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• JAR file (Java Archive)

  A Java Archive, or JAR file, contains all of the various components that make up a self-contained, executable Java application, deployable Java applet or, most commonly, a Java library to which any Java Runtime Environment can link. Continue Reading

• embedded Tomcat

  An embedded Tomcat server consists of a single Java web application along with a full Tomcat server distribution, packaged together and compressed into a single JAR, WAR or ZIP file. Continue Reading

• CSS (cascading style sheets)

  This definition explains the meaning of cascading style sheets (CSS) and how using them with HTML pages is a user interface (UI) development best practice that complies with the separation of concerns design pattern. Continue Reading

• Hibernate

  Hibernate is an open source object relational mapping (ORM) tool that provides a framework to map object-oriented domain models to relational databases for web applications. Continue Reading

• const

  Const (constant) in programming is a keyword that defines a variable or pointer as unchangeable. Continue Reading

• Definitions to Get Started

  • JAR file (Java Archive)
  • embedded Tomcat
  • CSS (cascading style sheets)
  • Hibernate

  • const
  • inversion of control (IoC)
  • Pascal case
  • Java Mission Control

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• How to build a Spring Boot 12-Factor app

  Here we look at how the Spring Boot framework supports the Twelve-Factor App methodology, and where tools such as GitHub, Docker and Kubernetes fill in the voids.Continue Reading

• Introduction to Docker quiz

  These Docker questions and answers will test your knowledge of the fundamentals of Docker, but it won't be easy. Take this quiz and see if we can stump you.Continue Reading

• inversion of control (IoC)

  Inversion of control, also known as the Hollywood Principle, changes the control flow of an application and allows developers to sidestep some typical configuration hassles.Continue Reading

• Java naming conventions, explained

  You could start a Java variable with a dollar sign, but no one does. When you write Java code, always follow these standard Java naming conventions.Continue Reading

• Why is Java platform-independent?

  Sun Microsystems architects designed Java to be cross-platform. But why? Here we look at not only why Java works across platforms, but also how it achieves its platform independence.Continue Reading

• Learn how to save to local storage in this git stash tutorial

  Sometimes developers need to jump off the main distributed development branch to local storage. Follow this git stash tutorial to learn the ins and outs of this Git command.Continue Reading

• Lessons from Fluentd: How to name a project in the SEO age

  Dreaming of wide-scale adoption for your new project? You'll need the right name. Here's how Fluentd got its name, and what you can learn from its SEO-driven process.Continue Reading

• How technologists should approach professional development

  Old approaches to professional development don't stand up to the pace of change in the cloud-native world. Here's how DevOps professionals can cope.Continue Reading

• Test your knowledge of Java foundations

  Whether you're new to Java or have worked with the language for years, you need to know the foundational building blocks. Review the basics in this Java quiz.Continue Reading

• A guide to common variable naming conventions

  Every developer should know the basic variable naming conventions to more easily move from language to language. Review the common ones here like Pascal, camel and snake case.Continue Reading

• Interpreted vs. compiled languages: What's the difference?

  Learn the difference between compiled languages like Go and interpreted ones like Java. One language is platform agnostic. The other can run a bit faster.Continue Reading

• Incorporate diversity and inclusion in technology design

  DEI in technology is about more than creating a diverse workplace. We talked to a few DEI professionals about how teams build tools with diversity and inclusion in mind.Continue Reading

• How do you become a developer advocate?

