DenverJUG

Watch on YouTube: https://www.youtube.com/watch?v=kqNMOJRfGIg

5:30-5:45: Announcements

5:45-7:15: Controlling your race with Micrometer and Spring Boot

Imagine that you’re part of a (car) race team. You’re the one behind the screens to control the race and make some tough decisions (like changing the team’s strategy).

But you don’t have the insights (or metrics) about your car, opponents, or even the weather. Sounds painful right? But why are we making this mistake when building our software? Why don’t we implement metrics by default?

SLFf4J logging is one side of the story, but we also need to know our application health. That’s where Micrometer comes in! It’s a library that you can use to define your own custom metrics, like: – timers (to check the performance of your microservices) – counters (to check how many times a certain event is occurring) – gauges (to check the current value of a variable) – and many more These metrics are exposed by REST endpoints (JSON) together with Spring Boot actuator, which can be saved into a database like Prometheus or Graphite. And to visualize the data you can use a tool like Grafana. Pretty interesting right?

In the demo (live coding!) I will show you how to create such applications using Micrometer, and Spring Boot. Ready to win this race with me? Jump in!

About Ko Turk

Hi, my name is Ko Turk and I am a Senior Java Developer at Blue4IT! I am working as a Fullstack engineer, creating microservices and building frontend applications. As a speaker I am talking at conferences (like JavaZone, DevNexus, and JFall) about IDEs, Micrometer, and Consumer Driven Contract Testing, Please see my speaker credentials at http://ko-turk.nl and please leave me a tweet @KoTurk77.

You can find Ko on Twitter @KoTurk77 (https://twitter.com/KoTurk77).

7:15-7:30: Q & A

The live streaming of this meetup is sponsored by Okta (https://developer.okta.com/).

Wednesday, November 11, 2020 – Online Event

5:30-5:45: Announcements

5:45-7:15: Custom JUnit5 Test Engines

This session explores the possibilities, from @Test over custom extensions up to your own TestEngine. The presentation shows you how to manage a full-stack test in different flavors, based on the JUnit5 possibilities. The main focus is on the development of a custom TestEngine to support project-specific needs. After this, you’ll have all the bits and bytes you need for starting your journey with JUnit5.

About Sven Rupper

Sven is working as Developer Advocate for Jfrog and coding Java since 1996 in industrial projects. He was working over 15 years as a consultant worldwide in industries like Automotive, Space, Insurance, Banking, UN and WorldBank. He is regularly speaking at Conferences and Meetups worldwide and contributes to IT periodicals, as well as tech portals. Additional to his main topic DevSecOps he is working on Mutation Testing of Web apps and Distributed UnitTesting besides his evergreen topics Core Java and Kotlin.

You can find Sven on Twitter @SvenRuppert (https://twitter.com/SvenRuppert).

7:15-7:30: Q & A

The live streaming of this meetup is sponsored by Okta (https://developer.okta.com/).

October 14, 2020

Tune in to watch and chat on YouTube: https://youtu.be/Xw8CnrhPFmI

5:30-5:45: Announcements

5:45-7:15: Comparing Docker Image Build Methods: Cloud Native Buildpacks, Jib, and Docker

Docker images are the deployment artifacts in modern platforms (Kubernetes, Cloud Run, etc). There are a number of ways to create those images from source: `docker build`, the Jib Maven & Gradle plugin, or Cloud Native Buildpacks. This session will provide an overview of the different methods and compare them to help you understand which you should use.

About James Ward

James Ward is a nerd / software developer who shares what he learns with others through presentations, blogs, demos, and code. After over two decades of professional programming, he is now a self-proclaimed Typed Pure Functional Programming zealot but often compromises on his ideals to just get stuff done. After spending too many sleepless nights in data centers repairing RAID arrays, he now prefers higher-level cloud abstractions with appropriate escape hatches. James is a huge Open Source proponent, hoping to never get burned by lock-in again.

You can find James on Twitter @_JamesWard (https://twitter.com/_JamesWard).

7:15-7:30: Q & A

The live streaming of this meetup is sponsored by Okta (https://developer.okta.com/).

5:30-5:45: Announcements

5:45-7:15: Beyond Entitlements for the Cloud Native

A Policy Engine is a tool that allows for checking user privileges as well as evaluate a responsibility matrix based on dynamic data for a given user. A Policy Engine is not only an Entitlement Management System but also provides for functional evaluation of conditions that result in deterministic responsibilities for a given user or actor.

This session shows how to utilize Open Policy Agent with Spring Boot and HOCON to produce a responsibility management solution that scales to volume and performance needs.

Some hiccups that were faced while deriving the most optimal solution are also highlighted. A short explanation of some tooling built for validating the policy files in the IDE will also be discussed.

About Chandra Guntur

Chandra is a technologist in the financial services industry since 2003 and is programming with Java since 1998. Chandra was selected as a 2019 Java Champion. He is a Java User Group (JUG) Leader, and helps run one of the largest Java user groups, NYJavaSIG and leads the NYJavaSIG Hands-On-Workshops (HOW), conducting code workshops and creating Code Katas on core Java features. He is a frequent speaker at Java user groups, and technology conferences including Oracle CodeOne, Oracle Code NY, QCon New York, Devnexus, and GIDS India. Chandra holds a Bachelor’s degree in Technology, Electrical and Electronics Engineering from Sri Venkateswara University.

