Message Authentication

Cryptographic Message Authentication explained in details. Suitable for Beginners with Java examples...

March 29, 2016 · 6 min · Alexander Holbreich

Symmetric-key cryptography

Symmetric Cryptography explained in details. Suitable for Beginners with code examples...

March 17, 2016 · 11 min · Alexander Holbreich

Installation and Configuration of Sonatype's Nexus

There are many people using Maven or Ant for years but do no use a repository manager like Nexus or Artifactory. This article describes how easy it is to setup and run your Nexus - an Artifact Repository Manager. Motivation One of the greatest features of maven is dependency management. Most of maven builds produces artifacts, also projects, of course, depend on another artifact (e.g java jar files) in different versions and configurations....

October 12, 2012 · 4 min · Alexander Holbreich

Maven Basics

This article covers basic concepts of maven self. Lastly i described how to setup maven. Introduction Maven is a project management framework (or tool). This definition is relatively abstract and doesn’t justifies the richness and of Maven. Let me try to describe maven by looking at the central idea and it was the adoption of best practices/principles (of that time): Convention over configuration Declarative execution Reuse of build logic Coherent organization of dependencies Let' see how maven adopts these....

October 8, 2012 · 5 min · Alexander Holbreich

Apache Maven Installation

This article provides step by step tutorial of Apache Maven installation on linux. Motivation Apache Maven is Software Project Management and Configuration tool. Through it’s bride acceptance in the java-developer community it introduces some kind of unification and standardization in a structure of java Software projects. Long story short, every software project produces some artifacts (e.g .jar files). These are deployed, archived, copied, referenced and so on. Maven provides basic support for all kind of tasks like that....

September 26, 2012 · 2 min · Alexander Holbreich

Introduction to Apache Camel

Apache Camel is a versatile open-source integration framework based on known Enterprise Integration Patterns In order to understand what Apache Camel is, you need to understand what Enterprise Integration Patterns are. Much like the Gang of Four, Gregor Hope and Bobby Woolf authored the book Enterprise Integration Patterns (EIP) in which they described and documented a set of new patterns on how we design large component-based systems, where components can be running on the same process or in a different machines....

September 10, 2012 · 5 min · Alexander Holbreich

OSGi Bundles: Declarative Services

This post covers some basic OSGi concepts. Also I’ll present a Tycho example of service definition in declarative approach. Motivation to modules Slicing complex system in modules is the crucial approach for the complexity reduction1. Developing for JVM is by default developing in one code space. Modularization is supported by concept of packages and visibility levels. However these techniques seem to be very soft concepts, thus the teams building everything in huge weakly modularized code bases or try to utilyze additioan libraries and tools....

September 5, 2012 · 7 min · Alexander Holbreich

Oracle (sun) jdk console tools

Modern Oracle JVM versions are bundled with diagnostic tools. Here i’m going introduce the most prominent of them. First to mention is of course VisualVM which evolves even independently of jvm releases. VisualVM allows relative deep analysis and its comprehensive enough furthermore it’s open source tool. However it reaches limits when you have to work with java version prior to 1.5. (yes, sometimes things changes very slowly ;) Also it’s often the case that its not easy to connect over RMI remotely to productive machines, therefore its never a bad thing to be familiar with console tools modern jdk and JVM provided with the installation....

August 2, 2012 · 7 min · Alexander Holbreich

Release your entities

This post elaborates on an interesting Architecture bug (was made long time ago by unmet team) and the fix for it. To sum up it’s about entities purification out of the Persistence Context overhead when you need to use them outside of the container, serialize them and send them over RMI,SOAP and other protocols to other JVMs. The Problem You may found yourself in a situation where you don’t have DTOs (for whatever strange reason), there existing object-graph is large but you need to use entity objects outside of the managed scope....

February 22, 2012 · 6 min · Alexander Holbreich

JBoss 7 setup on debian linux

This is a short step-by-step setup guide for JBoss 7.0.2 on Linux ((Debian). Nowadays there is still no official Debian package for JBoss 7 out there, so we have to do a couple of steps manually. 1. download and prepare Start by download the currently available version (7.0.2) of the JBoss 7. #Web Profile version download. wget http://download.jboss.org/jbossas/7.0/jboss-as-7.0.2.Final/jboss-as-web-7.0.2.Final.tar.gz Extracting files to the final location using tar. tar zxvf jboss-as-web-7.0.2.Final.tar.gz -C /usr/local/ Now your JBoss 7 is placed inside /usr/local/jboss-as-web-7....

November 10, 2011 · 3 min · Alexander Holbreich