Do you want to know how to develop your skillset to become a Java Rockstar?

Subscribe to our newsletter to start Rocking right now!

To get you started we give you our best selling eBooks for FREE!


1. JPA Mini Book

2. JVM Troubleshooting Guide

3. JUnit Tutorial for Unit Testing

4. Java Annotations Tutorial

5. Java Interview Questions


and many more ....



Coordination in Akka

This is the fifth post in the series about integrating sync clients with async systems (1, 2, 3, 4). Here we’ll see how to manage the actor’s lifecycle, so our service can use the available resources efficiently. Lifecycle Actors, threads, objects, resources… All of them have different states during their lifetime. Some of those states are internal and they shape ...

Read More »

Back to the CompletableFuture: Java 8 Feature Highlight

CompletableFuture vs Future: going async with Java 8 new features Java 8 was released on March 2014 and arrived with a long list of new features. One of the less talked about, extremely useful yet misunderstood features is a brand new and improved extension to the Future interface: CompletableFuture<T>. In the following post we’ll present an overall view of CompletableFuture, ...

Read More »

Ensuring Containers Are Always Running with Docker’s Restart Policy

Getting a notification that Docker containers are down in production is one of the worst ways to spend your night. In today’s article, we’ll discuss how to use Docker’s restart policy to automatically restart containers and avoid those late-night notifications. What Happens When an Application Crashes? Before we get started with Docker’s restart policy, let’s understand a bit more about ...

Read More »

NetBeans Java EE Tip #9: Create JSF Application from Database

Do you need to create an database front-end very quickly?  The NetBeans IDE allows one to develop a JSF application front end for a set of database tables very quickly, and with very little coding.  Now this tutorial is an oldie, but a goodie…and it is worth mentioning again for those who are not aware of it. First, create your ...

Read More »

Getting Started with Heron on Apache Mesos and Apache Kafka

Heron has been Open Sourced, woo! Heron is Twitter’s  distributed stream computation system for running Apache Storm compatible topologies in production. A Heron topology is a directed acyclic graph used to process streams of data. Heron topologies consist of three basic components: spouts and bolts, which are connected via streams of tuples. Below is a visual illustration of a simple topology: Spouts are ...

Read More »

Scala Notes – Futures – 1

Almost all modern programming languages have a Future-Promise idiom for concurrent programming. I don’t intend to bore you with why we need higher level of concurrency abstractions. Instead, in this post, we’ll cut to the chase and discuss only about Scala’s approach to Futures. A scala.concurrent.Future is a representation of a value that is yet to be realized. This value ...

Read More »

The Building Blocks of Your First Bot

The world of bots who can intelligently converse continues to build momentum. We’ve seen the opening up of the Facebook Messenger and LINE platforms, as well as improvements to the existing Telegram platform. In addition to new and improved platforms, the Kik bot store has opened, and Slack is making submission to their app store a product priority. While messaging ...

Read More »

Why Microservices Should Be Event Driven: Autonomy vs Authority

I’ve been working on a series of articles showing how to build microservices using an event-driven approach (which IMHO is the only real way to build microservices :) or… any complex distributed architecture). I’ll explore DDD, CQRS, Event-sourcing, event streaming, complex-event processing and more. I’m using a reference monolith application based on Java EE that uses all the typical Java ...

Read More »

Aspect Oriented Programming with Spring Boot


On a previous post I provided a simple example on how to achieve aspect orientation in spring by using a ProxyFactoryBean and implementing the MethodBeforeAdvice interface. On this example we will learn how to achieve aspect orientation by using Spring boot and Aspect4j annotations. Let’s start with our gradle file. group 'com.gkatzioura' version '1.0-SNAPSHOT' apply plugin: 'java' apply plugin: 'idea' ...

Read More »

Want to take your Java skills to the next level?

Grab our programming books for FREE!

Here are some of the eBooks you will get:

  • Spring Interview QnA
  • Multithreading & Concurrency QnA
  • JPA Minibook
  • JVM Troubleshooting Guide
  • Advanced Java
  • Java Interview QnA
  • Java Design Patterns