Discover

Overview of changes of classloaders in Java 9.

java9-classloaders

All programming workshops prepared by me.

workshops

java11-lambda-patterns

Functional programming patterns in java.

Exploring basic features of Async in Spring.

spring-boot-async

Overview of vavr Validation API.

java11-vavr-validation

Groovy closures overview: owner vs delegate vs this.

groovy-closure-owner-delegate-this

Introduction into functional programming free structures: free monads, free monoids, free applicatives.

jit-notes

JIT in details.

scala-cats-free-monad-workshop

Java reactive streams workshop: basic implementations of Publisher, Subscriber, Subscription and Processor.

java12-introduction-to-reactive-programming-workshop

Overview of how to to construct modern enums using lambda.

java11-enum-clean-code

Example of well implemented Spring Data Specification.

spring-data-specification

Overview of vavr Try API.

java11-vavr-try

Exploring basic features of Spring AMQP.

rabbitmq

SQL, JPQL, HQL & JPA Criteria API training

jpa-criteria-api

Simple implementation of Reader Functor.

java11-category-theory-reader-functor

Introduction into fs2, newtype and refined types.

scala-zio2-fs2-refined-newtype-workshop

WebSocket protocol summary.

js-nodejs-websocket-workshop

JavaScript

spring-data-jpa-queries

The main goal of this project is to show basics of constructing queries using Spring Data and its repositories.

Introduction to tagless final with cats and to http4s middleware.

scala-cats-tagless-final-http4s-middleware-workshop

Introduction into functional dependency injection with Reader monad.

scala-cats-functional-dependency-injection-workshop

Exploring basic features of groovy to produce DSL.

groovy-dsl

Exploring basic features of exception handling in Spring (ControllerAdvice).

controller-advice

Simple example of LazyInitializationException.

hibernate-lazy-initialization-exception

Introduction into pkcs11 and integrations with hsm using softhsm.

cryptography-hsm-workshop

Example of mixing stream with completable future using composition.

java11-stream-composing-completable-future

Basic examples of compare and swap.

java-concurrency-compare-and-swap

Basic example of phantom reference in Java.

phantom-reference

Proof that java Optional is not a functor, but vavr is.

java11-category-theory-optional-is-not-functor

Short introduction to happens-before, volatile and jcstress.

java8-concurrency-jcstress-happens-before

Simple example of real-life problem solved with Semaphore.

java11-concurrency-semaphore

Simple configuration of Gradle build cache.

gradle-build-cache

The main goal of this project is to show how getOne works internally.

spring-data-getone

java11-vavr093-option-workshop

Vavr Option workshop.

Introduction to streaming using zio (ZStream).

scala-zio2-zstream-workshop

Introduction to pure functional programming using effects with zio, http4s, fs2 and doobie.

scala-http4s-zio-doobie-workshop

How to traverse stack in java 8 environtment.

java8-stack-stackwalking

Java implementation of Bartosz Milewski examples and challenges of Kleisli Category.

java11-category-theory-kleisli-category

Short introduction to the http methods in the spring context.

java13-spring-crud-http-methods-workshop

Summary of new features in each java version (since JDK8).

java-feature-timeline

java9-string-concat

Overview of java String concatenation compilation: java 8 vs java 9.

Exploring basic features of ModelMapper.

model-mapper

Projects concerning java stack, frames.

java-stack

gradle-integration-test-task

The main goal of this project is to provide simple implementation of integration test task for Gradle.

