• Branko Mihaljević
• Aleksander Radovan
• Martin Žagar

HUJAK community keynote

HUJAK community keynote

• Keynote
• Introductory

Slides

www.slideshare.net

• Jan Lahoda

The Future of Java is Today (Tech Keynote)

The Java platform experiences an outburst of cool new features – recently, local variable type inference, switch enhancements and multi-line string literals have been added to the Java language. Many other features are being in the pipeline and are actively worked on, like simple data carriers and pattern matching for the Java language, or value classes for the Java virtual machine. These features are delivered quickly, thanks to the recently adopted, predictable, six-months schedule for Java SE releases, which allows for new enhancements to be delivered twice every year! In this talk, we will show a live demo of many of the recently added and newly developed features and improvements for the Java platform, including those mentioned above.

• Keynote
• Introductory

• Boris Spasojevic

GraalVM by example

GraalVM is many things in one.
It is a high-performance, polyglot, embeddable virtual machine and a tool and language development platform.
But what does that mean in practice?
And how do I use GraalVM for my next project?

This session aims to answer such question through a demo-driven overview of the main features and capabilities of GraalVM.
Want to run Java faster?
Compile your Scala command line tool to run without a JVM?
Use you favourite Ruby gem in your node.js webapp?
Write your own high-performance programming language and get a debugger/profiler/coverage tool for free?
Write a tool to understand how your Python script executes?
Use the exact same tool for your R script?
Extend your JVM or native application with scripting capabilities?
Use javascript as part of you SQL query?
GraalVM has you covered.
And this session shows you how to get started.

• Keynote
• Introductory

• Anamarija Talijanac

Quarkus - Supersonic Subatomic Java (Tech Keynote)

Dive into the next generation cloud native framework for running Java in microservice oriented cloud platforms. Quarkus focuses on developers and ease of use in modern serverless environments.
It is a Kubernetes Native Java framework tailored for GraalVM and HotSpot, crafted from best-of-breed Java libraries and standards. 
A hands on overview of the Quarkus cloud native framework, what it brings to the Java ecosystem and the revolutionary concepts and design guidelines it introduces.

• Keynote
• Intermediate

• Marko Talijanac

Low budget low latency transaction systems

Low latency transaction systems were all the rage in 2012. But how to do it in 2020 on a low budget? Tips and tricks on how to achieve low latency target without going overboard.

• Core Java, Frameworks, and Servers
• Intermediate

• Maciej Walkowiak

Concise Spring Boot applications with Kotlin

Java is a simple but very verbose language. Often it feels like it's too verbose and we miss many features that other languages can offer. Can we continue using our favourite frameworks, benefit from JVM reliability and robustness but use more modern and concise programming language? Yes, thanks to Kotlin!

If you haven't used Kotlin ever before there is nothing to worry about. In this talk I will compare side by side Kotlin with Java in examples showing how it can simplify and reduce amount of code in Spring Boot based application.

• Core Java, Frameworks, and Servers
• Introductory

• Dusko Vukmanovic

Serverless With Oracle Functions, Events and API Gateway

Attend this session to learn how you can build modern serverless, event-driven, API-based applications on Oracle Cloud. In this session an overview will be provided of Oracle Cloud's latest serverless building blocks - Oracle Functions, OCI Events and OCI API Gateway. Oracle Functions, our managed Functions-as-a-service platform, when combined with OCI Events and API Gateway provides the ability to run code in response to Oracle Cloud Infrastructure Events and expose the code as REST API endpoints.

• Core Java, Frameworks, and Servers
• Intermediate

• Josip Pojatina

Performance Tuning by using Java Stored procedures

In large enterprises with huge amount of data and thousands of concurrent users, it is crucial to get out the most from each component you are using as part of your enterprise architecture.

Java stored procedures are one of the most overlooked components, mainly due its position on the intersection among several skill sets: Java developer, PL/SQL developers, DBAs and sysadmins.

Within 30 minute session the following topics will be described:
- when you should use (and when not) Java stored procedures
- how to efficiently debug Java stored procedures
- what performance benefits you can expect by involving Java stored procedures

Although session is based on Oracle database, the same approach is valid for any other database system on the market.

• Core Java, Frameworks, and Servers
• Intermediate

• Jamie Coleman
• Yasmin Aumeeruddy

Hands-on cloud-native Java with MicroProfile, Kubernetes and Istio

Ever wondered what makes a cloud-native application “cloud-native”? Ever wondered what the unique challenges are and how best to address them on fully-open Java technologies? In this workshop, you’ll learn what it means to be cloud-native and how that impacts application development. You’ll learn about Eclipse MicroProfile, an industry collaboration defining technologies for the development and management of cloud-native microservices. With a full set of MicroProfile workshop modules available to you, you’ll be able to start with the basics of REST services and progress to more advanced topics, or you can jump right in and develop secure, fault tolerant, configurable and monitorable microservices.

