I have been working in the enterprise Java field for a while now and periodically friends and colleagues ask me for help and advice. Over time I have collected several of their questions and would like to share them together with my view and experience on the subject. Questions vary from how to choose between popular Java frameworks, benefits and drawbacks of using ORM, designing REST APIs, performance considerations, etc. Some of them are specific for the Java field, while others are general topics for enterprise applications.

The topic covers best practices and common mistakes developers experience while designing code and corresponding tests taking into account TDD approaches.

The topic covers best practices and common mistakes developers experience while designing code and corresponding tests taking into account TDD approaches.

The presentation will introduce the audience to the microservice architecture and how it is different from a monolithic one. It will focus on the different components that are necessary for a microservice architecture such as discovery service, configuration service, api gateway and others. For each one of the components will be highlighted why they are important for this type of architecture and how to implement them with Spring Boot and Netflix stack.

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Java is everywhere. According to Oracle it’s on 3 billion devices and counting. We also know that Java is one of the most popular vehicles for delivering malware. But that’s just the plugin right? Well maybe not. Java on the server can be just at risk as the client. In this talk we’ll cover all aspects of Java Vulnerabilities. We’ll explain why Java has this dubious reputation, what’s being done to address the issues and what you have to do to reduce your exposure. You’ll learn about Java vulnerabilities in general: how they are reported, managed and fixed as well as learning about the specifics of attack vectors and just what a ‘vulnerability’ actually is. With the continuing increase in cybercrime it’s time you knew how to defend your code. With examples and code this talk will help you become more effective in tacking security issues in Java.

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Java – it’s on billions of devices. We think it powers the world.  Others disagree.

In this talk we’ll examine a few of the reasons why some developers believe Java is being left behind by younger (or at least different)  programming languages.  We’ll show where the claims make sense and debunk some of the more outrageous slander.  We know the future of Java includes a more polyglot world so we’ll help you understand with practical advice where Java shines today and where you might be better using something else.  We’ll also cover the challenges that all runtimes have in the new era of Cloud and how the Java community is leading the way in evolving Java into becoming the Cloud runtime of choice.

This talk will help you become more informed when dealing with those inevitable language cage fights around the water cooler.  You’ll be able to refute the fake news and replace it with clear facts.   Vote for Java – you know it makes sense.

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Fed up of writing getters and setters? Or opening a big class and trying to find the important stuff inside, but feeling lost in the forest of boilerplate?

Project Lombok is an open source project that tries to help developers to get rid of as much as possible of that. It presents a set of annotations for different purposes. For example you can annotate your class/field with @Getter and lombok will generate for you getters for all your fields/field. @EqualsAndHashCode will help you by generating code for your equals and hashCode. And there are other annotations that help with other boring tasks.

In this presentation I will demonstrate how easy is to reduce the amount of code you have to write for some simple tasks using annotations provided by Project Lombok. I will explain how exactly works this technology. I will demonstrate how to add support for your annotated code in your favorite IDE so that you be able to use code completion and call methods that are not actually there in your source code.

Open Liberty is a newly Open Sourced, EPL licensed, Java application server. It supports the full Java EE and MicroProfile programming models and its lightweight, composable design makes it the ideal runtime for Cloud Native and Microservice-based applications. With the aid of demos, this session with take you through a first look at Open Liberty. Where to get started, core concepts, capabilities, how to install, configure, deploy, and more.

Feature flags (a.k.a. feature toggles) are a set of patterns that enable dev-teams to deliver features to users rapidly and safely.

This talk leads you on a journey with a dev team as they adopt feature flags, covering what they are, why they’re helpful, and how to use them successfully. Along the way, you’ll discover that feature-management covers a broader set of use cases than you might initially think.

We’ll see how different types of toggles can be categorized and learn why it’s important to manage the various types of toggles in different ways, even if they share a common underlying implementation. We will discuss different ways to store toggle configuration and enabling strategies, and how to prevent them from getting out of control.

As a practical demonstration, a real-life Java web application using an open-source solution (Togglz) will showcase how feature flags were employed while transitioning between its development stages.

Finally we’ll share best practices from the industry and tips on how to succeed with feature flags in the age of microservices.

How well tested is your system? How do you measure it? Code coverage can give you an answer, however how well are tests actually written, and… can we trust them?

As a developer: How do you know that even the smallest change to the code will make at least a test fail?

As someone with a management role: How do you handle big projects with high quality requirements, when developers can write a lot of unit tests which have no assertions whatsoever? (and yes, the test coverage is very high)

Mutation testing is a method to check the quality of your unit tests and show more reasonable and useful code coverage reports. This session will describe the main idea and concepts of mutation testing, and some technical means to implement it in Java/JVM.

