From frameworks to IDEs to application servers, there’s no shortage of technology for a developer to invest in. Here, we dive into some of the most widely used Java technologies for developers to learn for a competitive edge.Table of Contents:FrameworksPlatformsIDEsApplication ServersBuild ToolsTesting ToolsFor a comprehensive overview of the top Java technologies being used in 2021, download our Java Developer Productivity Report.Download ReportJava FrameworksChoosing a Java framework can be a big undertaking when looking at the sheer number of options. However, certain frameworks are better for specific needs, such as microservices vs modular monoliths or front-end vs back-end. Architects regularly debate what type of environment is best suited for the use case applications are created for. The different frameworks used can make applications run more efficiently and make onboarding new engineers easier. For those beginning their search, start with our guide to the Best Java Frameworks. For developers working exclusively with microservices, we recommend starting with Popular Java Microservices Frameworks. Learn about individual frameworks:What is Spring Boot?Java EE vs SpringSpark Java Web FrameworkSpring vs. the World: Comparing Spring Boot AlternativesPlatformsA platform serves as the base to all other applications. Platforms are often run through the cloud, providing a company the ability to deploy applications remotely. Popular platforms today include Pivotal Cloud Foundry and AWS, both cloud-based. Watch a tutorial on how Cloud Foundry works. PaaS, or platform as a service, is a cloud computing offer in which companies sell a platform and bundle of services. It’s a pay-as-you-go model that allows small businesses and enterprises alike to deliver apps to their customers. Check out the 2021 Java Developer Report to see the top PaaS providers.Some platforms are more focused on building robust e-commerce solutions like Hybris, which is a Java platform commonly used to create e-commerce websites. The major advantage of tools like this is that they have a consistent architecture that is being used by any developer on the platform. SAP Hybris ResourcesWhat Is SAP Hybris? — Start here to learn about this Java platform.How JRebel Accelerates SAP Hybris Development — Over 50% of Hybris developers experience redeploy times over eight minutes. Download our datasheet to learn more.JRebel Hybris Installation — Watch the video below on how to configure JRebel for Hybris.Java IDEsIDEs, or Integrated Development Environments, are tools used by developers to simplify the process of developing applications locally. They combine all the developer tools you need in a singular interface—edit code, compile, build, and debug in one place.According to the 2021 Java Developer Report, the most common IDE developers use is IntelliJ IDEA—a subscription-based IDE from JetBrains. IntelliJ has become quite an effective application at creating minimalistic environments that run efficiently on most developer machines.The second most popular IDE was Eclipse, followed by VSCode and NetBeans. Check out the resources below to learn more about specific IDEs, or read this article for a breakdown of our top three Java IDEs to use in 2022.ShortcutsTutorialCheat SheetJRebel and Multi-module ApplicationsGetting Started Cheat Sheet Shortcuts Cheat SheetNetBeans IDE Updates and Improvements Application ServersApplication servers are needed for applications to successfully run on. Like most of the tools on this page, there are a multitude of servers to choose from. When deciding, research the following factors:PerformanceAdministrationDevelopmentSupportScalabilityReliabilityCostSee a comprehensive guide to application server rankings.In 2021, the most popular application server for Java developers was far and away the open-source Apache Tomcat. Other popular choices include: JBoss/WildFly, WebLogic, Jetty, and GlassFish.Installing an Application ServerFor JRebel customers who would like to configure JRebel and their application server of choice, we have a few tutorial videos. Wildfly Installation VideoBuild ToolsBuild tools allow developers to compile, package, and deploy code. When choosing a build tool, architects should consider how the tool:Adapts to changing product requirementsExpedites build script creationHandles compilation and resource management tasksHandles different profiles (development vs. production)Ranks for ease of use, so developers can quickly onboard Begin here >> Getting Started With Java Build Tools, Top Java Development Tools and SoftwareOnce you know what a build tool is, how they work, and what makes a successful build tool, you can compare build tools. According to past Java Developer Reports, the most common build tools are Gradle and Maven, with Ant being used much less frequently. Read our article comparing the three to learn more.Looking to switch to Maven? Check out our introductory article and our cheat sheet.Already a Gradle user? See how you can make your Gradle builds faster.Testing ToolsDevelopers use testing tools to find bugs in their software before it’s released. Testing tools run the gamut from unit testing to web application testing to performance testing. We’ve rounded up some of the best from each category to help you get started.Best Java Performance Testing Tools and Technologies Top 5 Java ProfilersStatic Code Analysis in Java GuideMock Testing with MockitoSelenide for UI Acceptance TestingSpock Testing Groovy and Java ApplicationsUnit TestingUnit tests perform a small task and then verify that the result is the expected one. Unit testing can be done through a framework, such as JUnit, or a tool, like XRebel. JUnitJUnit is the most widely-used testing framework for Java applications. Read our overview blog to learn about the latest version, JUnit 5. Then check out the JUnit cheat sheet for reference to code snippets and annotations. Other Resources and Java ToolsByte Buddy Command Line ToolsJDK ToolsOpen Source vs Commercial Java Tools Web Application Development ToolsOnce you’ve started developing with your Java tools and technologies, you may find yourself wasting time on redeploys. If you’d like to streamline your development even more, try JRebel. JRebel is another Java tool that can help you save time by skipping redeploys.Start Free Trial