  For those who love to code and want to share their IT knowledge, the developer advocate job might be a good fit. Learn how to make the transition from developer to advocate.Continue Reading

• How to run Jenkins builds on Docker

  In this Jenkins and Docker integration tutorial, I’ll show you how to create a Jenkinsfile build with Docker. Just pull a Jenkinsfile from a GitHub repository, and Docker will take care of the rest.Continue Reading

• Pascal case

  Pascal case is a naming convention in which developers start each new word in a variable with an uppercase letter.Continue Reading

• Java garbage collection interview questions and answers

  From stop-the-world events to the impact of JVM pause times, these are the Java garbage collection questions and answers developers need to know before an interview.Continue Reading

• How use Epsilon GC to stop Java garbage collection

  The best way to stop Java garbage collection from happening is to use the experimental Epsilon GC, no-op garbage collector from JDK 11. Learn how and when to use it.Continue Reading

• A tough, 10-question Java garbage collection quiz

  Do you know which Java garbage collector is deprecated and which is best for stateless apps? Test your knowledge in this Java GC algorithm and tuning quiz.Continue Reading

• A better Gitflow diagram with branches, merges and color

  Developers deserve a better Gitflow diagram, so we've given it to them. See the new and improved Gitflow diagram with support and bugfix branches and a bit of color.Continue Reading

• Use this Java performance tuning guide to optimize your JVM

  There are two steps to Java performance tuning. First, assess your system to make sure it can improve. Then, optimize shared resources like CPU and memory.Continue Reading

• 10-question Gitflow version control quiz

  Gitflow version control is a DevOps-friendly way to manage the different branches of code in your environment. Make sure you're up to date on the latest developments and strategies.Continue Reading

• Test your knowledge of JVM profiling tools with this quiz

  Since their inclusion in Java 11, Java Flight Recorder and JDK Mission Control have become the de facto Java profiling tools for the JVM. Test your knowledge with these 10 questions.Continue Reading

• Java Mission Control

  Java Mission Control is a performance-analysis tool that renders sampled JVM metrics in easy-to-understand graphs, tables, histograms, lists and charts.Continue Reading

• Java Flight Recorder

  Java Flight Recorder is a Java Virtual Machine (JVM) profiler that gathers performance metrics without placing a significant load on resources.Continue Reading

• What makes an effective microservices logging strategy?

  System size and scale play a big role in microservices logging. Follow these best practices to develop a solid logging strategy within a microservices architecture.Continue Reading

• How is asynchronous microservices tracing best accomplished?

  How can you trace a tricky workflow in an asynchronous microservices-oriented architecture? Two options include correlation IDs and distributed tracing tools.Continue Reading

• Test your knowledge of variable naming conventions

  What's the difference between snake case and camel case? Or kebab case and pascal case? Try this 10-question variable naming quiz to learn more about programming variables.Continue Reading

• Kebab case

  Kebab case -- or kebab-case -- is a programming variable naming convention where a developer replaces the spaces between words with a dash.Continue Reading

• Full GitHub Actions environment variables list for YAML build workflow scripts

  The GitHub Actions environment variables available to a developer's workflows will vary from Ubuntu to Windows to MacOS. Here's a full environment variables list for each and why developers should ...Continue Reading

• Jenkins GitHub Webhook build trigger example

  Running into difficulty with GitHub Webhooks and Jenkins builds? This Jenkins and GitHub webhook integration example shows how to trigger remote builds without the 403 no valid crumb in request ...Continue Reading

• 10 best GitHub Actions examples

  Here are the 10 best GitHub Actions examples for developers and DevOps admins that want to learn and master continuous integration and deployment.Continue Reading

• How to use GitHub Actions secrets to hide your tokens and passwords

  You can confidently store keys, tokens and passwords with GitHub Actions secrets. This quick, not-so secret tutorial, provides an example of how to do exactly that.Continue Reading

• Quickly find and use a GitHub URL example

  This example shows you how you can find and use the GitHub URL. Clone, fetch, push and pull to your remote repo easily with the GitHub URL at your disposal.Continue Reading

• What are the most essential microservice design principles?

