Retread of post orginally made on 24 Jul 2009
One of the most powerful tools in writing maintainable code is break large methods into well-named smaller methods - a technique Kent Beck refers to as the Composed Method pattern.
I am an author, speaker, and loud-mouth on the design of enterprise software. I work for ThoughtWorks, a software delivery and consulting company. This site contains lots of my writing on software development, which primarily focuses on software design and agile methods. To find your way around this site, go to the intro guide.
My atom feed (RSS) announces any updates to this site, as well as various news about my activities and other things I think you may be interested in. I also make regular announcements via my twitter feed, which I copy to my facebook page.
Thu 31 Jul 2014 08:26 EDT
Mon 28 Jul 2014 09:56 EDT
In this final installment I touch on laziness, parallelism, and immutability then conclude by outlining when we should use collection pipelines.
Sat 26 Jul 2014 16:34 EDT
Thu 24 Jul 2014 08:57 EDT
In this installment I look at alternatives to using a collection pipeline: loops and comprehensions.
Wed 23 Jul 2014 09:20 EDT
I’ve added a more complex example to the article, one that inverts a many-to-many relationship. This also raises the question of how to factor more complex pipelines
Tue 22 Jul 2014 10:04 EDT
I’ve added two more examples of collection pipelines with this second installment. The first is the classic combination of map and reduce, also introducing specifying functions with names as well as lambdas. The second introduces the group-by operation and treating hashmaps as key-value pairs.
Mon 21 Jul 2014 09:12 EDT
I’ve often come across a pattern in code where you organize some computation by passing collections through a pipeline of operations. I first came across it in Unix, did it in Smalltalk and Ruby, and find it common in functional programming. I’ve written an article to describe this pattern, and this is the first installment which contains an initial introduction and a definition of the pattern.
Sun 06 Jul 2014 13:07 EDT
For a long time I’ve been a champion of Continuous Integration which reduces integration risk by integrating early and often, an application of the principle of Frequency Reduces Difficulty. We’ve found CI to be a core technique at ThoughtWorks and use it almost all the time. At the heart of this is a style of development that minimizes long feature branches with techniques like Branch By Abstraction and Feature Toggles.
While this is useful, there was still risk present from software that works in the development environment to getting it to work in production. As a result we developed Deployment Pipelines to reduce this risk, moving closer to our aim of Continuous Delivery: building software in such a way that we confidently deploy the latest builds into production whenever there is a business need. We find this improves feedback, reduces risk, and increases the visibility of project progress.
For more information: take a look at my guide page on Continuous Delivery.
I’ve been involved in enterprise software for two decades and while we’ve seen huge technological change during that time, the relational database has been a constant figure. Previous attempts to dethrone relational databases have failed, but some people think the new rise of NoSQL databases will finally consign relational databases to history. While I think relational databases are going to an important part of the landscape for a long time, I do think that there is a big change coming in the database field.
I discovered ThoughtWorks in 2000: then a small American company whose philosphy of software development was remarkably similar to my own. Now we’ve grown to around 2500 people world-wide, but kept the values that make us special. My colleagues have built critical systems for many clients in that time, and I’ve learned many lessons from them. While doing this, we found we often didn’t have the tools we needed, so we started to build them. This led to open-source tools such as CruiseControl, Selenium, Frank, and Moco as well as commercial products.
I have many opportunities, but I’ve stayed at ThoughtWorks because of the quality of my colleagues, who include both well-known speakers and those who may not be famous names but do an excellent job of software delivery (and feed me the information to write about). We are inspired by working with each other and our unusual three-pillar philosophy that raises professional excellence and social justice to the same level as financial performance.
And we are always looking for more great people to join our curious company. Maybe I’ll see you in one of our offices some day.
As with any style of process, agile software development has bred lots of interest in metrics. The thinking goes something like this, “We need a number to measure how we’re doing. Numbers focus people and help us measure success.” Whilst well intentioned, management by numbers unintuitively leads to problematic behavior and ultimately detracts from broader project and organizational goals. Metrics inherently aren’t a bad thing; just often, inappropriately used. Pat Kua, author of The Retrospective Handbook, demonstrates these issues and offers an alternative approach that uses metrics well.