There are some tools that are considered almost a universal good amongst developers. Revision control systems tend to fall into this category. Everyone ought to be using one. Continuous integration servers are also often bundled in to this category. It’s the kind of tool people ask you during interviews whether you use and judge you… Read more »
Posts By: benji
Cross-functional teams vs Software Architects
This week I have been reading Simon Brown’s leanpub book “Software Architecture for Developers”. It is an interesting read and has lots of useful advice for creating a shared technical vision and communicating technical concepts effectively via sketches. One thing I was struck by while reading it is just how many of the responsibilities of… Read more »
Typesafe database interaction with Java 8
Method references in Java 8 will allow us to build much nicer APIs for interacting with databases. For example when you combine method references with features we already had in Java it’s possible to create clean, typesafe queries without needing code generation. Full examples and implementation available on github. Here’s an example of what’s possible… Read more »
Null Coalescing in Java 8
SQL gives us a “coalesce” function, which returns the first non-null argument. This seems to be a common operation in Java too, since Java unfortunately burdens us with the concept of nulls. We have been able to do something similar with Java for some time using a varargs method like this: public static <T> T… Read more »
StrictMocks in Mockito
Today someone asked how to verify that only your stubbed interactions occur, and no others (when using Mockito). I have heard this asked this quite often, especially by people used to JMock where mocks are strict by default. I’d be interested in knowing if there’s an out of the box way of doing this. The… Read more »
InstanceOf “Smart Casts” with Java 8 Lambdas
As with try-as-expression, there are many other language features we can simulate with Lambdas. Another example is removing the cast commonly needed with instanceof. Kotlin has a nice feature called smart casts, which allows you to do if (x instanceof Duck) { x.quack(); } if (x instanceof Duck) { x.quack(); } Where x is “casted”… Read more »
Try as Expression in Java 8
I’ve been familiarising myself with the new Java 8 language features. It’s great how much easier it is to work around language limitations now that we have lambdas. One annoyance with Java is that try blocks cannot be used as expressions. We can do it with “if” conditionals using the ternary operator. String result =… Read more »
Pair Programming
There was a thread about pair programming on the London Java Community mailing list last week. I tried to contribute to the discussion there, but the mailing list doesn’t receive my replies. So I’ll post my thoughts here instead. I have been pair programming most days in an XP team for the past 3 years…. Read more »
JavaScript shell scripting with Nashorn
One of the nice features of Nashorn is that you can write shell scripts in JavaScript. It supports #!s, #comments, reading arguments, and everything there’s a Java library for (Including executing external processes obviously) Here’s an example #!/home/benji/nashorn7/bin/nashorn #this is a comment print(’I am running from ‘ + __FILE__); var name = arguments.join(’… Read more »
JavaScript tests with JUnit
This weekend I have been playing with Nashorn, the new JavaScript engine coming in Java 8. As an exercise I implemented a JUnit runner for JavaScript unit tests using Nashorn. Others have implemented similar wrappers, we even have one at work. None of the ones I have found do everything I want, and it was… Read more »