There’s no doubt that Blockchain is a rapidly growing and evolving technology. If you work on Enterprise systems then there’s reasonable chance there’s a use case where Blockchain could help. This session will help you understand Blockchain and how your Java skills apply. The session will provide an introduction to Blockchain along with use cases. With the aid of relevant demos and the Linux Foundation’s Hyperledger Fabric & Composer projects, you will learn how to get started with Blockchain technologies, develop and deploy Blockchain applications, and integrate with them from your favorite Java environment.

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Because of the explosive growth of the internet, performance requirements for web applications
have grown accordingly. A few years ago the C10K problem was a huge challenge… servers handling
10000 connections at the same time. Nowadays, Twitter gets 300000 requests per second.
Vert.x is a lightweight, asynchronous, event-driven, scalable application framework for reactive
applications on the JVM. It is Open Source and is currently one of the most popular JAVA projects on
Github.
We will together investigate, on the basis of a real architecture, its potential and give you a head
start on this technology.

There is only one path to sustainability : avoid the so-called commodity magnet. New products are -after some time- pulled to this virtual magnet which increases cost, and reduces income for these products. To avoid this, every company has to continuously invest in Innovation to bring new products to the market place.
So, how can one innovate ? What are the secrets to stay ahead of competition ? Why are many companies not able to grow using innovation ? What is the secret to come to the Eureka moment that will push the organization and its employees up the ladder?

Discuss the future of Jakarta EE with the main people behind it!

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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, plus utilising OpenJ9 for memory reduction.

Planning to build microservices? The best practice of building a first-class microservice is to follow 12-Factor app. But how to fulfill the 12-factor app rules, e.g. how to achieve externalise the configuration, fault tolerance, etc? Come to this session to build a 12-factor microservice using MicroProfile programming mode with live code demo.

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Java has finally shipped with modules! You’ve attended presentations and read articles about Java 9 modules, but how do you actually go about modularizing an application? This session will present a practical example in which an application is modularized. Application architecture, dependencies, and tooling will be covered. Hopefully this will give you a better idea of what is involved in modularizing an application and the benefits it provides.

Contexts and Dependency was introduced in Java EE 6 and has since become a core technology. This lab will cover the basic features of CDI 1 and 2. Everything from injection and scopes to decorators, transactions, concurrency, and testing will be covered.

Memory leaks are not always simple or easy to find. Heap dumps from production systems are often gigantic (4+ gigs) with millions of objects in memory. Simple spot checking with traditional tools is woefully inadequate in these situations, especially with real data. Leaks can be entire object graphs with enormous amounts of noise. This session will show you how to build custom tools using the Apache NetBeans Profiler/Heapwalker APIs. Using these APIs, you can read and analyze Java heaps programmatically to ask really hard questions. This gives you the power to analyze complex object graphs with tens of thousands of objects in seconds.

Discuss the future of Jakarta EE with the main people behind it!

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JNoSQL is a framework and collection of tools that make integration between Java applications and NoSQL quick and easy — for developers as well as vendors. The API is easy to implement, so NoSQL vendors can quickly implement, test, and become compliant by themselves. And with its low learning curve and just a minimal set of artifacts, Java developers can start coding by worrying not about the complexity of specific NoSQL databases but only their core aspects (such as graph or document properties). Built with functional programming in mind, it leverages all the features of Java 8. This session covers how the API is structured, how it relates to the multiple NoSQL database types, and how you can get started and involved in this open source technology.

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With traditional software unit tests, there’s never a guarantee that an application will actually function correctly in the production environment. And when you add microservices, remote resources that are accessible over a network, into the mix, testing is more tricky. To make things even harder, microservices typically need to collaborate with additional network-based microservices, making testing even more challenging. Moving to microservices implies a change in the mindset of developers, so will using old testing techniques with new architectures still work?

In this session, you’ll learn test strategies that solve the most common issues likely to be encountered when writing tests for a microservices architecture. We will look at how tools such as Arquillian, JUnit, Docker and techniques such as service virtualization, consumer-driven testing and testing in production with Istio can aid in accomplishing this task.

Create you very first Helidon-SE and Helidon-MP microservice!

