What do you mean by term “Syntactic Sugar”?

For many of us term Syntactic Sugar could be something out of this world and the term is too much heavy that anyone would wonder about this alien word. But many times the concept behind such terms is very simple. Now let’s make this word easily understandable. In such cases, I always split the term into separate words and try to understand the meanings of individual words in programming world prior to understand actual meaning the term.

So below is the diagram how I understand this term, Continue reading “What do you mean by term “Syntactic Sugar”?”

Introduction to Functional Programming

Before we understand practical capacities of Scala language or attempt to learn core ideas of lambda expressions in Java, it is more crucial to understand the concept of Functional Programming first.

Most of the popular programming languages (like C, C++ and Java) are primarily created to follow the methodology of Imperative Programming, which implies that programmer generally write a code block (sequence of statements) which will change the state of the program(value of the variables) as each line is executed step by step. Continue reading “Introduction to Functional Programming”

5 Steps to Setup Static IP And FQDN to CentOS Machine

Most of the when we start to setup any kind of cluster (for Hadoop, Spark etc…) from scratch, we as a beginner often  face certain problems while performing steps (like setup Static IP address or setup FQDN) after installation of Linux flavour OS on our VM or Machine. There are very less forums where you can get all of these bazics steps together along with full understanding. Here I have tried to explain you the process of setting up static IP address and FQDN (Fully Qualified Domain Name) in 5 steps. All of these steps are tested on VM/Machine available straight after minimal installation of CentOS 6.4. Continue reading “5 Steps to Setup Static IP And FQDN to CentOS Machine”

4 Debug Points to check why your Keyless SSH is not working

Setting up keyless SSH is quite easy on CentOS but still sometimes there are chances that after following all the steps mentioned in How to setup Keyless SSH with non root users in CentOS post it is still not setup properly. There could be many possibilities as a root cause like improper permissions, invalid configuration etc. I have mentioned mainly four debug points which you should follow if your keyless ssh setup seems to be misbehaving. Continue reading “4 Debug Points to check why your Keyless SSH is not working”

How to setup Keyless SSH with non root users in CentOS

While setting up Hadoop or Spark Cluster, primary objective is always to setup keyless SSH between master and slave machines after you set Static IP and FQDN properly. First of all lets understand why it is required to setup passwordless SSH is required for any distributed cluster. Continue reading “How to setup Keyless SSH with non root users in CentOS”

2 Ways of installing Java 8 on CentOS

Installing Java on CentOS is one of the easiest exercise ever. However, I’ll let you know two different ways in which Java can be installed on CentOS. We’ll take latest version of Java which is Java 8. Even you can combine all following steps in one shell script and can simply execute that shell script in order to install Java/JDK. Following steps are performed using root user you can also execute the steps with non root user having sudoer rights. Before moving towards installation process I have assumed that CentOS has wget command installed. If not than install it using below step. Continue reading “2 Ways of installing Java 8 on CentOS”