2020-12-13 13:15
Spring Boot supports the following embedded servlet containers: Tomcat Jetty Undertow You can use Maven, Gradle, or Ant/Ivy as build tools to generate the jar file. However, you may need to… Read More
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2020-12-12 13:15
It’s perhaps difficult to remember life before smartphones. Today, mobile phones have transformed dramatically to become the information and communication hub fundamental to modern lif… Read More
2020-12-11 08:00
Jakarta EE 9 is out, and with it the namespace change from javax.* to jakarta.*. When we talk about the namespace change, we mostly talk about changing the import statements in your code whe… Read More
2020-12-11 05:00
AWS DynamoDB is described as a NoSQL key-value and a document database. In my work I mostly use the key-value behavior of the database but rarely use the document database features, however… Read More
2020-12-10 08:00
Steve, a software development manager, thought John was a “10x” developer. He explained that John could: Coded faster than anyone else.Write and release full applications over a… Read More
2020-12-10 05:00
This is the third part of the article series: Processing real-time data with Storm, Kafka, and ElasticSearch. 1. Introduction In the second part, we learned how to perform searches in Elasti… Read More
2020-12-09 08:00
Hello in this tutorial, we will understand errors and built-in exceptions in python programming. 1. Introduction 1.1 Error A typing mistake can lead to a fault in the programming language be… Read More
2020-12-09 05:00
A parameterized test allows you to run a test against a varying set of data. If you find yourself calling the same test but with different inputs, over and over again, a parameterized test w… Read More
2020-12-08 08:00
Within an enterprise, there are services (systems really) which are widely popular, offer just what you need and are easy to use. There are also systems, which for years the organization tri… Read More
2020-12-08 05:00
Hello in this tutorial, we will understand the round() method to round the numbers while working with decimal numbers in python programming. 1. Introduction The round() method in python is u… Read More
2020-12-07 07:00
Learn 14 Languages & Access More Than 10,000 Hours of High-Quality Language Education Online Hey fellow geeks, This week, on our JCG Deals store, we have another extreme offer.We are off… Read More
2020-12-07 06:10
Helping You Find Your Way with Geocode’s API The Company Behind Geocodeapi SaaS Industries back Geocodeapi. SaaS Industries is an Austrian tech company that develops and supports APIs… Read More
2020-12-07 05:00
1. Introduction Over the last couple of years we have witnessed the astonishing pace and scale of the innovations in the JVM ecosystem. Not only the new JDK release is coming out every 6 mon… Read More
2020-12-06 13:15
ThreadLocal in Java is another way to achieve thread-safety apart from writing immutable classes. If you have been writing multi-threaded or concurrent code in Java then you must be familiar… Read More
2020-12-05 13:15
If you are seasoned Java developer who practices test-driven development (hopefully, everyone does it), it is very likely JUnit 4 has been your one-stop-shop testing toolbox. Personally, I t… Read More
2020-12-04 08:00
Whither Extension Methods? Apparently, there’s a java dialect called XTend which does this, but there’s no obvious equivalent of extension methods in Java. An extension method, a… Read More
2020-12-04 05:00
I’m in the process of reworking an open-source library to make it operate more easily for my use cases. The writer of the library has a particular view of how software should be, and i… Read More
2020-12-03 14:00
Following recent discussion online, I’d like to make what I consider to be an important statement about code. The purpose of code is to express the logic of the software both to the co… Read More
2020-12-03 05:00
As we know, locks are generally used to monitor and control access to shared resources by multiple threads at the same time. They basically protect data integrity and atomicity in concurrent… Read More
2020-12-02 08:00
In my last post, I described the day period support added with JDK 16 Early Access Build 25. That same build also added methods for checking indexes and ranges of long values, which is the s… Read More
2020-12-02 05:00
Every now and then I jump on classes with multiple constructors or classes that are rigorous to work with. Let alone not being able to mock part of their components and at the end being forc… Read More
2020-12-01 20:00
Spring MVC is a web framework based on the model–view–controller pattern. It is based on the Spring principles and supports a wide range of server-side rendering technologies as… Read More
2020-11-30 08:00
Kickstart Your Career as a Data Analyst with 90 Hours of Basic to Advanced Content on Microsoft Excel, Power BI, Tableau, VBA, Python & More! Hey fellow geeks, This week, on our JCG Deal… Read More
2020-11-30 07:00
Perfect for Aspiring Product Managers & Engineers, This Course Bundle Provides 7 Hours of Content on the Game-Changing AI and Machine Learning Tech Hey fellow geeks, This week, on our JC… Read More
2020-11-30 05:00
In 1974, Liskov and Zilles defined a strongly-typed language as one in which “whenever an object is passed from a calling function to a called function, its type must be compatible wit… Read More
