Preamble I have started cleaning up and updating my Github account https://github.com/dpweberza as more and more companies these days are likely to view it. Because I don’t have many open-source projects, I have uploaded a rather meaty coding challenge that I completed back in 2015. The Coding Challenge In 2015 I interviewed at a global mobile payments company for the position of Android Developer. At the time I had no commericial Android development experience but nevertheless was invited to complete a coding challenge after I had passed a screening call.

Preamble In an effort to contribute more to my blog and help jog my memory, I have decided to start a series of blogs detailing some popular design patterns and how I have used them. Chain of Responsiblilty The Chain of Responsibility pattern is defined as follows: “Gives more than one object an opportunity to handle a request by linking receiving objects together” - Gang of Four book on Design Patterns

The other day I was building our new orders interface in VueJS and I came across a performance problem on large orders where we were creating a large number of Hibernate objects in one request. For 750 objects the request was taking around 2 minutes. This was certainly unacceptable as the whole reason I was building a new orders interface was to scale better and provide a better UX. So I started looking at options to do a batch insert instead, unfortunately we are stuck on Hibernate 2 at the moment due to a rather large code base that cannot be easily upgraded.