Long time, no see?

Introduction
So what gives? It’s been seven months since my last posting. Have I really been all that busy that I couldn’t find the time to create a new posting?

Well, I guess it’s partly true. I have been busy, but I’m sure I could have found the time if the motivation was there. Rest assured that my guilty conscience has been forever weighing me down for not following up my ‘promising introduction’ to the bloging world. However, I think it’s fair to say that the main reason for my absence can be best described as “self inflicted censorship” – if we can call it that. I’ve been a little uncertain of what to write that would be of interest to others, and also try to avoid pissing off the people I work with. I’ve also been a little rundown at work at times so my eagerness to share my views has not been at it’s peek. Now, a few months the wiser, I guess I’ve gained a little perspective so the picture has become a clearer.

What’s been going on?
A lot has happened during the past seven months. The department I am working for at work has grown substantially from just two people (my boss and I) to around eleven and I guess I’ve been a part of that. My new boss sets targets and does her very best to reach them. Although she is a few years my junior, I’ve learned a lot from her, and for the most part I think she is great to work with. I like her positive attitude and have found it contagious at times. I also take a personal interest in management, good management that is, so I do a little reading on the subject on the side, and have been able to share my views with her on occasion. She is keen to keep everyone in the department happy and find us work that we find interesting. It’s truly great to have a boss that cares and can relate to what I’m doing. With her coming from a Java development background herself helps tremendously and means there has been a lot more focus on Java and Open source technology than earlier. As you may have guessed, that suits me fine, and I feel I have grown a lot, both on a personal and professional level. Compared to where I was a year ago, things are looking good, although the business markets have taken a turn for the worst during the last few months, so who knows what may happen in future? Fingers crossed.

Focus change
Everyone at my present workplace seems to think I live and breath for Java, but I’ve noticed that my main interest actually lies more towards web development based on open source technology than Java development. I haven’t really been following the Java scene actively for quite some time and feel I have fallen behind on the latest API’s and frameworks. At present Java just happens to be the vehicle I use to extract content for web development. My main goal is usually the end result which usually portrays itself in the form of a web application or customer website.

For most of my career I’ve been working behind the scenes on the backend systems, but for a long time I’ve had an interest in web frontend technology. However, it seems that web frontend technology still isn’t taken all that seriously. HTML, CSS and JavaScript are considered technologies that you are expected to pick up as you go along and not really use a lot of time learning. To a certain extent this is true, but I still can’t help but find it odd that this is the case in 2008 considering just how much web development goes on in the world today. Your traditional senior programmer speaks in the language of design patterns and architecture, and although I can appreciate good backend architecture, I sometimes find the frontend a bit more fulfilling and challenging. Maybe because it’s easier to explain to to family and friends what I do for a living? Easier for them to visualize, I guess. 🙂

So, needless to say and according to my current interests, the last few months have been dedicated to working on web applications, creating company web sites and the like. At times it’s been great fun and I’ve learned a lot, especially about CSS which was something I always seemed to down prioritize and found “hard” to get comfortable with. I’m not sure what I really mean when I say “hard”, but for some reason I never really got in to it – mostly down to the fact that I had read a lot about it, but never really practiced it. I could never remember all the property names and their values, which is kind of half the point, I guess. This has now changed and within the last half year I have become more fluent in CSS and have grown to like it, and appreciated it’s power. I’ve also noticed just how bad it can get when more junior developers mess it all up, or don’t think in advance. The resulting CSS becomes a nightmare. I feel there is a great deal to be done on this frontier, but a lot of senior developers don’t want to touch it. Not challenging enough, I presume, which is a shame.

Projects
Just before the summer I got assigned to a project as a backend programmer. We were given the task of creating a company web site for a larger Norwegian gas company. The customer’s technology of choice was IBM’s Web Content Management (WCM). WCM, if you are unfamiliar, is a Java portlet based product that sits on top of WebSphere Portal Server. Although I had worked with both WebSphere Portal Server and WebSphere Application Server in the past, this was a different ball game.
We were two developers assigned to the project and luckily for me the other developer was fluent in CSS and other frontend technologies. He was a couple of years my junior, but I learned a lot from him. We both struggled with WCM at first and had to overcome a relatively high learning curve trying to find a good structure and extract our content before styling, but the end result was very good. The site looks beautiful today and the customer is happy. This was a relatively new experience for me in many ways. I don’t mean to offend anyone, but this was one of the first projects I was a part of where I actually felt I learned something of interest from someone else. Looking back, it was a great experience to follow a project from beginning to end and be part of the entire process. I’m not saying everything went smooth and we had our problems along the way, but in retrospect we did a good job. It’s just a shame the the technology, WCM in this case, is not much in use in my neck of the woods. However, HTML, CSS and jQuery parts, on the other hand, are. I also learned a bit about a few other web related things, like browser compatibility and became somewhat bemused that the tools for frontend technology development are still relatively poor. Was there really life before Firefox and Firebug?

The second project I was part of was to help refactor and expand a Java web application that is part of a company service desk for employee support. Although the technology in question was once again something odd, SAP EP using Java and SAP HTMLB in this case, I was happy to be able to introduce jQuery as a frontend alternative to help create some good looking stuff on the frontend. I was also happy to refactor some of the code, which was in dire need of some attention. Parts of it still is, I’m afraid. Old style JSP code with scriptlets etc. really do suck.