2020-11-29 13:15
Bean Validation is the Java standard for validation and can be used in Kotlin as well. However, there are also two popular alternative libraries for validation available in Kotlin: Konform a… Read More
2020-11-28 13:15
JDK 16 Early Access Build 25 (2020/11/18) includes changes for JDK-8247781 (“Day periods support”). As stated in the JDK 16 Early Access Build 25 Release Notes (“Day period… Read More
2020-11-27 08:00
This post shows how to test for expected exceptions using JUnit 5. If you’re still on JUnit 4, please check out my previous post. Let’s start with the following class that we wis… Read More
2020-11-27 07:00
Amp Up Your Programming Skill Set with 270+ Hours of Content on the Leading Coding Languages — Taught by Top-Rated Instructors Ft. Rob Percival, Nick Walter, & More! Hey fellow gee… Read More
2020-11-27 05:00
Previously we used Hoverfly among its state feature. So far our examples have been close to an absolute request match, thus on this blog we will focus on utilising the matchers. Having a goo… Read More
2020-11-26 08:00
Previously we created successfully a Zookeeper ensemble, now it’s time to add some Kafka brokers that will connect to the ensemble and we shall execute some commands. We will pick up f… Read More
2020-11-26 05:00
Main points: DataWeave 2.0 provides mapping capabilitiesJava and DataWeave can achieve the same mappingsDataWeave mapping operator is less verbose than Java DataWeave map operator The DataWe… Read More
2020-11-25 14:00
Design patterns are solutions to known problems. The pattern represents an abstracted solution to a commonly experienced problem. As the solution is abstracted it is language agnostic. A non… Read More
2020-11-25 05:00
It has been a while but as per a friend requested I am going to show you how to deploy a Quarkus microservice behind an Nginx reverse proxy using docker. What are we going to do… I am… Read More
2020-11-24 08:00
A Proof of Concept in Automation testing deserves a thorough preparation and implementation to verify the automation venture. Once it is done right, the QA team can leverage valuable insight… Read More
2020-11-24 05:00
Introduction Code generation is a common thing in modern frameworks. There may be different reasons behind introducing code generation – from getting rid of boilerplate code to reflect… Read More
2020-11-23 06:00
Upgrade Your Programming & Web Development Skills with 38 Hours of Content on Python, Artificial Intelligence, Keras, PyTorch, and More Hey fellow geeks, This week, on our JCG Deals stor… Read More
2020-11-23 05:00
Security questions still exist. They are less dominant now, but we haven’t yet condemned them as an industry hard enough so that they stop being added to authentication flows. But they… Read More
2020-11-22 13:15
Previously we spun up Zookeeper and Kafka locally but also through Docker. What comes next is spinning up more than just one Kafka and Zookeeper node and create a 3 node cluster. To achieve… Read More
2020-11-21 13:15
Hello in this tutorial, we will understand the string replace() method in python programming. 1. Introduction replace() method in python programming returns a copy of a string where all occu… Read More
2020-11-20 05:00
When building a RESTful API we often want to give consumers the option to order collections in a specific way (e.g. ordering users by last name). If our API supports pagination this can be q… Read More
2020-11-19 08:00
JetBrains MPS is our tool of choice to build Domain Specific Languages targeting professionals who are not developers. MPS is a great choice but over several projects we ran into specific is… Read More
2020-11-19 05:00
This is a little bit of experimentation that I did recently to figure out a reasonable code to get all possible permutations of a set of characters. So say given a set of charact… Read More
2020-11-18 08:00
Last month Ben Brumm asked me for the one advice I’d like to give to developers that are working with databases (in reality – almost all of us). He published mine as well as many… Read More
2020-11-18 05:00
I have previously blogged about the optimziations we are doing in the Apache Camel core. The first 3 blogs (part1, part2, part3) were a while back leading up to the 3.4 LTS release. Now we h… Read More
2020-11-17 08:00
In this blog post we are going to look at the new styling and other new options available in OpenAPI and SwaggerUI Quarkus (v1.10.0 +). Styling Default style The default style for Swagger UI… Read More
2020-11-17 05:00
The work with Jakarta MVC 2.0 goes forward. According to the Jakarta EE Specification Process (JESP), we are now in the development phase where we will release as many milestones as we need… Read More
2020-11-16 06:00
Amp Up Your Skills on Electronics, Programming & Robotics with 39 Hours of Content on Raspberry Pi, Python, and ROS2 Hey fellow geeks, This week, on our JCG Deals store, we have another… Read More
2020-11-16 05:00
Hello in this tutorial, we will understand the os.walk method to list the files in a directory using the python programming. 1. Introduction The os.walk(……) method will generat… Read More
2020-11-15 13:15
This is the second part of the article series: Processing real-time data with Storm, Kafka, and ElasticSearch. 1. Introduction In the first part we described the problem and how we are going… Read More