Once you’ve developed your microservice, you’ll learn how to package it in a Docker container and deploy it to a Kubernetes cluster. Finally, you’ll learn the role of a service mesh and use Istio to manage your microservice interactions.

• Core Java, Frameworks, and Servers
• Introductory

• Maciej Walkowiak

The State of Java Relational Persistence

Relational SQL databases are the default and often the best choice for persisting your data. While Hibernate and JPA have dominated the frameworks market there are alternatives worth considering when starting new project.

In this session we will discuss pros and cons of using Java-centric JPA and SQL-centric JOOQ, discover what “the new kid on the block” - Spring Data JDBC has to offer and take a look at the newest addition to Spring Data family - Spring Data R2DBC.

At the end you will have decent high level understanding of all the mentioned frameworks and hopefully make better decision while choosing persistence framework for your next project.

• Core Java, Frameworks, and Servers
• Intermediate

Slides

speakerdeck.com

• Goran Kolevski

You Know, For Search: Deep Dive into ElasticSearch

ElasticSearch is one of the most popular datastores nowadays. Starting just as a distributed version of Lucene it has became a favourite full-text search, data analytics, anomaly detection tool, log aggregation framework etc. But how all this magic happens? In this talk we will dive deep into ElasticSearch and see some of its internals.

• Core Java, Frameworks, and Servers
• Advanced

• Frank Lyaruu

Too young to quit, too old to change: Saving your Legacy Applications using Change Data Capture

We all have aging applications which contain interesting data to use in other applications. In this talk I will look at Change Data Capture to show how we can expose application data without needing to touch the original application, and what we can do with that change stream once we’ve got it.

• Methodologies and Tools
• Intermediate

• Željko Trogrlić

Četiri stupa Kubernetes aplikacije

U današnje se vrijeme Java aplikacija više ne može na miru raširiti po cijelom računalu, nego mora živjeti u skučenom kontejneru. Kako onda priča s vanjskim svijetom? Gdje se spaja struja, voda i kanalizacija? Saznajte koja su vaša četiri glavna kontakta s okolinom i kako ih koristiti.

• Methodologies and Tools
• Introductory

Slides

drive.google.com

• Daniel Strmečki

Learning to Scale Yourself: The Journey from Coder to Leader

Your success depends on others, a 1-man army can only achieve so much. The only way to progress from coder to leader is to learn how to scale yourself. Nowadays, you can become a Senior Developer with just a few years of experience. After that, there are many roads and possibilities you can take. Whether you decide for a developer, architect, manager or a mixed career, at one point, you will need to become a leader. In the first chapter of the lecture we will start a discussion on how to get there. Since your time is limited, you need to mentor, coach, motivate and engage others. Start with making a stable foundation, like setting up a proper onboarding process. If you help people around you, they will for sure talk about it, and your manager will hear it. Also, demonstrate ability in everyday work: coding, project management, client-focus, communication and care about others. Always stick to your values and keep high standards. In the second chapter we will discuss the challenges that turn up once you get there. At that point you will deal with people more than technology. You will need to step away from coding for meetings very often. Interruptions will happen every day and it we be very hard to maintain “the flow”. You will need to learn how to delegate and drive topics without implementing them yourself. Visit the lecture to find out some techniques for dealing with interruptions, meetings, prioritization, people and their motivation.

• Methodologies and Tools
• Advanced

Slides

www.slideshare.net

• Karlo Levak
• Ana Baotić

Building an effective team from zero

The reality that any employer faces today is that it is increasingly difficult to find new talent. Once you do find them, you need keep your employees challenged and happy in order for them to stay.

Last year we took a leap of faith and ventured in setting up an office at a remote location where we previously did not have a significant presence and achieved a mutually beneficial collaboration with the University of Rijeka.
We will demonstrate how we provided industry based knowledge to students, details of our internship program and how we managed to setup and grow an effective team of 9 that is thriving.

Finally, we will share our wins and fails, what we have learned and how we managed to have fun along the way.

• Methodologies and Tools
• Intermediate

• Zeljko Zorko
• Saša Ivičević

Working in distributed agile teams

Agile development usually works well in teams located in one location, but working with distributed, geographically remote teams brings different challenges. How to structure distributed teams to function as one cohesive unit? How to build trust within physically distant groups of people? The main topic of this session is how to develop a unique culture within a team and overcome geographical and cultural differences to meet project goals.

• Methodologies and Tools
• Introductory

Slides

www.slideshare.net

• Ana Baotić
• Martin Grmek

Managing development or developing management - survival instructions

Can't keep them together and you can't keep them apart - project stand still without both. Ones cannot give correct estimations, other understand nothing but deadlines. How do we find common ground and ensure the best conditions for any project to thrive?Join us in discovering the 10 steps for a peaceful and prosperous coexistence of management and development.

