Welcome!

Microservices Expo Authors: Kevin Benedict, Yeshim Deniz, Elizabeth White, Jyoti Bansal, Pat Romanski

Related Topics: Java IoT, Industrial IoT, Microservices Expo, Machine Learning

Java IoT: Product Review

Design Patterns in Java LiveLessons Review

LiveLessons Video Training the Downloadable Version

I have spent the past few weeks watching this video series. I started watching it on the treadmill in the morning before work. I did that until I hit lesson 5. It is 4 hours and 20 minutes long. I started watching lesson 5 in front of the computer, not because I didn't want to walk for over four hours, but because I wanted to look at the code you can download with these lessons.

In lesson 5 covers a ton of patterns. The thing I like most about the way the patterns are introduced is that they are introduced working with other patterns. The way patterns should be used, together.

He uses lots of diagrams and walks through the tons of code making sure the patterns are thoroughly cover.

The thing I liked most about the course was that the speaker is not a pattern zealot. He makes sure to tell you when you would not want to use patterns and why. He gives the advantages and disadvantages of each pattern.

The downloadable code is very well organized and usable. It was really nice to just import the project, build it, and run it. No issues at all. I am not usually that lucky with Java samples.

You do not need to know Java to watch this course. I do very very little in Java. I am in Objective-C or C# 90% of the time I am in code. I do have a lot of experience with patterns at all levels (code, integration, architectural, information management, enterprise, etc.). Although you can do without Java, I do recommend you have OOP under your belt. I also felt having the past experience with pattern really helped me keep up.

If you don't have pattern experience, I think you may have to work a little harder to keep up. That is not a bad thing because the material covered is real worth the extra effort to get under your belt. The more you work at understanding the concepts the the speaker cover, the more embedded in your development thought process it will become.

Below is a brief overview of each lesson. They are taken from the publisher's web site.

Lesson 1:
Experts in most domains perform quite differently than beginners. For example, professional athletes, musicians, and dancers move fluidly and effortlessly, without focusing on each individual movement. Likewise, when master software developers write code, they approach it differently than novices, drawing on years of design experience to help guide their solutions.

When watching experts perform, it's often easy to forget how much effort they put into reaching these high levels of achievement. Continuous practice, repetition, and mentoring from other experts are crucial to their success. At the heart of all these activities is knowledge and mastery of patterns, which are reusable solutions to common problems that arise within particular contexts.

In this lesson you learn to recognize the importance of design experience when becoming a master software developer. You also learn what patterns are and how they help codify design experience to improve software quality and developer productivity. In addition, you learn the common characteristics of patterns and pattern descriptions. Finally, you learn about the history of the Gang of Four book and its patterns, as well as learn about key types of relationships among patterns.

Lesson 2:
While it’s certainly possible to discuss patterns in the abstract, good design and programming practices are not best learned through generalities and platitudes. Instead, it’s more effective to see how significant programs can be made easier to write and read, easier to maintain and modify, and more efficient and robust via the application of time-proven software patterns.

This lesson therefore presents an overview of an expression tree processing app that we use as a case study throughout the course. You learn about the goals of this case study, which provides a realistic–yet tractable–context in which to explore the why, the how, and the benefits and limitations of applying many Gang of Four design patterns to an application written in Java. Using the case study as a guide, you also learn how to recognize key structural and behavioral properties in a domain, as well as understand the case study's functional and non-functional requirements.

All the pattern-oriented software presented in the case study is available in open-source form from the course website. You can see throughout the course that applying Gang of Four patterns in the case study not only improves the application’s modularity, extensibility, and quality but also enhances its portability so that it runs on a range of Java platforms, including Android and Eclipse.

Lesson 3:
Algorithmic decomposition is a historically popular software development method that structures software based on the actions performed by algorithms in a program. It decomposes general actions in an algorithm iteratively and recursively into more specific actions. The design components in an algorithmic decomposition typically correspond to processing steps in an execution sequence, which are usually implemented via functions or procedures.

In this lesson you learn how to develop an algorithmic decomposition of the expression tree processing app case study. You also learn how to evaluate the benefits and limitations of algorithmic decomposition. This material provides a baseline for comparison with our pattern- and object-oriented expression tree processing app presented in subsequent lessons.

Lesson 4:
Object-oriented design is a method of planning a system of interacting objects to solve software problems. This design paradigm employs hierarchical data abstraction, where components are structured based on stable class/object roles and relationships, rather than functions corresponding to actions (as is the case with algorithmic decomposition). Moreover, object-oriented design associates actions with classes of objects in a manner that emphasizes high cohesion and low coupling. In many well-designed object-oriented programs, classes and objects are defined and associated in accordance with patterns and combined to form frameworks.

In this lesson you learn how to develop an object-oriented design for the expression tree processing app case study. In addition, you learn how to evaluate the benefits and limitations of object-oriented design relative to the algorithmic decomposition approach presented in Lesson 3.

