transport = mailSession.getTransport("smtp"); transport.connect("localhost","user", "passwd"); msg.saveChanges(); transport.sendMessage(msg, msg.getAllRecipients()); transport.close(); SinhVienZone.com https://fb.com/sinhvienzonevn Email attachments -1 om To append an email attachment, you need to send a "multipart" message „ Create your MimeMessage object as usual, setting the from address, to address, subject, etc „ Create a MimeBodyPart object for your main message and set its text (or content) to be your message „ Create a MimeMultiPart object for your attachment and call its setContent() method to attach your file „ Create a Multipart object and add both body parts to it „ Call your MimeMessage's setContent() method, passing in your Multipart object „ Call Transport.send() to send the message Whew!!! Si nh Vi en Zo ne C „ „ SinhVienZone.com https://fb.com/sinhvienzonevn om Email attachment Example-1 nh Vi en Zo ne C MimeMessage msg = new MimeMessage(getMailSession()); msg.setFrom(new InternetAddress("bill.gates@msn.com")); msg.addRecipient(Message.RecipientType.TO, new InternetAddress("larry.ellison@oracle.com")); msg.setSubject("RE: Oracle vs SQL Server"); Si //Create the main message (body) part MimeBodyPart mainBodyPart = new MimeBodyPart(); mainBodyPart.setText("Here is my message"); SinhVienZone.com https://fb.com/sinhvienzonevn Email attachment Example-2 Zo ne C om //Create attachment body part MimeBodyPart attachBodyPart = new MimeBodyPart(); DataSource source = new FileDataSource("1.jpg"); attachBodyPart.setDataHandler(new DataHandler(source)); attachBodyPart.setFileName("1.jpg"); Si nh Vi en //Now create the multipart and add the parts Multipart multipart = new MimeMultipart(); multipart.addBodyPart(mainBodyPart); multipart.addBodyPart(attachBodyPart); //add the multipart to the original Mime message msg.setContent(multipart); Transport.send(msg); SinhVienZone.com https://fb.com/sinhvienzonevn „ C Si nh Vi en „ ne „ Write a program in package gov.noaa.email that reads a list of email recipients from a disk file and then sends them each an email message Use your NOAA webmail account to test this (or you can use our Yahoo email account) You'll need to: „ Create a file and populate it with a list of email addresses (use your own email address or someone else in the class) „ Send a single email to all the recipients you read from the db table „ If you are feeling ambitious, you can send an HTML email message „ Use an email client (NOAA webmail?) to verify message delivery Extra credit: send an email attachment and write an Ant script for your project Zo „ om Exercise -1 SinhVienZone.com https://fb.com/sinhvienzonevn JavaMail Summary om nh Vi en „ Zo ne „ JavaMail is powerful with good support for things like HTML and attachments But adding an attachment isn't as simple as it should be A nice framework (or helper class) would be useful to simplify JavaMail code JavaMail also supports „ receiving email „ administering mail servers C „ Si For an article on receiving email via JavaMail, see: http://www.javaworld.com/javaworld/jw-10-2001/jw-1026javamail-p2.html SinhVienZone.com https://fb.com/sinhvienzonevn ... „ om How Does Email Work? SinhVienZone. com https://fb .com/ sinhvienzonevn nh Vi en Zo ne C sendmail is the most commonly used mail server in the world, as it generally comes free with Unix and... write a for () loop, and away the emails go!) Si „ Zo http://java.sun .com/ products/javamail/ SinhVienZone. com https://fb .com/ sinhvienzonevn What is JavaMail? -2 om To send JavaMail, you'll need... type the following search string in Google: "MAPI site:msdn.microsoft .com" Si „ C om MAPI SinhVienZone. com https://fb .com/ sinhvienzonevn Si „ nh Vi en Zo „ C „ Apache has a free mail server called