2020-11-14 13:15
Hello in this tutorial, we will explain how a Constructor works in python programming, using examples. 1. Introduction Constructors are used for instantiating an object and assign values to… Read More
2020-11-13 08:00
Kafka popularity increases every day more and more as it takes over the streaming world. It is already provided out of the box on cloud providers like AWS, Azure and IBM Cloud. Eventually fo… Read More
2020-11-13 05:00
Problem Moving from JDK 8 to JDK 11 is quiet subtle. One issue which many people have faced is regarding is GC Logs. Solution JDK 11 uses generic logging mechanism. So flags like PrintGCDeta… Read More
2020-11-12 08:00
Today databases have a lot of functionality that is often not used by software developers because they simply not know that this exists. But knowing about this features can save a lot of tim… Read More
2020-11-12 05:00
A quick and practical guide to calculate the matrix transpose in java. Transpose of a given matrix is nothing but the changing the values and order. 1. Overview In this article, you’ll… Read More
2020-11-11 14:00
A quick example program to create multiplication table in java using simple for loop and while loops. 1. Overview In this article, you’ll learn how to generate and print multiplication… Read More
2020-11-11 05:00
A quick and practical programming guide to selection sort technique in java with along with the algorithm and examples. Selection Sort in java In this tutorial, We will learn aboutanother so… Read More
2020-11-10 08:00
In the IT business, one of the never-ending debate topics is – Agile vs. DevOps. However, both processes are completely different from each other; yet they still have some similarities… Read More
2020-11-10 05:00
Hello in this tutorial, we will understand the different ways to use the map function in python programming. 1. Introduction The map() function in python programming executes a given functio… Read More
2020-11-09 07:00
The Ultimate eLearning Package with 22 Courses on IT Industry-Standard Certifications — CompTIA, SSCP, CFR, CISM, & More Hey fellow geeks, This week, on our JCG Deals store, we hav… Read More
2020-11-08 13:15
Having to make product and technological decisions constantly can become problematic or even overwhelming over time. You may find yourself having to deal with tense situations where your pro… Read More
2020-11-07 13:15
Hello guys, generating PDF files in today’s enterprise applications is quite common. Doing this with Java is not an easy task as Java does not gives default api’s to handle PDF f… Read More
2020-11-06 08:00
This blog post is a follow up on the initial introductory post, Supersonic Subatomic GraphQL, and here we will explore more features, some that is experimental, that we hope to eventually mo… Read More
2020-11-06 05:00
Spring Mock-MVC can be a great way to test Spring Boot REST APIs. Mock-MVC allows us to test Spring-MVC request handling without running a real server. I used Mock-MVC tests in various proje… Read More
2020-11-05 08:00
When building RESTful APIs over HTTP the PUT method is typically used for updating, while POST is used for creating resources. However, create and update operations do not perfectly align wi… Read More
2020-11-05 05:00
One of the definitions of refactoring is to change the structure of the code without changing its behaviour. This requires the existence of unit tests. However… Sometimes we want to b… Read More
2020-11-04 08:00
Android is a kind of os getting popular than many other OS. Most of the smartphone population traffic is used on android. Many top features are used to build with smartphone devices. Applica… Read More
2020-11-04 05:00
Version controlling your RAML RESTful API specifications allows you to continue maintaining previous version of your APIs. The API designer from MuleSoft has a build in version control featu… Read More
2020-11-03 08:00
On the previous blog we focused on spinning up our first Akka project. Now it’s time to add a test for our codebase. First thing to get started is adding the right dependencies to the… Read More
2020-11-03 05:00
Allow an object to alter its behavior when its internal state changes. The object will appear to change its class. Participants Context: defines the interface of interest to clients Maintain… Read More
2020-11-02 07:00
From Platform Basics to AppExchange — Start Your Awesome Admin Journey with 53 Hours of Beginner to Advanced Salesforce Content Hey fellow geeks, This week, on our JCG Deals store, we… Read More
2020-11-02 05:00
Without violating encapsulation, capture and externalize an object’s internal state so that the object can be restored to this state later. Participants Memento: stores internal state… Read More
2020-10-31 13:15
There are occasion when it is more convenient to create an array inline. Here are several way to declare and initialise primitive arrays and java.util.Lists type arrays. Declare a primitive… Read More
2020-10-30 08:00
We have created a new quickstart that extends OptaPlanner use case portfolio with the facility location problem and also demonstrates building a cloud-native application using Quarkus, the n… Read More
2020-10-30 05:00
Encapsulation, as you know, is one of the four key principles in object-oriented programming. Encapsulation, according to Grady Booch et al., is “the process of hiding all the secrets… Read More