  Don't hinder a microservices architecture because of a faulty design. Keep these five design principles in mind to build the proper components for your microservices architecture.Continue Reading

• An Apache Commons FileUpload example and the HttpClient

  In this article you will have a look at the capabilities of the HttpClient component and also some hands-on examples.Continue Reading

• 10 microservices quiz questions to test your knowledge

  Don't sweat the details with microservices. Take this 10-question quiz to boost your microservices knowledge and impress interviewers during a job hunt.Continue Reading

• Snake case

  Snake case is a naming convention where a developer replaces spaces between words with an underscore.Continue Reading

• How to run a Jenkins WAR file

  Here's a quick example of how to run a Jenkins war file from the command line, DOS prompt or terminal window in Linux/Ubuntu. The short story? java -jar jenkins.warContinue Reading

• Fix the Jenkins "No such DSL method withMaven found" error

  Here's a quick fix to the Jenkins 'No such DSL method 'withMaven' found among steps: NoSuchMethodError' error. Hint? Install the Jenkins Maven pipeline plugin.Continue Reading

• Use Jenkins' Warning plugin for CheckStlye, PMD and FindBugs reports

  The Jenkins Warnings plugin replaces the deprecated CheckStyle, FindBugs and PMD ones. This static code analysis in Jenkins example shows you how to integrate Jenkins, CheckStyle, FindBugs and PMD ...Continue Reading

• How to install Jenkins on Ubuntu 20.04 in 7 simple steps

  Here's a quick example to show you how to install Jenkins on Ubuntu 20. Additionally, we'll install Git and test your Jenkins installation with a Hello World build job.Continue Reading

• A declarative Jenkins pipeline for Ant builds on Docker example

  The easiest way to build your Apache Ant projects in Jenkins is with a pipeline and a Jenkinsfile that takes advantage of an Ant based Docker container. In this Apache Ant, Docker and Jenkins ...Continue Reading

• How to use Jenkins with Ant to build your Java apps

  Here's a simple example of how to build your Java apps in Jenkins with Ant. We demonstrate both the Jenkins Ant plugin and the Jenkins pipeline approach with a Jenkinsfile as well.Continue Reading

• A GitHub Pages tutorial on how to host personal websites

  Follow these steps to set up a GitHub repository, clone the repo and host a personal website on GitHub Pages with contents indexable by Google.Continue Reading

• How can I become an AWS Authorized Instructor?

  To become an AWS Authorized Instructor, you need deep knowledge of Amazon products and services and must be able to communicate this wealth of technical information.Continue Reading

• An example of how to use the git stash command

  Developers must occasionally pivot quickly from one task to another. Git stash is a simple command that lets you temporarily shelve changes and hold your place for when it's time to return to your original task.Continue Reading

• A Java programming career path can open doors beyond code

  A Java programming career path can lead to so much more than code. Programmers should consider these options that extend beyond the confines of software development.Continue Reading

• 3 ways to implement AI in software development

  Further advancements to AI make it a more appealing and useful option for enterprise software development. Here are three ways to implement AI and increase developer productivity.Continue Reading

• Get automated with this RPA and UiPath tutorial for beginners

  Developers can eliminate tedious and monotonous tasks with the help of robotic process automation. This UiPath tutorial highlights the early steps with any RPA platform.Continue Reading

• A HibernateUtil class example to simplify JPA code

  Developers can use HibernateUtil to mitigate access to JPA EntityManager and create more readable, less resource intensive code for data-driven applications.Continue Reading

• An introduction to RPA programming with UiPath Studio

  Follow this UiPath Studio tutorial for the basics of RPA programming and see how developers can improve their skills as they build in-depth applications.Continue Reading

• Use the Struts jQuery plugin to simplify Ajax request cycles

  The Struts 2 Ajax template is deprecated, but the Strut jQuery plugin is a more than capable replacement. In this Struts jQuery tutorial we show you how to integrate Ajax calls into your modern ...Continue Reading

• How to git stash untracked files with a push

  Need to add untracked files and otherwise ignored files into the git stash? Here's how to use the --include-untracked and --all git stash push options.Continue Reading

• WebAssembly Hub boosts Envoy filter development

  Examine WebAssembly Hub's features, why developers have turned to the portal to share Envoy filters and how it seems to be built for the long haul.Continue Reading