You can find Chandra on Twitter @CGuntur (https://twitter.com/CGuntur).

7:15-7:30: Q & A

Live streaming of this meetup is sponsored by Okta (https://developer.okta.com/).

Online at https://youtu.be/EYgiO85yFJQ.

5:30-5:45: Announcements

5:45-7:15: Akka Cluster and Akka Typed Deep Dive

You may have heard about the actor model. You may have played with the actor model, but for whatever reason, the opportunity was not there to move forward with it. Well, here is your chance to take a look at the actor model with a set of four Java projects that run Akka clusters. In this talk, we will install, run, and examine in detail a set of example projects. We will explore the code and translate it into what is happening in running clusters.

The projects progressively grow from a basic simple cluster with a few simple actors to actors that message each other across the network, to cluster singleton actors, and finally to cluster sharding. We will also take a look at one of the newest Akka features, Akka Typed.

As a bonus, each project includes a bit of UI eye candy in the form of a web dashboard that will help you gain some institution about the mechanics of Akka and what is happening inside running clusters.

A key takeaway of this talk is that you can download, build, run, and play with each of the projects covered in the talk on your own. Each project also includes a web dashboard that visualizes cluster changes as they happen.

About Hugh McKee

Hugh McKee is a developer advocate at Lightbend. He has had a long career building applications that evolved slowly, that inefficiently utilized their infrastructure, and were brittle and prone to failure. That all changed when he started building reactive, asynchronous, actor-based systems. This radically new way of building applications rocked his world. As an added benefit, building application systems became way more fun than it had ever been. Now he is focused on helping others to discover the significant advantages and joys of building responsive, resilient, elastic, message-driven applications.

You can find Hugh on Twitter @mckeeh3 (http://twitter.com/mckeeh3).

7:15-7:30 Q & A

Wednesday June 10th, 2020, tune in to watch and chat on YouTube: https://youtu.be/AneipVayFss

5:30-5:45: Announcements

5:45-7:15: Thinking Architecturally

Rich Hickey once said programmers know the benefits of everything and the trade-offs of nothing…an approach that can lead a project down a path of frustrated developers and unhappy customers. As architects though, we must consider the trade-offs of every new library, language, pattern, or approach and quickly make decisions often with incomplete information.

How should we think about the inevitable technology choices we have to make on a project? How do we balance competing agendas? How do we keep our team happy and excited without chasing every new thing that someone finds on the inner webs? As architects, it is our responsibility to effectively guide our teams on the technology journey.

In this talk, I will outline the importance of trade-offs, how we can analyze new technologies, and how we can effectively capture the inevitable architectural decisions we will make. I will also explore the value of fitness functions as a way of ensuring the decisions we make are actually reflected in the codebase.

About Nathaniel Schutta

Nathaniel T. Schutta is a software architect focused on cloud computing and building usable applications. A proponent of polyglot programming, Nate has written multiple books, appeared in various videos, and speaks regularly at conferences worldwide, No Fluff Just Stuff symposia, meetups, universities, and user groups. In addition to his day job, Nate is an adjunct professor at the University of Minnesota where he teaches students to embrace dynamic languages. In an effort to rid the world of bad presentations, Nate coauthored the book Presentation Patterns with Neal Ford and Matthew McCullough.

You can find Nathaniel on Twitter @ntschutta (http://twitter.com/ntschutta).

Tune in to watch and chat on YouTube: https://youtu.be/NHEz_G64akI

5:30-5:45: Announcements

5:45-7:15: Essential Spring Data

Data persistence is an essential component of almost every application. But where should the data go? A relational database? A document database? A graph database? Every kind of database has its own unique API, requiring you to pivot your skills depending on what kind of data you’re working with.

Spring Data makes it easy to work with various databases by offering a programming model that is consistent, regardless of which type of database you’re working with. And regardless of the database you’re dealing with, you will find that Spring Data eliminates a lot of boilerplate code.

In this session, you’ll learn how to use Spring Data to rapidly develop repositories for a variety of database types, including relational (JPA and JDBC), document (Mongo), and others (Cassandra, Neo4j, Redis, etc). Time-permitting, we’ll also explore a few advanced techniques for working with Spring Data, such as data projections, reactive repositories, and exposing data APIs automatically with Spring Data REST.

About Craig Walls

Craig Walls is an engineer with VMware and is the author of Spring in Action, Spring Boot in Action, and Build Talking Apps. He’s a zealous promoter of the Spring Framework, speaking frequently at local user groups and conferences and writing about Spring. When he’s not slinging code, Craig is planning his next trip to Disney World or Disneyland and spending as much time as he can with his wife, two daughters, 1 bird and 3 dogs.

You can find Craig on Twitter @habuma (https://twitter.com/habuma).

7:15: Q & A