Come learn about developing microservices using Helidon. Helidon is an open source project led by Oracle. Helidon contains a collection of Java libraries for building microservices. In this session we will talk about two programming models supported by Helidon: lightweight, functional model using JDK as runtime for those wanting less “magic” and Microprofile for those wanting inversion of control and familiar Java EE APIs. We will show how to quickly create your first Helidon application which uses both programming models.

Data is the new gold. Security problems and data leaks are getting more and more attention in the media. Privacy and integrity of your clients (personal) data is more than a hot topic. Are you as a developer prepared?! On the other hand, you could be part of the problem as well. So, how secure are you and how secure is your work.

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In Java 8 functional style programming was introduced in Java. Java 9 extended this with some nice new features. For many people it is hard to grasp the idea of functional style programming after so many years of purely working in the imperative OOP style. The opportunities Java gives us out of the box are massive, but with great power comes great responsibility.

Brian points out common mistakes that are made when integrating functional style programming in your every day Java project and how to prevent this. This way you can write better, cleaner and more readable code. But even more important, you will be able to utilize the functional code constructions in Java 9 to it’s full potential… and maybe, you even start to like it.

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Sometimes you have to join the Dark Side – temporally. Writing documentation and preparing presentations as software developer is bad enough but using Microsoft Office makes it unbearable. Be real – BLOBs shared over email, file system and/or Slack is a thing of the past. We want our stuff text-based and version controlled but sometimes Markdown does not cut it. But help is near – learn how to get an efficient work-flow using Sublime & Maven to generate beautiful PDFs and reveal.js presentations.

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You think of using Gatling to run performance test? But got confused with Scala, DSL and documentation? This presentation shows how to write Gatling tests in your IDE, execute them on the command line and push them into your CI server of choice. Afterwards we discuss a few of Gatling’s feature such as injection profiles, scenario implementation, test configuration and last but not least debugging your Gatling scripts.

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Applications are becoming more and more dynamic, with every month or even every week new
features being added or split out. Traditional application architectures have proven a nightmare to
build such dynamic systems in a reliable and fast way. Therefore, the architecture of applications is
moving more and more towards a microservice architecture.
Additionally, the high amount of users requiring different parts of the application backend requires a
more flexible approach then traditional virtualized servers. To this end, container based service
hosting has found a strong penetration in the market.
This session will discuss the approach of both methods, their similarities and their coupled and
synchronous rise in the market.

Discuss the future of Jakarta EE with the main people behind it!

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MicroProfile, RxJava, React.js – what else do you need to build lightweight but robust reactive systems efficiently with open source tools? Maybe something for effective data processing and distributed persistence? You can have it with Kafka and Hazelcast. Now let’s have a look at how to assemble all together in almost no time, using Payara Micro. You’ll learn how to use a couple of simple tools to build a highly efficient, scalable and robust system that can be evolved continuously to meet rapidly changing needs and increasing loads.

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Do you want to know how to build modern and scalable applications, while focusing on its business value? You’ll learn how to develop an agile evolutionary architecture which allows delaying unnecessary technical decisions until the time it’s safe to make them. MicroProfile features will get us started quickly. Start simple and easily refactor to improve the important parts later. Open source implementations of MicroProfile like Payara Micro add further flexibility; it can range from simple messaging to Apache Kafka or Amazon SQS for high performance messaging; from simple config files to distributed config. Come to learn how to think flexibly and adapt to the future.

In a live demonstration, you’ll see how an example application can be evolved gradually to deliver business value quickly and how to add new features later. You’ll learn how to evolve the application according to changing requirements without creating a ball of mud in the future.

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The topic includes basic and gentle introduction to Apache Kafka bundled with a live demo. For those that love to experiment and make their hands dirty. There will be a GitHub project including a dockerized infrastructure – Kafka and Zookeeper. All this will be followed by some real world Kafka stories from the kitchen.

Discuss the future of Jakarta EE with the main people behind it!

Slides

Create you very first Helidon-SE and Helidon-MP microservice!

Come learn about developing microservices using Helidon. Helidon is an open source project led by Oracle. Helidon contains a collection of Java libraries for building microservices. In this session we will talk about two programming models supported by Helidon: lightweight, functional model using JDK as runtime for those wanting less “magic” and Microprofile for those wanting inversion of control and familiar Java EE APIs. We will show how to quickly create your first Helidon application which uses both programming models.

Coroutines is a new feature in Kotlin. It allows for writing asynchronous code almost just like if it was regular/synchronous. This makes coroutines a great alternative to existing approaches for writing asynchronous applications.

