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Windows socket registry entries required for network connectivity are missing

This tutorial will show how to solve the “Windows socket registry entries required for network connectivity are missing” error.

The Problem

I ran into this error for the time whilst using one of my Windows 10 machines. That said, this solution is certain to work in Windows 10 environments, but it is possible to work in future releases with a similar architecture.

The first thing I noticed was an alert over my Windows’ task bar connection icon. After that, I was unable to access any website like I had no internet connection at all:

Windows 10 task bar connection

Then, I tried the Windows’ network diagnostic tool in order to solve this issue, which printed the following report:

Windows sockets registry entries required for network connectivity are missing message
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EJB: Application Exception vs System Exception

There are two types of exceptions in EJB: application exception and system exception. This guide will show how to identify and implement both of them.

Why two types of exceptions in EJB?

In EJB, it’s important to know whether an exception has occurred because of a business problem or a system error. That way, EJB exceptions are split in two to represent a maybe recoverable business problem (like an ordinary checked exception in Java) or a unexpected and unrecoverable issue caused by a system error or bad coding (like common runtime exceptions).

After all the concepts involved, they are just ordinary exceptions with meaningful metadata defined by annotations or XML configuration in the deployment descriptor to tell the EJB container how to deal with them.

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Java Objects

Java Objects logo

The Java Objects class is a utility class introduced in Java 7 and expanded in Java 8 to provide a collection of static methods to help operating on Java objects. It has null-safe and null-tolerant methods for computing the hash code of an object, returning a string for an object, comparing two objects, null checking and more.

According to Brian Goetz (Oracle’s architect for the Java language), its features are also being introduced into the core of the language, so there is a chance the Objects class becomes more popular in the years that are coming.

That said, we are about to explore how to work with the Objects class.

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Singleton Design Pattern Logo

Singleton is a creational design pattern which ensures that a class has only one instance and provides a global point to access it.


Sometimes it makes sense in a system to have just only one instance of a certain class, e.g. configuration classes that read properties from a unique file or hardware access to send files to a printer.

Although Singleton seems to be one of the most popular patterns and yet, one of the easiest to implement, there are still certain features of the Java language like concurrency and serialisation, that may create some pitfalls in the pattern implementation, pitfalls we have to cover in order to rest assured that our Singleton instances are really singular.

That said, this post is not going to be “just yet another Singleton quick tutorial”, it is going to show how to safely write a piece of code that properly adheres to the pattern’s contract, both using a regular Java class and an alternative implementation using an enum.

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Open SSH connection on Linux

shell to open ssh connection on linux

This tutorial will show you how to open SSH connection on Linux directly on the console, so you don’t need to rely on third party software like Putty.

I’ve seen quite a few people relying on a Putty installation on Ubuntu and/or CentOS to access a remote server through SSH, but despite how good I think Putty is, its usage is far from necessary when you are on a Linux environment.

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