2020-10-29 08:00
The world is witnessing the rise of Agile methodologies in software development. They require a new approach to software testing, which must well align with the nature of Agile, a fast-movin… Read More
2020-10-29 05:00
We’ve been hearing all about it. Jakarta EE 9 will be released in November 2020. The Jakarta EE working group and community have been working hard to bring this release to… Read More
2020-10-28 08:00
Akka is a free, open-source toolkit and runtime for building highly concurrent, distributed, and resilient message-driven applications on the JVM. Along with Akka you have akka-streams … Read More
2020-10-28 05:00
In this second part of docker tutorial, I’ll explain basics of networking in docker with stand-alone containers. Remember from the previous part of the tutorial where we mapped port of… Read More
2020-10-27 05:00
Main points: property values can be hidden in Runtime Managerproperty names must be listed in the mule-artifact.xml fileproperty values can be edited manually and will remain maskedvalues re… Read More
2020-10-26 07:58
Whether you’re a developer or not, one thing for sure is that scraping SERPs (Search Engine Results Page) can be a tough nut to crack on Google or any other search engine. The main hol… Read More
2020-10-26 07:00
Over 50 Educational Apps for Your Kids! Grammar, Comprehension, Colors, Animals, Geography, Math, & More Hey fellow geeks, This week, on our JCG Deals store, we have another extreme offe… Read More
2020-10-26 05:00
This article describes how you can use JShell to download and execute a Java application. It will eliminate the need for the installation of the application. Do not install, just run! The fi… Read More
2020-10-25 13:15
In the last two posts, we looked at generic architecture diagrams and security-specific diagrams. These diagrams reflect the current architecture of a system. This time we will look at using… Read More
2020-10-24 12:15
While developing a spring boot application, sometimes we need to run a method or a piece of code at startup. This code can be anything ranging from, logging certain information to setti… Read More
2020-10-23 07:00
Java Virtual Machine (JVM) generates 3 critical artifacts that are useful for optimizing the performance and troubleshooting production problems. Those artifacts are: Garbage collection (GC)… Read More
2020-10-23 04:00
Running a PostgreSQL instance ad-hoc for testing is not always as bootstraping as it should be. This blog will run a PostgreSQL instance that connects to your workstation’s network and… Read More
2020-10-22 13:00
Using AWS CodeBuild, I was using a buildspec that was to run an executable JAR file to execute JUnit tests. Here is my buildspec: 1 version: 0.2 env: secrets-manager: … Read More
2020-10-22 10:00
We know how the code we write works, we understand it, we don’t need comments, it’s obvious, of course, we wrote it. This is what we all think and its true – well today its… Read More
2020-10-21 04:00
This is an article of processing real-time data with Storm, Kafka and ElasticSearch. 1. Introduction How would you process a stream of real or near-real time data? In the era of Big Data, th… Read More
2020-10-20 07:00
Java 15 introduces Sealed Classes, a preview language feature, that allows classes/interfaces to restrict which other classes/interfaces may extend or implement them. Here is an example: 1 2… Read More
2020-10-20 04:00
It happens to all of us. We develop stateless applications that can scale horizontally without any effort.However sometimes cases arise where you need to achieve some type of coordination. Y… Read More
2020-10-19 06:00
Manage Projects, Create Tasks, Track Time, & Get Paid Faster Through Invoices with This All-in-1 Project Management Software Hey fellow geeks, This week, on our JCG Deals store, we have… Read More
2020-10-19 04:00
I have previously blogged about the optimziations we are doing in the Apache Camel core. The first 3 blogs (part1, part2, part3) were a while back leading up to the 3.4 LTS release. Now we h… Read More
2020-10-18 12:15
In this docker tutorial series, my aim is to explain basics of docker and to do that with min number of words but maximum number of examples. Before doing anything I want you to install dock… Read More
2020-10-17 12:15
OpenSSL is an omnipresent tool when it comes to encryption. While in Java we are used to the native Java implementations of cryptographic primitives, most other languages rely on OpenSSL. Ye… Read More
2020-10-16 10:00
Automation Testing Introduction Automation testing has become a recognized domain in the world of software testing. As the name implies, automation testing involves the use of automated tool… Read More
2020-10-16 07:00
A quick and practical guide on how to convert String to String Array in differnet ways in java. 1. Overview In this article, you’ll learn how to convert String to String Array in java… Read More
2020-10-16 04:00
A quick and programming guide to how to get the union of two unsorted arrays in java with example programs. 1. Overview In this article, you’ll learn how to get the union of two arrays… Read More
2020-10-15 16:00
A quick and practical guide to find and to calculate the average of numbers in array using java language. 1. Overview In this article, you’ll learn how to calculate the average of numb… Read More
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