This week I found a great blog titled, “Mastering Design Patterns in Java”, that delves deep into design patterns specifically in Java. This piece of work aligns with our course topics and focuses on a programming language that many of us are most comfortable with. The writer, Dharshi Balasubramaniyam, discusses six notable design patterns in software engineering:
- Singleton
- Factory
- Builder
- Adaptor
- Decorator
- Observer
The focus of the discussion is how to implement these patterns using detailed examples and how they can be used to deal with common coding scenarios like creating objects, managing inter-class relationships, and optimizing object behavior.
Our work in our course has focused on some of the design patterns that are discussed in this blog, but the rich examples provided here are incredibly valuable when trying to gain a complete understanding of the patterns and learning when to use them. A great example of this is the mention of the Singleton pattern – I am already familiar with this one, but the example being used made the concept easy to remember and understand. The example references the simple idea of the clipboard. If we had more than one instance of the clipboard being accessed by the user of a device, it would be very likely to have conflicting data saved – to avoid this issue we can apply the Singleton pattern to ensure that there is only ever going to be one clipboard instance at any given time. The writer provides the code which enables this example and shows the value of using this design pattern.
One new pattern I learned about was the Builder pattern which focuses on simplifying object construction with required and optional properties. The pattern works to manage the parameters by using a constructor with the required properties and different setter methods with optional properties by using an object class and an objectBuilder class. This pattern provides flexibility for the object being created – the given example creates a user with required properties of name and email and optional properties of phone and city. In the case of the example, we can note that the properties will have their own functions for setter methods which return an objectBuilder object – if the function does not get called to set a new value all optional parameters will contain the string “unknown”. This technique makes the code easy to understand and ensures we are not getting errors due to missing parameters as they will always contain some string.
Using this blog to practice and learn from new examples is extremely helpful and will contribute to the enhancement of my skills as I continue to learn and get more comfortable with writing good, clean code the first time. By implementing the examples shown in the article, I can start noticing opportunities to apply these design patterns in my own work avoiding hours of refactoring code later.
From the blog CS@Worcester by cameronbaron and used with permission of the author. All other rights reserved by the author.