Short introduction into BFS, DFS and A* algorithms with case-studies.

scala-algorithms-bfs-dfs-astar-workshop

Introduction to Spark Batch processing.

big-data-scala-spark-batch-workshop

Summary of Collectors.groupingBy API.

java11-collectors-groupingBy

Implementation of stream's map / filter using flatMap.

java11-stream-map-filter-implementation-using-flatMap

Spring Boot configuration of h2 console.

spring-boot-h2-console

Covariance, invariance, contravariance overview of collections in Java 11, vavr, guava.

java11-covariance-contravariance-invariance

Overview of StackWalker API in java 9.

java9-stack-stackwalking

Proof and implementation of coproduct in Set category.

java11-category-theory-set-coproduct

Implementations of basic GOF design patterns in a more functional way, using function and streams.

java15-design-patterns-made-functional-workshop

Overview of java regex API.

java11-regex

Simple solution to producer - consumer problem.

java11-concurrency-wait-notify-producer-consumer-problem

Overview of basic features of ComponentScan

springboot-component-scan

Exploring basic features of @Audited from Hibernate Envers.

envers-audited

Simple example of hash function.

hash-function

Non-blocking single threaded implementation of server using java.nio: polling.

java12-nio-non-blocking-polling-server-workshop

Implementation of product in total poset category.

java11-category-theory-total-poset-product

design patterns and real-life examples

designPatterns

Why java streams laziness needs pure functions.

java-streams-laziness-needs-pure-functions

Java Exceptions: localizedMessage vs message.

exceptions-localizedMessage-vs-message

Implementation of trampoline in Java.

java11-trampoline-implementation

The main goal of this project is to show configuration of Basic Authentication in Spring Security + Spring Boot environment.

spring-security-basic-auth

Java 11 Predicate Interface.

java11-predicate

Examples of vavr function lifting.

scrum-notes

java11-vavr-function-lifting

Overview of delegate, mixin and trait in groovy.

groovy-delegate-category-mixin-trait

Explicitly invoking default method from enclosing interface.

java11-invoking-default-method

Overview of how java compiles lambda.

java11-lambda-compilation

Showcase of StringJoiner API.

java11-StringJoiner

Why throwing exceptions in Java is expensive?

java11-exceptions-throwing-exceptions-is-expensive

It is often better to provide in memory repository than h2 during tests.

spring-test-database-mock

Simulation of birthday paradox.

java11-birthday-paradox

Exploring basic features of services in Java 9 modularity system.

java9-modularity-services

Overview of PECS principle.

java11-pecs-principle

Gentle introduction into kotlin, DI containers and spring batch.

kotlin-DI-spring-batch-workshop

Kotlin

java-this-escaping-constructor

Leaking this reference from constructor.

java11-enumset

Overview of EnumSet API.

Configuration of CI / CD (travis, heroku).

travis-heroku-config

Overview of groovy trait.

groovy-trait

Short introduction to the most important java incubator projects.

java-incubator-projects

completable-future

Exploring CompletableFuture API.

Implementation of product in powerset poset category.

java11-category-theory-powerset-poset-product

Simple example of real-life problem solved with Exchanger.

java11-concurrency-exchanger

Exploring basic features of Gradle's Tasks.

gradle-tasks-example

Non-blocking implementations of server using java.nio selectors: single and thread pooled.

java12-nio-non-blocking-selector-server-workshop

The main goal of this project is to show differences between invokespecial vs invokevirtual.

java-bytecode-invokespecial

Functor, Monoid, Monads in practice.

scala213-functional-programming-functor-monoid-monad-workshop

Example of CyclicBarrier in java.

java11-concurrency-cyclicbarrier

java11-vavr093-try-workshop

Vavr Try workshop.

Simple implementation of command design pattern using lambda and comparison to the old approach.

java11-lambda-command-pattern

Implementation and proof that Set category is semiring with product and coproduct.

scala212-category-theory-set-semiring

Simple example of composing functors using Cats.

scala212-cats-category-theory-composing-functors

Simple introduction to Helm basics.

helm-workshop

Kotlin

java8-map-functions

Overview of Java 8 additions to Map interface.

Introduction to terraform basics.

terraform-basics-modules-workshop

HCL

java-notes

Collection of papers written by me on important java features: memory model, JIT, future of JVM, etc...

100

java11-vavr-option

Overview of vavr Option API.