Lesson 5:
The book Design Patterns: Elements of Reusable Object-Oriented Software (the so-called “Gang of Four” book) presents 23 patterns that document recurring solutions to common problems that arise when developing software in particular contexts. In this lesson you learn how more than a dozen patterns from the Gang of Four book can be applied to the Java-based expression tree processing app case study to resolve key design problems and improve the apps modularity, extensibility, portability, and quality. This lesson forms the bulk of the course and covers the following patterns:

• Composite, which treats individual objects and multiple, recursively-composed objects uniformly.
• Bridge, which separates an abstraction from its implementation(s) so the two can vary independently.
• Interpreter, which when given a language, defines a representation for its grammar.
• Builder, which separates the construction of a complex object from its representation.
• Iterator, which accesses elements of an aggregate without exposing its representation.
• Strategy, which defines a family of algorithms, encapsulates each one, and makes them interchangeable.
• Visitor, which centralizes operations on an object structure so that they can vary independently.
• Command, which encapsulates the request for a service as an object.
• Factory Method, which provides an interface for creating an object, but leaves the choice of the concrete type to a subclass.
• State, which allows an object to alter its behavior when its internal state changes, making object appear to change its class.
• Template Method, which provides a skeleton of an algorithm in a method, deferring some steps to subclasses.
• Singleton, which ensures a class only has one instance and provides a global point of access.

The lesson also touches on several other Gang of Four patterns, including Abstract Factory, Adaptor, Decorator, and Observer.

Lesson 6:
The pattern- and object-oriented version of the expression tree processing app case study presented in Lesson 5 provided many improvements compared with the algorithmic decomposition approach described in Lesson 3. For example, it's much more modular and extensible, its design matches the domain better, and it incurs less space overhead. The design of the expression tree process app also exhibits “high pattern density.” For instance, nearly all its classes play a role in one or more Gang of Four patterns. In addition, patterns help clarify the relationships of the many classes comprising the case study’s design. The same pattern-oriented design can be implemented readily in many popular object-oriented programming languages. For example, the Java and C++ solutions are nearly identical, modulo minor syntactic and semantic differences in these two languages. Although pattern- and object-oriented solutions are powerful, becoming a master software developer requires a balanced and nuanced understanding of the pros and cons of patterns. In this lesson, you learn how to evaluate both the benefits and limitations of patterns.

I highly recommend this video series to anyone working in an object oriented language.

Get the video series here.

If you have no design pattern experience at all, below are a few of the best available on the topic.

More Stories By Tad Anderson

Tad Anderson has been doing Software Architecture for 18 years and Enterprise Architecture for the past few.