In this session, I’ll show how coroutines work in Kotlin. You’ll learn about new syntax and implementation details. You’ll find out about the differences between coroutines-based and reactive-based solutions. You’ll also see a sample Spring-based application which uses coroutines.

In the latest years, there has been some push-back against frameworks, and more specifically annotations: some call them magic. Obviously, they make understanding the flow of the application harder.

Spring and Spring Boot latest versions go along this trend, by offering an additional way to configure beans with explicit code instead of annotations.

It’s called functional, because it moves configuration from objects to behavior. This talk aims to demo a step-by-step process to achieve that.

In the end, the demo application will run without any annotations at all using only declarative configuration, thanks to a new initiative called Spring Fu.

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The Java API allows a lot: sending packets over the network, compiling code, etc. If you put an application in an production environment, you need to make sure it doesn’t do more than it’s supposed to do.
Consider a Java application in a private banking system.

A new network administrator is hired, and while going around, he notices that the app is making network calls to a unknown external endpoint. After some investigation, it’s found that this app has been sending for years confidential data to a competitor (or a state, or hackers, whatever). This is awkward. Especially since it could have been avoided.

Code reviews are good to improve the hardening of an application, but what if the malicious code was planted purposely? Some code buried in a commit could extract code from binary content, compile it on the fly, and then execute the code in the same JVM run…

By default, the JVM is not secured! Securing the JVM for a non-trivial application is complex and time-consuming but the risks of not securing it could be disastrous.

In this talk, I’ll show some of the things you could do in an unsecured JVM. I’ll also explain the basics of securing it, and finally demo a working process on how to do it.

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Self-organizing scrum teams are just not enough! As per the Agile Manifesto “The best architectures, requirements, and designs emerge from self-organizing teams.”, which is true. According the Conway’s law it is also true the opposite, every great team and working smooth is not possible without great architecture.

Microservices and practices like DDD, Event sourcing and CQRS are the answer of enabling the Agility. In REWE Digital we have learned a lot from these practices and we want to share the lessons learned, showing also some real examples, of course everything is Java based. The whole stack is super impressive, we use Spring boot, Apache Kafka and many more.

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So, your system is well designed and thoroughly tested. It should run in production smoothly, shouldn’t it? If only it did! Alas, incidents happen.

Sometimes the reason is as simple (and embarrassing) as an edge case leading to a NullPointerException. But sometimes it’s really hard to understand the issue. You cannot believe it can ever happen! Yet it does. And after long hours of drilling in, you finally have an “aha! moment”:
A well known, widely used library gets stuck in…
An entire JVM crashes just because of…
It appears to be an explosive combination of your Cloud provider policies and…
A JVM setting, tweaked a few years ago…

No spoilers! Come and listen to four real stories of how “wonders” (not to say “nightmares”) which occurred in the production systems got investigated and how they have driven design or process improvements in our company.

Slides

So, your system is well designed and thoroughly tested. It should run in production smoothly, shouldn’t it? If only it did! Alas, incidents happen.

Sometimes the reason is as simple (and embarrassing) as an edge case leading to a NullPointerException. But sometimes it’s really hard to understand the issue. You cannot believe it can ever happen! Yet it does. And after long hours of drilling in, you finally have an “aha! moment”:
A well known, widely used library gets stuck in…
An entire JVM crashes just because of…
It appears to be an explosive combination of your Cloud provider policies and…
A JVM setting, tweaked a few years ago…

No spoilers! Come and listen to four real stories of how “wonders” (not to say “nightmares”) which occurred in the production systems got investigated and how they have driven design or process improvements in our company.

Slides

Cloud environments provide everything you need to develop a conventional application as a Service, completely obscuring the underlying infrastructure. This style of software development is called ’Serverless’ development.

This could be the holy grail that saves development teams from maintenance and platform/server dependence. Many development teams are in the process of maintaining a monolithic application and are planning to migrate this application to a Serverless solution for this particular reason. But is this a valid reason in the context of the monolith?

In this talk we will go through a brief history of how we got here, and look at the steps that need to be taken when you are considering such a migration. I will provide the insights from my own experience so far. Building a Serverless solution is completely different from conventional application development, which raises a ton of questions about whether this is a suitable replacement for the monolith. Development teams need to be aware of both the technical and cultural impact on their team and even the company itself before initiating the migration.