The third and final project I’ve been working on this autumn (and now nearly completed) is based on the open source Java portal, Liferay. Liferay has been a kind of baby of mine for the last 12 to 15 months. A colleague introduced me to it and ever since it seems I have been associated with the product, or at least that’s what everyone thinks at the company. In this project we created a web site for a customer to help their end users recycle materials and goods. We created a great deal of Java portlets in the process using Java, JSP and JSTL. We had to use a few of the new features of JSR-286 to get things working. In this project I also introduced jQuery into my frontend code which most certainly made some code a lot easier to both read and maintain. My CSS skills came in handy as well.

Conclusion
So there you have it and that’s it for now. A brief summary of what I’ve been up to for the past few months. Hopefully, I’ll have more for you soon, but don’t be surprised if it has more to with web development than backend programming, since that’s where my interests are at present. I’ve been reading a lot lately so expect a few book reviews soon. 🙂

Take care!

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Sending SMTP mail with Java

Introduction

So your Java application needs to send a notification mail? Not an uncommon scenario, but how to do it? Luckily this turns out to be pretty easy in it’s simplest form, but SMTP configuration can be the killer. You are of course dependent on being able to access a SMTP mail server and also possessing a little knowledge of the SMTP protocol.

What you need

Some years ago, Sun released the Java Mail API. It doesn’t ship along with the standard Java distribution (yet!) so you will need to download it manually. It can be found here and at the time of writing is at version 1.4.1. The Mail API depends on code from the JavaBeans Activation Framework (JAF) so you’ll need to download that package also. It can be found at this link and at the time of writing is at version 1.1.1. Make sure you add the activation.jar file from the JAF distribution to your Java classpath and you will also need both the mail.jar and smtp.jar files from the Mail API distribution to enable you to send SMTP mail.

The code

The code itself is straightforward enough, but as I said earlier, it’s the SMTP mail server configuration that can turn out to be the problem. Specially if the server is configured to not let you use it indiscriminately to avoid SPAM etc. This will depend on the company policy configuration settings of the SMTP server you are trying to connect to.

OK, here’s a simple example of how it can be done…

import java.util.Date;
import java.util.Properties;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;

public class Main {
    public static void main(String[] args) {
        Properties props = new Properties();
        props.put("mail.smtp.host", "your SMTP mail server here");
        props.put("mail.debug", "true");

        Session session = Session.getInstance(props);

        try {
            Message msg = new MimeMessage(session);
            msg.setFrom(new InternetAddress("from@here.com"));
            InternetAddress[] address = {new InternetAddress("to@somewhere.com")};
            msg.setRecipients(Message.RecipientType.TO, address);
            msg.setSubject("Mail subject title");
            msg.setSentDate(new Date());
            msg.setText("Message body string");

            Transport.send(msg);
        }
        catch (MessagingException e) {}
    }
}

So, to summarize, start you of by creating a Java Properties object and populating it with relevant configuration information. You need to specify the SMTP host name or IP address for the key “mail.smtp.host”. The “mail.debug” property is useful for development and will give you a hint what’s going wrong should you get into trouble. Proceed on by creating a javax.mail.Session object and passing it your properties object. To create the actual mail message use a javax.mail.internet.MimeMessage object passing along the session instance you just created. Populate the javax.mail.Message object with a valid sender address and receiver address array (mail has only one sender, but can have multiple receivers). Add a mail subject, the timestamp and of course the mail message body. Then all that remains is to actually post the message to the SMTP server. That where the hard part usually begins.
So, not that difficult all in all, but remember to encapsulate the code in a try/catch block and catch the javax.mail.MessagingException exception type for it to compile. Handle errors appropriately, there is a lot that could possibly go wrong here.

SMTP server authentication

As I mentioned earlier, configuration can be the killer. These days most SMTP servers don’t let any old message pass through the system without some kind of policy checking switched on. It is likely that you will need to authenticate your application to the SMTP server when creating the session object. It is also possible that the server will attempt to validate the sender e-mail address your application is using so you need to choose it wisely since it will need to be valid in the mail domain.

To create an authenticated session object you will need to make a few minor adjustments to the code. Create a javax.mail.Authenticator subclass and override the protected method getPasswordAuthentication. By default this method returns null, so you will have to make it return an initialized javax.mail.PasswordAuthentication object containing your username and password.

You also need to tell the session object to use your new authentication class so add the property “mail.smtp.auth” to your Properties object and set its to “true”. Also change the code that creates the session object by using an overloaded version passing both your Properties object and an instance of your new Authenticator subclass. The new code should look something like this:

import java.util.Date;
import java.util.Properties;
import javax.mail.Authenticator;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.PasswordAuthentication;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;

public class Main {
    public static void main(String[] args) {
        Properties props = new Properties();
        props.put("mail.smtp.host", "your SMTP mail server here");
        props.put("mail.smtp.auth", "true");
        props.put("mail.debug", "true");

        Session session = Session.getInstance(props, new MyAuth());

        try {
            Message msg = new MimeMessage(session);
            msg.setFrom(new InternetAddress("from@here.com"));
            InternetAddress[] address = {new InternetAddress("to@somewhere.com")};
            msg.setRecipients(Message.RecipientType.TO, address);
            msg.setSubject("");
            msg.setSentDate(new Date());

            msg.setText("Message body string");

            Transport.send(msg);
        }
        catch (MessagingException e) {}
    }
}

class MyAuth extends Authenticator {
    protected PasswordAuthentication getPasswordAuthentication() {
        return new PasswordAuthentication("your username","your password");
    }
}

And that ought to do it! This code worked fine for me when testing with two separately configured Microsoft Exchange servers (ESMTP , version 6.0.3790.1830 and 6.0.3790.3959) in different mail domains as my SMTP server host, but only if clear text authentication (BASIC) was enabled on the Exchange server.

In both cases the Exchange server checked my sender address and also insisted that my application authenticate itself before allowing it to post.