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<document>
  <properties>
    <title>Examples</title>
    <author email="commons-dev@jakarta.apache.org">Commons Documentation Team</author>
    <author email="quintonm@apache.org">Quinton McCombs</author>
    <revision>$Id: examples.xml,v 1.1 2004/11/25 09:56:56 epugh Exp $</revision>
  </properties>

  <body>
    <section name="A simple text email">
      <p>
        Our first example will create a basic email message to "John Doe" and
        send it through your local mail server.
      </p>
      <source>
<![CDATA[
SimpleEmail email = new SimpleEmail();
email.setHostName("mail.myserver.com");
email.addTo("jdoe@somewhere.org", "John Doe");
email.setFrom("me@apache.org", "Me");
email.setSubject("Test message");
email.setMsg("This is a simple test of commons-email");
email.send();
]]>
      </source>
      <p>
        The call to setHostName("mail.myserver.com") sets the address of the
        outgoing SMTP server that will be used to send the message.  If this is
        not set, the system property "mail.host" will be used.
      </p>
    </section>
    <section name="Sending emails with attachments">
      <p>
        To add attachments to an email, you will need to use the MultiPartEmail
        class.  This class works just like SimpleEmail except that it adds
        several overloaded attach() methods to add attachments to the email.
        You can add an unlimited number of attachments either inline or
        attached.  The attachments will be MIME encoded.
      </p>
      <p>
        The simpliest way to add the attachments is by using the EmailAttachment
        class to reference your attachments.
      </p>
      <p>
        In the following exmaple, we will create an attachment for a picture.
        We will then attach the picture to the email and send it.
      </p>
      <source>
<![CDATA[
// Create the attachment
EmailAttachment attachment = new EmailAttachment();
attachment.setPath("mypictures/john.jpg");
attachment.setDisposition(EmailAttachment.ATTACHMENT);
attachment.setDescription("Picture of John");
attachment.setName("John");

// Create the email message
MultiPartEmail email = new MultiPartEmail();
email.setHostName("mail.myserver.com");
email.addTo("jdoe@somewhere.org", "John Doe");
email.setFrom("me@apache.org", "Me");
email.setSubject("The picture");
email.setMsg("Here is the picture you wanted");

// add the attachment
email.attach(attachment);

// send the email
email.send();
]]>
      </source>
      <p>
        You can also use EmailAttachment to reference any valid URL for files
        that you do not have locally.  When the message is sent, the file will
        be downloaded and attached to the message automatically.
      </p>
      <p>
        The next example shows how we could have sent the apache logo
        to John instead.
      </p>
      <source>
<![CDATA[
// Create the attachment
EmailAttachment attachment = new EmailAttachment();
attachment.setURL(new URL("http://www.apache.org/images/asf_logo_wide.gif"));
attachment.setDisposition(EmailAttachment.ATTACHMENT);
attachment.setDescription("Apache logo");
attachment.setName("Apache logo");

// Create the email message
MultiPartEmail email = new MultiPartEmail();
email.setHostName("mail.myserver.com");
email.addTo("jdoe@somewhere.org", "John Doe");
email.setFrom("me@apache.org", "Me");
email.setSubject("The logo");
email.setMsg("Here is Apache's logo");

// add the attachment
email.attach(attachment);

// send the email
email.send();
]]>
      </source>
    </section>
    <section name="Sending HTML formatted email">
      <p>
        Sending HTML formatted email is accomplished by using the HtmlEmail
        class.  This class works exactly like the MultiPartEmail class with
        additional methods to set the html content, alternative text content
        if the reciepient does not support HTML email, and add inline images.
      </p>
      <p>
        In this exmaple, we will send an email message with formatted HTML
        content with an inline image.
      </p>
      <source>
<![CDATA[
// Create the email message
HtmlEmail email = new HtmlEmail();
email.setHostName("mail.myserver.com");
email.addTo("jdoe@somewhere.org", "John Doe");
email.setFrom("me@apache.org", "Me");
email.setSubject("Test email with inline image");

// embed the image and get the content id
URL url = new URL("http://www.apache.org/images/asf_logo_wide.gif");
String cid = email.embed(url, "Apache logo");

// set the html message
email.setHtmlMsg("<html>The apache logo - <img src=\"cid:"+cid+"\"></html>");

// set the alternative message
email.setTextMsg("Your email client does not support HTML messages");

// send the email
email.send();
]]>
      </source>
      <p>
        First, notice that the call to embed() returns a String.  This String
        is a randomly generated identifier that must be used to reference
        the image in the image tag.
      </p>
      <p>
        Next, there was no call to setMsg() in this example.  The method is
        still available in HtmlEmail but it should not be used if you will be
        using inline images.  Instead, the setHtmlMsg() and setTextMsg()
        methods were used.
      </p>
    </section>
    <section name="Debugging">
      <p>
        The JavaMail API supports a debugging option that will can be very
        useful if you run into problems.  You can activate debugging on any
        of the mail classes by calling setDebug(true).  The debugging output
        will be written to <code>System.out</code>.
      </p>
    </section>
    <section name="Authentication">
      <p>
        If you need to authenticate to your SMTP server, you can call the
        <code>setAuthentication(userName,password)</code> method before sending
        your email.  This will create an instance of
        <code>DefaultAuthenticator</code> which will be used by the JavaMail
        API when the email is sent.  Your server must support RFC2554 in
        order for this to work.
      </p>
      <p>
        You can perform a more complex authentication method such as displaying
        a dialog box to the user by creating a subclass of the
        <code>javax.mail.Authenticator</code> object.  You will need to
        override the <code>getPasswordAuthentication()</code> method where
        you will handle collecting the user's information.  To make use of
        your new <code>Authenticator</code> class, use the
        <code>Email.setAuthenticator</code> method.

      </p>
    </section>
    <section name="Handling Bounced Messages">
      <p>
        Normally, messages which cannot be delivered to a recipient are returned to the
        sender (specified with the <code>from</code> property).  However, in some cases,
        you'll want these to be sent to a different address.  To do this, simply call the
        <code>setBounceAddress(emailAddressString)</code> method before sending
        your email.
      </p>
      <p>
        Technical notes: When SMTP servers cannot deliver mail, they do not pay any attention
        to the contents of the message to determine where the error notification should be
        sent.  Rather, they refer to the SMTP "envelope sender" value.  JavaMail sets this
        value according to the value of the <code>mail.smtp.from</code> property on the 
        JavaMail <code>Session</code>.  (Commons Email initializes the JavaMail 
        <code>Session</code> using <code>System.getProperties()</code>)
        If this property has not been set, then JavaMail
        uses the "from" address.  If your email bean has the <code>bounceAddress</code>
        property set, then Commons Email uses it to set the value of <code>mail.smtp.from</code>
        when the <code>Session</code> is initialized, overriding any other value 
        which might have been set.
      </p>
      <p>
        <em>Note: </em> This is the only way to control the handling of bounced email.  
        Specifically, the "Errors-to:" SMTP header is deprecated and cannot be trusted
        to control how a bounced message will be handled.  Also note that it is considered bad 
        practice to send email with an untrusted "from" address unless you also set the 
        bounce address.  If your application allows users to enter an address which is used
        as the "from" address on an email, you should be sure to set the bounce address
        to a known good address.
      </p>
    </section>
  </body>
</document>