Finally, a live example will follow, with the use of PIT Mutation Testing framework – first illustrating the concepts, and then showing results of testing a more complex Java web application.

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Performance Monitoring tools like Performance Co-Pilot (PCP) existed almost longer than the World Wide Web. It was developed in the early 90s by SGI. Parts were made available open source from 2000 on, which led to a further spread of the tool. In recent years an active community formed and a variety of new features and enhancements were added. PCP is now part of Red Hat and SuSE Linux Enterprise editions and included in many other Linux distributions. Versions for other Unix variants, OS X and Windows also exist. This session compares popular Open Source Monitoring Tools like Performance Co-Pilot, StatsD, Dropwizard Metrics, Prometeus and MicroProfile Metrics. How they each support Containers or Virtualization, share data with IT monitoring systems like Nagios or Zabbix, or process analyze and visualize it via Carbon, Graphite or Grafana/ElasticSerch.

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This session will give you a brief overview of how Tenkiv and Nexus Brain use Kotlin and Physikal/JSR 363 to calculate the optimal usage of alternate energy sources and control solar power systems used for making clean water anywhere from Flint Michigan to Afghanistan.

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Kotlin came out as a result of pragmatic efforts, aimed to target problems encountered by developers during real-world tasks. It is an open-source industrial-strength language designed by JetBrains.

Thanks to “Full Java interoperability” it can blend easily in your Java projects. It means, from the day one you can start taking advantage of, the newly introduced language leveraging your java knowledge, use existing libraries and gradually evolve your code base to migrate to Kotlin.

In this talk, we will take a code-centric approach on how to get started with Kotlin; take a look on various features such as: null safety, smart cast, extension functions, data classes, let, etc. in order to improve code readability and maintainability.

We will also decompile some Kotlin code to get better understanding of what happens under the hood.

Last but not the least, we will build a demo application in Kotlin and backed via a spring-boot.

Java Memory Model is an interesting area of multi-thread programming. It describes how threads interact through memory and what behaviours are allowed in concurrent execution. Most of java developers are familiar with mutual exclusion and synchronized keyword but sometimes we forget that beside mutual exclusion we also have to care about memory visibility.

The talk will introduce number of examples to help understand JMM. It will use OpenJDK Java Concurrency Stress tests framework (JCStress) to validate the results.

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It’s been 15 years since the Agile Manifesto was signed and several methodologies were raised ever since. There is almost no developer nowdays that haven’t adopted at least one of the Agile principles and uses them in everyday work or even private life. Some has even done improvised versions which work according their needs.

The question that’s been around these past years is if the Agile is old enough to become past and what’s the next big thing, is it a time to call it Post-Agilit period and what that means. What has or needs to change in order to abandon the old and become the Post Agilit followers.
Lots of teams already claim themselves as Post-Agility pioneers and some new ideas of methodologies have been introduced. I’ll try to bring an overview of some of them and bring you some thoughts that might help answering the above questions.

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Bosch Software Innovations’ IoT platform allows you to realize innovative business models in the Internet of Things (IoT) and cross-domain applications. The Bosch IoT Suite is a flexible software platform based on open standards and open source. Its cloud services meet the requirements typical of IoT projects. Software developers can quickly set up prototype applications before implementing them, deploying them within minutes, and operating them at high availability.

In addition to the cloud services, the device management capabilities of the Bosch IoT Suite can also be used stand-alone and on premise. For the realization of gateway-based IoT scenarios our market-leading and OSGi-based ProSyst Gateway Software is ready to be used in different domains.

Part of the large CXP Group, PAC analyzed 14 companies in the field of IoT device management. The study looked at device management and IoT data integration for the comprehensive and centralized management of connected devices. In particular, it focused on cloud-based device management, the networking of a large number of different devices, and IoT data integration (iPaaS).

The PAC analysts rated Bosch Software Innovations as above average in several categories, noting in particular the company’s strong strategic focus on the Internet of Things.In addition, they designated the Bosch IoT Suite’s device management the leader in the European market and awarded it the “Best in Class” seal, thanks in part to the company’s strong references.

Both ProSyst Gateway Software and Bosch IoT Suite’s device management are developed from our team in Sofia.

https://www.bosch-si.com/iot-platform

We will take a look at what actually a GPU is. In the beginning we will have a small introduction on how it evolved throughout the years. We will see how it can be utilized in the Java world. There will be a small intro to the world of OpenGL. And then we are going to move to CUDA and OpenCL technologies for general purpose massive computations on regular desktops or cloud machines. We will see what are the advantages and drawbacks, how can we easily use Java to utilize the GPUs in the cloud.

