Tuesday, 4 November 2014

Exploration of ideas

There are many professionals for an individual to choose and I believe that e should follow the professional that he like most or hate least. The chance of success and quality of life are both much better that way. So, if you ask me why I choose software development as a career, I can assure you that programming is a fun career. Of course, it is fun not by sitting in front of the monitor and typing endlessly on the keyboard. It is fun because we control what we write and we can let our innovation run wild.

In this article, I want to share some ideas that I have tried and please see for your self if any idea fit your work.


Using OpenExtern and AnyEdit plugins for Eclipse

Of all the plugins that I have tried, these two plugins are my two most favorites. They are small, fast and stable.

OpenExtern give you the shortcut to open file explorer or console for any eclipse resource. At the beginning day of using Eclipse, I often found myself opening project properties just to copy project folder to open console or file explorer. OpenExtern plugin make the tedious 5 to 10 seconds process become 1 second mouse click. This simple tool actually helps a lot because many of us running Maven or Git commands from console.

The other plugin that I find useful is AnyEdit. It adds handful of converting, comparing and sorting tool to Eclipse editor. It eliminates the need to use external editor or comparison tool for Eclipse. I also like to turn on auto formatting and removing trailing spaces when saving. This works pretty well if all of us have the same formatter configuration (line wrapping, indentation,...). Before we standardized our code formatter, we had a hard time comparing and merging source code after each check in.

Other than these two, in the past, I often installed the Decompiler and Json Editor plugins. However, as most of Maven artifacts now a day are uploaded with source code and Json content can be viewed easily using Chrome Json plugin, I do not find these plugins useful anymore.

Using JArchitect to monitor code quality

In the past, we monitored the code quality of projects with eye balls. That seems good enough when you have time to take care of all modules. Things get more complicated when the team is growing or multiple team working on the same project. Eventually, the code still need to be reviewed and we need to be alerted if things go wrong.

Fortunately, I got an offer from JArchitect to try out their latest product. First and foremost, this is a stand alone product rather than traditional way of integrating to IDE. For me, it is a plus point because you may not want to make your IDE too heavy. The second good thing is JArchitect can understand Maven, which is a rare feature in the market. The third good thing is that JArchitect create their own project file in their own workspace, which make no harm to the original Java project. Currently, the product is commercial but you may want to take a look to see if the benefit justify cost


As we all know, a Java web project has both unit test and functional  test. For functional test, if you use framework like Spring MVC, it is possible to create tests for controller without bringing up the server. Otherwise, it is quite normal that developers need to start up server, run functional test, then shutdown the server. This process is a bit tedious given the fact that the project may be created by someone else, which we have never communicated before. Therefore, we are trying to setup project in such a way that people can just download it and run without much hassle.


In the past, we had the server setup manually for each local development box and the integration server (Cruise Control or Hudson). Gradually, our common practice shift toward checking in the server to every project. The motivation behind this move is saving of effort to setup a new project after checking out. Because the server is embedded inside project, there is no need to download or setup the server for each box. Moreover, this practice discourages shared server among projects, which is less error prone.

Other than server, there are two other elements inside a project that are server dependence. They are properties files and database. For each of this element, we have slightly different practice, depending on situation.

Properties file

Checking in properties template rather than properties file

Each developer need to clone the template file and edit when necessary. For continuous integration server, it is a bit trickier. Developer can manually create the file in the workspace or simply check in the build server properties file to the project.

The former practice is not used any more because it is too error prone. Any attempt to clean workspace will delete properties file and we cannot track back the modification of properties in the file. Moreover, as we setup Jenkins as a cluster rather than single node like in the past, it is not applicable any more.

For second practice, rather than checking in my-project.properties, I would rather checkin my-project.properties-template and my-project.properties-jenkins. The first file can be used as guidance to setup local properties file while the second can be renamed and used for Jenkins.

Using host name to define external network connection

This practice may work better sometimes if we need to setup similar network connections for various projects. Let say we need to configure database for around 10 similar project pointing to the same database. In this case, we can hard code the database server in the properties file and manually setup the host file in each build node to point the pre-defined domain of the database.

For non essential properties, provide as much default value as possible

There is nothing much to say about this practice. We only need to remind ourselves to be less lazy so that other people may enjoy handling our projects

Using LandLord Service

This is a pretty new practice that we only apply from last year. With the regulation in our office, Web Service is the only team that manage and have access to UAT and PRODUCTION server. That why we need to guide them and they need to do the repetitive setup for at least 2 environments, both normally require clustering. It is quite tedious to them until the day we consolidate the properties of all environments, all project to a single landlord service.

From that time, each project would start up and connecting to the landlord service with an environment id and application id. The landlord will happily serve them all the information they need.


Using DBUnit to setup database once and let each test case automatically roll back transaction

This is the traditional practice which is still work quite well now a day. However, it still require developer to create an empty schema for DBUnit to connect to. For it to work, the project must have a transaction management framework that support auto roll back in test environment. It also requires that the database operation happen within the test environment. For example, if in the functional test, we attempt to send a HTTP request to the server. In this case, the database operation happen in the server itself rather than in the test environment wen cannot do anything to roll it back.

Running database in memory

This is a built-in feature of Play framework. Developer will work with in-memory database in development mode and external database in production mode. This is doable as long as developer only work with JPA entities and has no knowledge of underlying database system.

Database evolutions

This is a borrowed idea from Ror. Rather than setting up the database from beginning, we can simply check current version and sequentially run the delta script so that the database got the wanted schema. Similar to above, it is expensive to do it yourselves unless there is native support from a framework like Ror or Play.


I have been in the industry for 10 years and I can tell you that software development is like fashion. There is no clear separation between good and bad practice. Whatever things are classified as bad practices may come back another day as new best practices. Let summarize some of the heaty debates we have

Access modifiers for class attributes

Most of us were taught that we should hide class attributes from external access. Instead, we suppose to create getter and setter for each attribute. I strictly followed this rule in my early days even I did not know that most IDE can auto generate getter and setter.

However, later, I was introduced to another idea that setter is dangerous. It allows other developers to spoil your object and mess up the system. In this case, you should create immutable object and do not provide the attribute setter.

The challenge is how should we write our Unit Test if we hide the setter for class attributes. Sometimes, the attributes is inserted to the object using IOC framework like Spring. If there is no framework around, we may need to use reflection util to insert mock dependency to the test object.

I have seen many developers solving problem this way but I think it is over-engineering. If we compromise a bit, it is much more convenient to use package modifier for the attribute. As best practices, test cases will always be on the same package with implementation and we should have no issue injecting mock dependencies. The package is normally controlled and contributed by the same individual or team; therefore the chance of spoiling object is minimal. Finally, as package modifier is the default modifier, it saves a few bytes of your codes.

Monolithic application versus Micro Service architecture

When I joined industry, the word "Enterprise" mean lots of xml, lots of deployment steps, huge application, many layers and the code is very domain oriented. As things evolve, we adopted ORM, learned to split business logic from presentation logic, learn how to simplify and enrich our application with AOP. It goes well until I was told again that the way to move forward is Micro Service Architect, which make Java Enterprise application functions similarly to a Php application. The biggest benefit we have with Java now may be the performance advantage of Java Vitual Machine.

When adopting Micro Service architecture, it is obvious that our application will be database oriented. By removing the layers, it also minimize the benefit of AOP. The code base sure will shrink but it will be harder to write Unit Test.