• How to scale automation in DevOps environments

  With the right tools and processes, programmers can automate at scale many of today's manual tasks. Here's how one company developed automation-at-scale best practices.Continue Reading

• Struts 2 development with the Eclipse IDE tutorial

  The combination of Apache Struts and Eclipse makes for a powerful development environment. Learn how to integrate the two open source tools and get developing Java web applications quickly.Continue Reading

• The Apache Struts Hello World example

  Here's a simple Struts Hello World example for anyone interested in learning how to use the latest Struts 2.5 release. The Apache Struts Framework has come a long way in the last 20 years.Continue Reading

• Apache Struts 2.5 example with no Struts config XML file

  Learn to develop a modern Java web application with this Apache Struts 2.5 example. No Struts config XML files are required. This zero-config Struts example goes without!Continue Reading

• How JPA EntityManager handles Hibernate transaction management

  Follow this JPA EntityManager persist example tutorial to see how it can be used for transaction management and how to save changes to the database.Continue Reading

• git stash

  Git stash is a built-in command with the distributed version control tool in Git that locally stores all the most recent changes in a workspace and resets the state of the workspace to the prior commit state.Continue Reading

• How to easily merge and resolve git stash pop conflicts

  Don't let a conflict with git stash pop derail development. Here's how to merge and resolve this issue and clean up code for proper programming.Continue Reading

• 3 ways a volunteer programmer can help in a pandemic

  DevOps pros can help local and state agencies battle COVID-19. Here are three ways they can volunteer their time during a pandemic.Continue Reading

• 3 ways to have JPA and Hibernate create tables in a database

  JPA frameworks such as Hibernate can automatically create tables. Here are three ways to have JPA and Hibernate create tables in a database.Continue Reading

• Simple database integration with the JPA persistence.xml file

  The persistence.xml file plays a significant role in all facets of JPA-based application development. Examine the file's properties for a simple configuration to ease development.Continue Reading

• Create a distraction free JPA and Hibernate dev environment

  A minimalistic approach is the way to go for development with Hibernate and JPA. Create a development environment with only the basics -- a JDK, Hibernate and a text editor -- to get started.Continue Reading

• Fix for the GitLab "Unable to locate package gitlab-ee" on Ubuntu 20

  If you're doing a self-hosted GitLab Ubuntu 20 install and you hit the "Unable to locate package gitlab-ee" error, here's the solution to fix the problem.Continue Reading

• 5 tool categories to build a powerful DevOps technology stack

  Want to speed application delivery and deployment? Consider adding one of these five DevOps tools and technologies to your IT department.Continue Reading

• GraalVM

  GraalVM is a tool for developers to write and execute Java code.Continue Reading

• The Git working tree, index and commit history explained by example

  This quick tutorial explains the importance of the Git working tree. With the help of the git status command, you'll become an expert on how the popular DVCS tool transforms the file system.Continue Reading

• How to change the last Git commit message quickly

  How can a developer change the message associated with the last git commit before an update? Use the following tutorial on the amend command to alter the last Git commit message.Continue Reading

• Developing a COVID-19 application? Design it the right way

  Application developers with skills and an idea could design an app to combat the virus. Follow these insights to effectively design and deploy a coronavirus-related app.Continue Reading

• How developers can volunteer during the COVID-19 pandemic

  What resources can developers offer to go against COVID-19? Explore some promising developer volunteer and open source project opportunities to see how you can help.Continue Reading

• How to refactor the God object class antipattern

  Loose coupling can inadvertently create a God object problem in an object-oriented software system. Here's how to get rid of the issue and simplify the design in five easy steps.Continue Reading

• 6 top webpage performance metrics to monitor

  Webpage performance is paramount for digital success. To monitor webpage performance, use these top six metrics.Continue Reading