@MicroservicesExpo Stories
The evolution of JavaScript and HTML 5 to support a genuine component based framework (Web Components) with the necessary tools to deliver something close to a native experience including genuine realtime networking (UDP using WebRTC). HTML5 is evolving to offer built in templating support, the ability to watch objects (which will speed up Angular) and Web Components (which offer Angular Directives). The native level support will offer a massive performance boost to frameworks having to fake all...
All clouds are not equal. To succeed in a DevOps context, organizations should plan to develop/deploy apps across a choice of on-premise and public clouds simultaneously depending on the business needs. This is where the concept of the Lean Cloud comes in - resting on the idea that you often need to relocate your app modules over their life cycles for both innovation and operational efficiency in the cloud. In his session at @DevOpsSummit at19th Cloud Expo, Valentin (Val) Bercovici, CTO of Soli...
"We're bringing out a new application monitoring system to the DevOps space. It manages large enterprise applications that are distributed throughout a node in many enterprises and we manage them as one collective," explained Kevin Barnes, President of eCube Systems, in this SYS-CON.tv interview at DevOps at 18th Cloud Expo, held June 7-9, 2016, at the Javits Center in New York City, NY.
The rise of containers and microservices has skyrocketed the rate at which new applications are moved into production environments today. While developers have been deploying containers to speed up the development processes for some time, there still remain challenges with running microservices efficiently. Most existing IT monitoring tools don’t actually maintain visibility into the containers that make up microservices. As those container applications move into production, some IT operations t...
Docker containers have brought great opportunities to shorten the deployment process through continuous integration and the delivery of applications and microservices. This applies equally to enterprise data centers as well as the cloud. In his session at 20th Cloud Expo, Jari Kolehmainen, founder and CTO of Kontena, will discuss solutions and benefits of a deeply integrated deployment pipeline using technologies such as container management platforms, Docker containers, and the drone.io Cl tool...
For organizations that have amassed large sums of software complexity, taking a microservices approach is the first step toward DevOps and continuous improvement / development. Integrating system-level analysis with microservices makes it easier to change and add functionality to applications at any time without the increase of risk. Before you start big transformation projects or a cloud migration, make sure these changes won’t take down your entire organization.
SYS-CON Events announced today that CA Technologies has been named “Platinum Sponsor” of SYS-CON's 20th International Cloud Expo®, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY, and the 21st International Cloud Expo®, which will take place October 31-November 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. CA Technologies helps customers succeed in a future where every business – from apparel to energy – is being rewritten by software. From ...
SYS-CON Events announced today that Outlyer, a monitoring service for DevOps and operations teams, has been named “Bronze Sponsor” of SYS-CON's 20th International Cloud Expo®, which will take place on June 6-8, 2017, at the Javits Center in New York City, NY. Outlyer is a monitoring service for DevOps and Operations teams running Cloud, SaaS, Microservices and IoT deployments. Designed for today's dynamic environments that need beyond cloud-scale monitoring, we make monitoring effortless so you...
DevOps is being widely accepted (if not fully adopted) as essential in enterprise IT. But as Enterprise DevOps gains maturity, expands scope, and increases velocity, the need for data-driven decisions across teams becomes more acute. DevOps teams in any modern business must wrangle the ‘digital exhaust’ from the delivery toolchain, "pervasive" and "cognitive" computing, APIs and services, mobile devices and applications, the Internet of Things, and now even blockchain. In this power panel at @...
Cloud Expo, Inc. has announced today that Andi Mann and Aruna Ravichandran have been named Co-Chairs of @DevOpsSummit at Cloud Expo 2017. The @DevOpsSummit at Cloud Expo New York will take place on June 6-8, 2017, at the Javits Center in New York City, New York, and @DevOpsSummit at Cloud Expo Silicon Valley will take place Oct. 31-Nov. 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA.
With 10 simultaneous tracks, keynotes, general sessions and targeted breakout classes, Cloud Expo and @ThingsExpo are two of the most important technology events of the year. Since its launch over eight years ago, Cloud Expo and @ThingsExpo have presented a rock star faculty as well as showcased hundreds of sponsors and exhibitors! In this blog post, I provide 7 tips on how, as part of our world-class faculty, you can deliver one of the most popular sessions at our events. But before reading the...
TechTarget storage websites are the best online information resource for news, tips and expert advice for the storage, backup and disaster recovery markets. By creating abundant, high-quality editorial content across more than 140 highly targeted technology-specific websites, TechTarget attracts and nurtures communities of technology buyers researching their companies' information technology needs. By understanding these buyers' content consumption behaviors, TechTarget creates the purchase inte...
@DevOpsSummit at Cloud taking place June 6-8, 2017, at Javits Center, New York City, is co-located with the 20th International Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world. The widespread success of cloud computing is driving the DevOps revolution in enterprise IT. Now as never before, development teams must communicate and collaborate in a dynamic, 24/7/365 environment. There is no time to wait for long developm...
Microservices (μServices) are a fascinating evolution of the Distributed Object Computing (DOC) paradigm. Initial design of DOC attempted to solve the problem of simplifying developing complex distributed applications by applying object-oriented design principles to disparate components operating across networked infrastructure. In this model, DOC “hid” the complexity of making this work from the developer regardless of the deployment architecture through the use of complex frameworks, such as C...
DevOps and microservices are permeating software engineering teams broadly, whether these teams are in pure software shops but happen to run a business, such Uber and Airbnb, or in companies that rely heavily on software to run more traditional business, such as financial firms or high-end manufacturers. Microservices and DevOps have created software development and therefore business speed and agility benefits, but they have also created problems; specifically, they have created software securi...
Microservices are a very exciting architectural approach that many organizations are looking to as a way to accelerate innovation. Microservices promise to allow teams to move away from monolithic "ball of mud" systems, but the reality is that, in the vast majority of organizations, different projects and technologies will continue to be developed at different speeds. How to handle the dependencies between these disparate systems with different iteration cycles? Consider the "canoncial problem" ...
Both SaaS vendors and SaaS buyers are going “all-in” to hyperscale IaaS platforms such as AWS, which is disrupting the SaaS value proposition. Why should the enterprise SaaS consumer pay for the SaaS service if their data is resident in adjacent AWS S3 buckets? If both SaaS sellers and buyers are using the same cloud tools, automation and pay-per-transaction model offered by IaaS platforms, then why not host the “shrink-wrapped” software in the customers’ cloud? Further, serverless computing, cl...
Hardware virtualization and cloud computing allowed us to increase resource utilization and increase our flexibility to respond to business demand. Docker Containers are the next quantum leap - Are they?! Databases always represented an additional set of challenges unique to running workloads requiring a maximum of I/O, network, CPU resources combined with data locality.
As software becomes more and more complex, we, as software developers, have been splitting up our code into smaller and smaller components. This is also true for the environment in which we run our code: going from bare metal, to VMs to the modern-day Cloud Native world of containers, schedulers and micro services. While we have figured out how to run containerized applications in the cloud using schedulers, we've yet to come up with a good solution to bridge the gap between getting your contain...
An overall theme of Cloud computing and the specific practices within it is fundamentally one of automation. The core value of technology is to continually automate low level procedures to free up people to work on more value add activities, ultimately leading to the utopian goal of full Autonomic Computing. For example a great way to define your plan for DevOps tool chain adoption is through this lens. In this TechTarget article they outline a simple maturity model for planning this.