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In today’s world it’s no longer enough to build systems that process big volumes of information. We now need applications that can handle large continuous streams of data with very low latency so we can react to the ever-changing environment around us. To efficiently handle such problems we need to deploy a stream processing solution. During the talk we’ll explore one of the most popular frameworks for stream processing – Apache Flink. We’ll see what unique capabilities it provides and how they apply to some real world problems. And we’ll also explore how it works under the hood and how to get the scalable and fault-tolerant stream processing that Flink provides.

Slides

1. Introduction of EIP, Camel, OSGi and Blueprint
2. Installation and integration of Eclipse IDE, BND and Karaf
3. Explanation of five of the most powerful and feature-rich EIP
4. Working examples on:
   • Aggregator EIP
   • Splitter EIP
   • Routing Slip EIP
   • Dynamic Router EIP
   • Load Balancer EIP

This talk looks at the latest features in Apache Groovy 2.5, and 3.0. This includes new AST transformations, the new macros feature, the new Parrot parser and a myriad of other new miscellaneous features in the libraries and tools.

The talk outlines the roadmap for how the new features are being rolled out and the system requirements for each version including the levels of support for JDK 9+. The talk is example rich highlighting how to use Groovy with other commons libraries and projects. You should attend if you want to hear about the latest happenings with the Apache Groovy language or want to see how it can make you more productive when using other projects in combination with Groovy.

Slides

1. Introduction of EIP, Camel, OSGi and Blueprint
2. Installation and integration of Eclipse IDE, BND and Karaf
3. Explanation of five of the most powerful and feature-rich EIP
4. Working examples on:
   • Aggregator EIP
   • Splitter EIP
   • Routing Slip EIP
   • Dynamic Router EIP
   • Load Balancer EIP

The market hype in artificial intelligence (AI) is pushing more and more software vendors to introduce AI capabilities in their products and offered services. In this talk, I will share interesting technology use cases and my experience in developing intelligent solutions for some of the biggest enterprises. The presentation will cover the areas of natural language processing, knowledge bases, and machine learning. In each domain I will briefly describe the technology challenge, the existing Java software ecosystem with simple to understand code examples. You should join this session if you want to see the high-level landscape of AI technology, the relevant Java libraries and frameworks + simple to reuse code examples.

In this lecture, Stanimir will share good practices in the problem-solving process. Based on his personal experience, he would give advice on how to gain the confidence we need, when we are looking for a solution. How to build and analyze a set of alternatives, which approach towards the problem should we choose and many more aspects, regarding the problem-solving process are to be covered by Stanimir.

For the past 9 months myself and a team of fearless software engineers, devops experts and software architects have been working on a transformation project for a large enterprise. Our goal is to strangulate a monolith enterprise application, developed in the last 10 years into a modern microservice based mesh.

In this topic we will look into the challenges posed by the project’s requirements and the overall architecture that we have defined. We will also dive deeper into the principles we followed for performing the migration from monolith to microservices. And finally, we will explore how we setup the container infrastructure and used a modern state of the art platform for managing a service mesh build on top of Redhat Openshift Container Platform

Discuss the future of Jakarta EE with the main people behind it!

Slides

JNoSQL is a framework and collection of tools that make integration between Java applications and NoSQL quick and easy — for developers as well as vendors. The API is easy to implement, so NoSQL vendors can quickly implement, test, and become compliant by themselves. And with its low learning curve and just a minimal set of artifacts, Java developers can start coding by worrying not about the complexity of specific NoSQL databases but only their core aspects (such as graph or document properties). Built with functional programming in mind, it leverages all the features of Java 8. This session covers how the API is structured, how it relates to the multiple NoSQL database types, and how you can get started and involved in this open source technology.

Slides

Security concepts incorporated in the Java platform and major frameworks like Spring, Java EE and OSGi are typically difficult to grasp and understand in depth. The same applies for Java concurrency utilities and a tool called Java Concurrency in Practice was created to address this issue a few years back and following its trail a similar tool called Java Security Animated is aiming to lower the entry barrier to the security portfolio of the Java platform. In this tool we will have a journey in the security world of the platform using Java Security Animated.

Idea behind the tool is derived with a consent by the creator of Java Concurrent Animated (Victor Grazi) and was presented at Java2Days 2012.