• Methodologies and Tools
• Intermediate

• Ivan Lozic

Behaviour Driven Development with Cucumber

Behaviour-Driven Development (or TDD for that matter) is one of the pillars of Software Quality. While it is very important, not many of us do it or do not have the support from the management to invest time in it. Commonly, it has been described as a waste of time or an intangible effort conflicting with the deadlines. In this presentation, I would like to share my experiences with the Behaviour-Driven Development, the effects of not having it at all, as well as the outcomes of working on projects where a significant amount of behavior is automated with Cucumber tool.

By attending this session you will be able to learn what BDD and Cucumber are, how to build Cucumber tests and hear about first-hand experiences around automating specifications.

• Methodologies and Tools
• Intermediate

Slides

www.slideshare.net

• Matej Vidaković

Developing better SDKs with Kotlin

One of the biggest challenges of SDK development is ensuring the ease of use while also preserving full flexibility and all capabilities that the advanced developers need.

In this talk, I'll show you how to overcome these challenges by leveraging Kotlin features that allow us to build internal DSLs.

• Trends, Future, and Community
• Intermediate

• Branko Mihaljević
• Dino Muharemagić
• Matija Šipek
• Paula Pufek
• Dora Beronic

On Java Performance - A Student's Perspective

In this session, we are going to discuss and demonstrate results of some of our research related to Java performance, including:
- Native Images with GraalVM
- Ahead-of-time (AOT) compilation
- JVM-level threads called Fibers
- Better garbage collection

• Trends, Future, and Community
• Introductory

• Darko Jurekovic

Oracle Academy Cloud & Java Courses

You'll learn what's new in the Oracle Academy Program and what is available free of charge to our partners and members in the academic community.

• Trends, Future, and Community
• Intermediate

• Roko Roic
• Marco Hrlić
• Ante Gulin

Scalable IOT architecture for Positioning

We built a positioning and navigation IOT system on low energy bluetooth. Part of the challenge was the mathematics of signal positioning, but a large part was also building a software and cloud architecture for scalability, reliability and performance. We will share our story.

• Innovative and Creative Projects, Experiences and Solutions
• Advanced

• Goran Jelen

Haj'mo razvijati mikroservise! A što sad?

Tijekom transformacije monolita za klijenta naišli smo na mnoga pitanja i izazove koje smo u većini slučajeva uspješno riješili, no ipak ostalo je i onih koji su nam postali još veći izazov. Transformacija je izazivala promjenu određenih razvojnih procesa, dodavanjem nekih novih, te odbacivanjem nekih starih, ali sve s ciljem uspješne transformacije monolita u mikroservise. Kroz predavanje će biti predstavljeno naše iskustvo u transformaciji te kako smo mi odgovorili na pitanje – a što sad?

• Innovative and Creative Projects, Experiences and Solutions
• Intermediate

• Vid Romac

Tell me, what's a server that ain't integrated? - JBoss EAP integracije i XA konfiguracija

Integriranje JBoss EAP servera s tri baze i dva queue managera, koordinacija svih resursa preko XA transakcije.
Bonus - kako to izgleda koristeci WebSphere Liberty Profile.

• Innovative and Creative Projects, Experiences and Solutions
• Intermediate

• Jozo Petrovic

MojA1 transformation

Transformation process of A1 selfcare system from last decade Tibco SOA architecture to more popular Microservice architecture. Now it is written in Java, served on OpenShift cluster offering REST/JSON communication.
As a result, we got reduced processing time while reusing data between microservices and high standard of customer satisfaction, proved by the rating increase from 2.2 to 4.4.

• Innovative and Creative Projects, Experiences and Solutions
• Advanced

Slides

www.slideshare.net

• Matej Vidaković
• Valentina Vidaković

Design for developers

Developer and designer join forces to talk about how important it is to know a bit about design even if you are a developer.
We will teach you some UI / UX design tips and tricks that will help you improve your design skills and we hope to encourage you to learn more about it.

• Other
• Introductory

• Jamie Coleman

The Earths Coolest Data Centers

The world is using technology more than ever before. This means running billions of applications on computers somewhere on the planet but as someone who is concerned for the environment what does that mean? If I pick microservice architecture over monolithic on the cloud, does that save electricity? All cloud hosting companies have their own data centres but if you take cost out of the equation what cloud provider is doing the most to save energy and therefore the planet? This talk will give you a brief look into how these data centres work and the impact they have on the environment.

• Other
• Introductory

• Josip Maslać

Linux terminal for developers

I'm a java developer who likes Linux but is far from something you would call a advanced Linux user.
In this talk I'll demonstrate some of the (basic) practices and tools available in Linux terminal which I regularly use to make my developer/quasi-devops life easier. It is intended for developers not using linux command line in their everyday work but come in touch with it or have to use it from to time to time.

• Other
• Introductory