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Terraform has changed the way many organizations deploy to the cloud. With a clear configuration language you can manage countless services (providers in Terraform) and ensure they are kept in sync with your deployment needs. Learn how to build out some of the most common patterns and infrastructures against AWS, and start writing your infrastructure as code today.

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This presentation will focus on the challenges we faced when we tried to document our product – the Nemesis Ecommerce Platform. It will show you the different approaches we tried and why we actually decided to go for Asciidoctor and SpringRESTDocs. This presentation is not only a deep-dive into SpringRESTDocs functionalities, but it will also show you how we automated the whole process of documentation by extending SpringRESTDocs to produce our documentation widgets, specifically the rest-tester widget, how we let Maven pre-process all of that, and how we configured Asciidoctor to produce what is now our current documentation.

Learn how to scale your Continuous Integration and Continuous Delivery environment using containers. The Kubernetes project provides a container orchestration solution that greatly simplifies app deployments in large clusters and you can use Jenkins and Kubernetes together to run jobs on-demand.

Building and testing is a great use case for containers, both due to the dynamic and isolation aspects, but it increases complexity when scaling to multiple nodes and clusters.

Jenkins is an example of an application that can take advantage of Kubernetes technology to run Continuous Integration and Continuous Delivery workloads. Jenkins and Kubernetes can be integrated to transparently use on demand containers to run build agents and jobs, and isolate job execution. It also supports CI/CD-as-code using Jenkins Pipelines and automated deployments to Kubernetes clusters. The presentation will allow a better understanding of how to use Jenkins on Kubernetes for container based, totally dynamic, large scale CI and CD.

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During this talk Roman will give a detailed overview of Spring Rest Docs as well as demonstrate practical usages of it within a Spring Boot app with live coding. We will discuss the tradeoffs that developer has if s/he uses swagger as base framework and what benefits spring rest docs provides. Also, Roman will advise how to migrate your existing swagger’s project documentation into asciidoc format, extend it with tests and start using Spring Rest Docs.

After this session you will be ready to apply Spring Rest Docs at any project – a new one from the scratch or on existing one.

Spring Rest Docs has provided robust, flexible approach that is called Test Driven Documentation. It extends well known Red-Green-Refactoring from TDD with additional phase of building documentation on the fly.

This approach aligns 3 main components in your project – code base, integration tests and documentation and you are absolutely sure that your documentation is always up to date because it is generated from your tests. Furthermore it supports HATEOAS and provides lots of new features that are not available in Swagger.

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Anyone can do some code snippets using Spring Boot, but to become a master at it is quite different. Spring Boot has become a de-facto standard for the Java development community due to out-of-the-box functionalities following a principle “convention over configuration”, this makes that many developers miss some necessary conventions to build more scalable, resilient and secure applications. You’ll learn how to tweak Spring Boot’s configuration, monitor and health check your app, extend Spring Boot and its available plugins, a simple way to secure your application with practical examples.

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The shipping containers were introduced around 1830s and since then they play a crucial role in the modern society by providing efficient packaging, storage and transportation. Today we see the same revolution happening in the DevOps world with the adoption of container technologies like Docker. They allow us to package, distribute and run software in a scalable and efficient way. In this talk we’ll see how we can abstract the common problem we solve everyday when building scalable Java APIs with Docker into design patterns to create reusable solutions. We’ll explore the good practices of writing Java applications with Docker. Then we’ll see how each design pattern can be applied in real scenarios that address different concerns that a large system creates. We’ll see some real life implementations of those patterns and how they help us solve problems in scalable systems. By the end of the talk we’ll have a very powerful abstraction to tackle the everyday problems we face in building big and impactful systems.

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Java 9 has finally shipped! Will your application still work and are you ready for Java 9 modules? Java 9 modules (aka Project Jigsaw) is the biggest fundamental change to the Java runtime. Code that use Oracle/Sun private APIs will break. This session will cover the basics of Java 9 modules and also the current state of tooling. The ramifications to existing and legacy applications will be covered along with the steps you’ll need to take to harness the power of modules and write more maintainable systems.

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Testing Java EE applications has never been easier. In this session, you will learn how to perform integration testing using Arquillian and Arquillian Cube. Unlike unit testing, integration testing enables you to test large segments of the application in the application container with minimal effort. You’ll see how you can test EJBs including MDBs and also mock key part of a system to test exception handling. In addition, technique for testing client-side JavaScript code with the backend server will be covered. Between Arquillian, Docker, and mocking, complete testability for Java EE is possible.

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