Git Branching Tutorial for beginners

Git Branching Tutorial for beginners

Branching allows git to track multiple lines of development. This essentially allows you to have multiple versions of your project in development at the same time. For example, many projects will choose to have a stable master branch while new features or bug fixes are implemented in a development or testing branch. Once the project organizers are satisfied that the changes made in the development branch have reached the required level of maturity, they may choose to merge those changes into the master branch.

Read more

jq-logo

How to parse a json file from Linux command line using jq

The JSON (JavaScript Object Notation) format is widely used to represent data structures, and is frequently used to exchange data between different layers of an application, or by the use of API calls. We probably know how to interact with json-formatted data with the most used programming languages such as parsing JSON with python, but what if we need to interact with it from the command line, or in a bash script? In this article we will see how we can accomplish such a task by using the jq utility and we will learn its basic usage.

In this tutorial you will learn:

  • How to install jq in the most used Linux distributions or compile it from source
  • How to use jq to parse json-formatted data
  • How to combine filters using “,” and “|”
  • How to use the length, keys, has and map functions

Read more

radiolist-widget

How to use ncurses widgets in shell scripts on Linux

In this tutorial we will learn the basics of the dialog utility, in order to use ncurses widget in our shell scripts. We will see how to install dialog in the most used Linux distributions, some of the common options we can use to alter the behavior of dialog, how to use some widgets; among the others: inputbox, checklist, radiolist and yesno. Finally, we will see how to use the data obtained by the widget processing.

In this tutorial you will learn:

  • How to install the dialog utility on Linux
  • What are the most relevant dialog options
  • How to use the inputbox, checklist, radiolist, passwordbox, msbox, calendar and yesno widgets
  • How to manage data derived from the widget processing

Read more

Check Java Version

Check Java Version

There are several ways on how to check what version of Java is installed on your system. Most likely the simplest way is to directly use the java binary in combination with the -version option. To do so run java -version on your terminal.

$ java -version

Read more

How to create a selection menu using the select statement in Bash shell

How to create a selection menu using the select statement in Bash shell

We all very often use bash scripts to automatize boring and repetitive tasks. Sometimes in our scripts we need to ask
the user to perform one or more choices interactively: in this tutorial we will see how to use the Bash shell select statement to perform such operation in very few lines of code.

In this tutorial you will learn:

  • How to use the Bash select statement
  • How to customize the select menu prompt

Read more

script-context-menu-entry

How to extend the GNOME Nautilus file manager with custom scripts

Although GNOME, in its 3.x iteration has been the object of many debates, due to its non-traditional desktop paradigm, it is probably the most used desktop on Linux. The default file manager included in GNOME is Nautilus (the application new name is “Files”). In this tutorial we will see how we can extend the file manager with functionalities provided by custom scripts.

In this tutorial you will learn:

  • How to use custom scripts to extend Nautilus functionalities

Read more

python-logo

How to create and manipulate tar archives using Python

On Linux and other Unix-like operating systems, tar is undoubtedly one of the most used archiving utilities; it let us create archives, often called “tarballs”, we can use for source code distribution or backup purposes. In this tutorial we will see how to read, create and modify tar archives with python, using the tarfile module.

In this tutorial you will learn:

  • The modes in which a tar archive can be opened using the tarfile module
  • What are the TarInfo and TarFile classes and what they represent
  • How to list the content of a tar archive
  • How to extract the content of a tar archive
  • How to add files to a tar archive

Read more

Results of running the application

How to persist data to PostgreSQL in Java

Java is perhaps the most widely used programming language nowadays. It’s robustness and platform-independent nature enables Java based applications to run on mostly anything. As is the case with any application, we need to store our data in some sort of reliable way – this need called databases to life.

In Java database connections are implemented by JDBC (Java Database Connectivity API), that let’s the programmer handle different kind of databases in almost the same way, which makes our lives much easier when we need to save or read data from a database.

In this tutorial we will create an example Java application that will be able to connect to a PostgreSQL database instance, and write data into it. To check that our data insertion is successful, we’ll also implement reading back and print the table we inserted data into.

In this tutorial you will learn:

  • How to setup the database for the application
  • How to import PostgreSQL JDBC Driver into your project
  • How to insert data into the database
  • How to run a simple query to read a database table’s content
  • How to print fetched data

Read more

firefox-logo

How to install Firefox Developer Edition on Linux

The “developer edition” is a special version of the Mozilla Firefox web browser tailored for web developers. It has features stabilized in nightly builds, provides experimental developer tools, and it is configured for development, so some options as remote debugging, are enabled by default.

The browser creates and uses a separate profile, so it can be used together with the standard edition of Firefox (on Linux, profiles are created inside the ~/.mozilla directory).

In this tutorial we will see how to install Firefox Developer Edition on Linux, how to add the application to our PATH, and how to create a desktop launcher for it: the instructions can be applied to any Linux distribution.

In this tutorial you will learn:

  • How to download and install Firefox developer edition
  • How to add the Firefox binary to PATH
  • How to create a launcher for the application

Read more