java basics

Git Essentials Crash Course

Posted by Alexius Dionysius Diakogiannis on in Open Source, Others

Introduction

This is not Java but several newbie developers ask the same question, how to use GIT and how does GIT works so here it goes…

Have you ever work in SVN? Well forget everything you know and lets start over 🙂

What is a GIT repo?

In general there are two mirror repos. Your local repo and the remote repo. Yes TWO REPOS. Everyone in the team has an actual copy of the whole repo so even if your remote server dies you can set it up again and just push (spoiler) your repo to the repote server.
Continue reading “Git Essentials Crash Course” →

Can/Should I use parallel streams in a transaction context?

Posted by Alexius Dionysius Diakogiannis on in JEE
Java

Introduction

To make a long story short, you should not use transactions within a parallel stream. This is because each thread in the parallel stream has its own name thus it does participate in the transaction.

The Streams API is designed to work correctly under certain guidelines. In practice, to benefit from parallelism, each operation is not allowed to change the state of shared objects (such operations are called side-effect-free). Provided you follow this guideline, the internal implementation of parallel streams cleverly splits the data, assigns different parts to independent threads, and merges the final result.

Continue reading “Can/Should I use parallel streams in a transaction context?” →

The Transient Keyword in Java and Its Use

Posted by Alexius Dionysius Diakogiannis on in JEE, Others

This article is originally posted by me in Java Code Geeks with title

The Transient Keyword in Java and Its Use

I recently came a cross in a study project of one of my friends that are studding the basics of programming in Java some forgotten sensitive information printed in text files and remembered the transient keyword in Java.

The transient keyword in Java plays an important role in terms of security and can be very useful in “accidents” like the one above as it will prevent the transmission of sensitive information like for example passwords to files, JSON messages etc that will require serialization.

To cut the long story short, if you define any variable as transient, it will not be serialized unless you define it as static or final.

Lets see some examples bellow. Continue reading “The Transient Keyword in Java and Its Use” →