Before you begin reading  you must watch the short 45 second clip.

This video towards the end shows a hesitant thief mustering the courage to pick a pocket. On hearing the kid snap his finger he is disturbed and out of fear drops his idea and walks away, hence a crime has been prevented from happening. It was a coincidence that the thief thought that someone else was looking at him.

I loosely compare this to the Continuous Integration server where the build turns RED for the standards we set. Most of the bad parts while coding goes in inadvertently during the rush hour of check-ins. I usually observe the rush hour to be close to the end of the day and the next day, the refactoring is put into back burner which grows into tech debts and makes you repay at a later stage. Along with the other devs in the team we set some simple rules in the CI to fail the build. The rules are

  • More than 12 lines in a method
  • NPath complexity more than 4 in a method
  • More than 4 lines of code copy pasted across any file

An intentional check in to avoid these rules and send in a bad code could not be prevented; but someone in a hurry or tired individual checking in gets a hint that code could be bad. A quick introspection will lead to corrective action and things could be addressed then and there instead of carrying a tech debt. The rules above are neither comprehensive nor does this guarantee awesome code, but it has caught me and others red handed when looking for quick gains. We are exploring more options to configure the CI to help us keep on our toes.

Hamcrest matchers provided a good way of expressing the assertion in the tests. Combined with the method name and the way you write your assertion it becomes expressive. Bringing it into the middle of development phase when all the other tests have been written using regular assertions was not so desired. So restricted that to starting something from scratch.

Java programmers would have gone through the boring ‘for loop’ and collections manipulations for any applications. Both in the tests and production code it was almost necessary to transform view objects (a necessary evil) to and from models or go through a list and collect the just the names etc. CollectionUtils from apache provided a good way to work through the mundane for loops and do most of that stuff. CollectionUtils.collect(list, new Transformer() {<transformer code>}),  CollectionUtils.select(list, new Predicate() {<predicate code>}) did good help to reduce remove the for loops out of sight.

I then moved on to Groovy which is when I got smitten by the ease at which we can use collections. All we need to do was to call .each or .collect on the collection and put the respective code in the closure. Having tasted this going through the CollectionUtils in java was suddenly looking like an eye sore on the code. I discussed with another developer (incidentally his name is the same as mine) about the problem. He immediately jumped in and said that he had used LambdaJ and it uses Hamcrest matchers. We immediately explored through the code and started replacing Collections.sort to LambdaJ alternative. The code

Collections.sort(personList,new Comparator() {

//comparator code

})

changed to Lambda.sort(personList, on(Person.class).getAge())

Once we tasted success with the first replacement, we went scouting through the code for “for loops & CollectionUtils” and ended up having interesting looking self explanatory code like

Lambda.filter(having(on(Student.class).getAge()) ,is(greaterThan(20)),studentsList)

On doing the static import, the Lambda prefix also disappears. The power of Hamcrest matchers and LambdaJ’s thoughtfully made collection utilities help in making Java code more easy to read. It also has brought closure support to Java (Limited somewhat due to Java’s nature) which looks promising but I am yet to explore its full potential.

As more and more people are getting their hands on other programming languages and switching back to Java due to client requirements are making Java more and more readable and easy to use with these kind of APIs. You can spend more time thinking about the functionality, design rather than getting bored with boilerplate stuff. What else is in store from polyglot programmers?


When I first had a look at the wrapper Boolean data type in Java a funny thought came to my mind about the tri-state nature of a boolean (Why null becomes a possible value?). Later applied the thought to any other data type which is nullable and got funny analogies. Since Object Oriented Programming was related directly to real world, I came up with the following analogy.

Every morning you get your newspaper delivered at your doorstep. The paper boy rings the bell and leaves the paper at your doorstep. Let us assume that the door bell is the function call and newspaper is the object you receive. What happens if you wont get the newspaper delivered?; quite obvious, the paper boy either won’t arrive or will come to your doorstep and communicate why the paper is not delivered.

What would happen if instead of the above scenario the paper boy arrives at your doorstep and delivers a null newspaper? You must receive the newspaper & assert that it is not null and decide to do some other activity, else your day ends abruptly because a null pointer is thrown when you tried to read the newspaper. Now let us not limit this to just newspaper, what about the need to worry about nulls every where? Would not you be driven crazy that you will have to worry about null mails, null phone calls, null water bottles?

This is what happens with many Java programmers where there is some point in their life they had dealt with a sticky, messy null pointer exception caused by some one who had made use of null for a boolean as a logic flow alternative to the true and false state. More worse is the SQL boolean data type having unknown and null as possible values.

So much of code has been written with guard clauses to prevent these nasty null pointer exceptions from getting in and eventually cost 3 extra lines of code in almost all critical business logic methods. Lately I have seen a positive trend among peers in the way we treat nulls. I have seen many consiously avoiding nulls and replacing them with empty objects, Null object pattern or special instances to handle ambiguities. When we move to newer (I would say newly adopted) languages I believe null will cease to exist.