• How to use the git clone command with GitHub by example

  Move code from remote-hosted version control repositories into local ones with one command. Follow this Git clone tutorial to move code into local environments.Continue Reading

• How to integrate Nexus with Jenkins for simpler builds

  Integrate Nexus with Jenkins in your local environment to simplify development and run build jobs with minimal headaches.Continue Reading

• HTML (Hypertext Markup Language)

  HTML (Hypertext Markup Language) is a text-based approach to describing how content contained within an HTML file is structured.Continue Reading

• How to create a local repository with the git init command

  Follow this git init tutorial to create a local repository, add files to the repository and perform commits on your local machine as you get started with distributed version control.Continue Reading

• How to use the git remote add origin command to push remotely

  Need to connect your local Git repository to a remote one? The git remote add command can make it happen. Developers call on it to push to GitHub and other cloud-based tools.Continue Reading

• Install Eclipse IDE on Ubuntu in 5 easy steps

  Software development is greatly simplified by an IDE, like Eclipse. In this video tutorial, we demonstrate how to install the Eclipse IDE on the Ubuntu distribution of Linux.Continue Reading

• How to use the Jenkins multi-configuration project

  In this Jenkins Matrix project plugin example, create a two-dimensional build job that runs 16 build jobs at once.Continue Reading

• Why the 8 Java primitive data types are not objects

  What's the difference between Java primitive types and objects? To start, don't classify primitive types as objects. Let's explore the 3.5 categories that primitive types fall into.Continue Reading

• A brief history of Java: How it forever changed programming

  The Java programming language is an important tool in an application developer's quiver. But Java has also undergone many changes on the road to becoming the standard it is today.Continue Reading

• How to properly perform Java String comparisons

  Don't let incorrect Java String object comparisons bog down your code. Follow this tutorial to understand the differences between =, == and .equals.Continue Reading

• Simplify a cloud-native, Spring Boot Docker deployment

  How do you deploy a Spring Boot application to Docker? It's not as complicated as you might think. Follow this example to move and test your app within a container.Continue Reading

• JDBC tutorial: Easy installation and setup with Apache Derby

  New database developers can get up to speed with this tutorial on JDBC and Apache Derby. Follow these steps to install and connect to the Derby database on your terminal.Continue Reading

• How to test and deploy WARs with Tomcat and Eclipse

  With the proper configuration and integration, it's easy to deploy WAR files from Eclipse to Tomcat. Follow these five steps that every developer should know.Continue Reading

• A simple Java 8 Predicate lambda interface with examples

  Use this Java Predicate example to help developers learn lambdas, expand functional programming and reduce code verbosity in their environment.Continue Reading

• How to run Java preview features such as JDK 13 text blocks

  Follow these five steps to enable the JDK 13 text blocks as part of the preview features in the latest Java release and use multi-line String literal in your code.Continue Reading

• Ideas on how to hold a successful code hackathon

  Want to host a hackathon? Here are some ideas on what a company can do to host an event that solves problems and reenergizes the organization. Just don't forget the food.Continue Reading

• A Jenkins tutorial for beginners with examples

  If you're ready to try Jenkins, this quick start tutorial lays out the specific steps you'll need to take to download and install the CI tool on your local machine.Continue Reading

• Is Java slow? Compared to C++, it's faster than you think

  If you find that Java is slower than other languages, such as C++, here's how to better compare the two and the major differences between compiled and interpreted languages.Continue Reading

• 5 steps for an easy JDK 13 install on Ubuntu

  Follow these five steps for an easy Java 13 installation on Ubuntu, and don't forget to set JAVA_HOME and the PATH variables.Continue Reading

• Guide to practicing cloud-native development

  In this guide, learn about cloud-native development -- what it is, how vendors try to exploit it and how to bring it to life with the help of a DevOps environment.Continue Reading

• Cloud marketplace as a service creates new dev possibilities

  A neutral cloud marketplace would allow developers to pick and choose applications, without the constraints of one cloud. What could that mean for you?Continue Reading