# Java and Java Programming Models. Open Source Microservices Frameworks - [Java](#java) - [Existing Java Implementations](#existing-java-implementations) - [Use Java 11](#use-java-11) - [Java Collections Interview Questions](#java-collections-interview-questions) - [Java Programming Models (Frameworks)](#java-programming-models-frameworks) - [Jakarta EE](#jakarta-ee) - [Eclipse MicroProfile](#eclipse-microprofile) - [Server Vendors providing MicroProfile runtimes](#server-vendors-providing-microprofile-runtimes) - [Spring](#spring) - [SpringBoot](#springboot) - [SpringBoot with Docker](#springboot-with-docker) - [Spring Cloud](#spring-cloud) - [Spring Cloud Kubernetes](#spring-cloud-kubernetes) - [Spring Cloud Config and Spring Cloud Config Server](#spring-cloud-config-and-spring-cloud-config-server) - [Secure Secrets with Spring Cloud Vault and alternatives](#secure-secrets-with-spring-cloud-vault-and-alternatives) - [Quarkus](#quarkus) - [Thorntail (aka WildFly Swarm)](#thorntail-aka-wildfly-swarm) - [Spring Boot VS MicroProfile](#spring-boot-vs-microprofile) ## Java * [reddit.com/r/java](https://www.reddit.com/r/java) * [medium.com/@javachampions : Java is still free](https://medium.com/@javachampions/java-is-still-free-2-0-0-6b9aa8d6d244) * [Oracle Java 11 and OpenJDK](https://blog.joda.org/2018/09/do-not-fall-into-oracles-java-11-trap.html) * [developers.redhat.com: The future of Java and OpenJDK updates without Oracle support](https://developers.redhat.com/blog/2018/09/24/the-future-of-java-and-openjdk-updates-without-oracle-support/) * [redhat.com: The history and future of OpenJDK](https://www.redhat.com/en/blog/history-and-future-openjdk) * [javarevisited.blogspot.com: The 2020 Java Developer RoadMap 🌟](https://javarevisited.blogspot.com/2019/10/the-java-developer-roadmap.html) * [marcobehler.com: Java Versions and Features 🌟](https://www.marcobehler.com/guides/a-guide-to-java-versions-and-features) * [advancedweb.hu: A categorized list of all Java and JVM features since JDK 8 to 14](https://advancedweb.hu/a-categorized-list-of-all-java-and-jvm-features-since-jdk-8-to-14/) * [JDK 15: The new features in Java 15](https://www.infoworld.com/article/3534133/jdk-15-the-new-features-in-java-15.html) Just-arrived update to standard Java features text blocks, hidden classes, the Z Garbage Collector, and previews of pattern matching and records. * [GitHub Welcomes the OpenJDK Project!](https://github.blog/2020-09-30-github-welcomes-the-openjdk-project/) * [advancedweb.hu: A categorized list of all Java and JVM features since JDK 8 to 16](https://advancedweb.hu/a-categorized-list-of-all-java-and-jvm-features-since-jdk-8-to-16/) ### Existing Java Implementations - [Oracle Java](https://www.oracle.com/technetwork/java/javase/overview/index.html) - [Oracle OpenJDK](https://jdk.java.net/11/) - [IBM JDK](https://developer.ibm.com/javasdk/) (based on [Eclipse OpenJ9](https://www.eclipse.org/openj9/)) - [Red Hat OpenJDK](https://developers.redhat.com/products/openjdk/download) - [AdoptOpenJDk](https://adoptopenjdk.net/) (based on [Eclipse OpenJ9](https://www.eclipse.org/openj9/)) ### Use Java 11 - [It’s time! Migrating to Java 11 🌟](https://medium.com/criciumadev/its-time-migrating-to-java-11-5eb3868354f9) - [Oracle's Java 11 trap - Use OpenJDK instead! 🌟](https://blog.joda.org/2018/09/do-not-fall-into-oracles-java-11-trap.html) - [**AdoptOpenJDK 11** Is the New Default 🌟](https://blog.adoptopenjdk.net/2020/06/adoptopenjdk-11-new-default/) - [All You Need To Know For Migrating To Java 11](https://blog.codefx.org/java/java-11-migration-guide/) ### Java Collections Interview Questions * [50+ Java Collections Interview Questions for Beginners and Experienced Programmers](https://medium.com/javarevisited/50-java-collections-interview-questions-for-beginners-and-experienced-programmers-4d2c224cc5ab) ## Java Programming Models (Frameworks) - [Best Java Frameworks Solutions](https://www.itcentralstation.com/categories/java-frameworks) The best Java Frameworks vendors are **Apache Spark**, **Spring Boot**, **Oracle Application Development Framework (Oracle ADF)**, **Jakarta EE**, and **Open Liberty**. Apache is the top solution according to IT Central Station reviews and rankings. One reviewer writes: "Fast performance and has an easy initial setup", and another reviewer writes: "Easy to use and is capable of processing large amounts of data". The 2nd best product is Spring Boot. A user writes: "Very smooth implementation; excellent features for monitoring and tracking network calls ", and another reviewer writes: "Makes it difficult to support a specific functionality in a user-friendly manner, but simplifies application deployment". - **Open Source Microservices Frameworks** (frameworks for microservices development): - [Spring](https://spring.io/projects/spring-boot) - [MicroProfile](https://microprofile.io) Java Programming Model|Technology|Cloud Native (microservices)|Platform :----|:---|:---|:--- [Java EE](https://en.wikipedia.org/wiki/Java_Platform,_Enterprise_Edition)
[Java EE at a Glance](https://www.oracle.com/java/technologies/java-ee-glance.html)|Frontend + Backend
Java EE Monoliths|No|Java EE Middleware Servers (WAS, WebLogic, JBoss EAP, etc) [Jakarta EE (Java EE renamed)](https://jakarta.ee/)|Frontend + Backend|Yes|OpenShift, Kubernetes, etc [MicroProfile](https://microprofile.io/)|Backend (RESTful)|Yes|OpenShift, Kubernetes, etc [SpringBoot (Spring)](https://spring.io/projects/spring-boot)|Backend (RESTful)|Yes|OpenShift, Kubernetes, etc [Spring Cloud (Spring)](https://spring.io/projects/spring-cloud)|Backend (RESTful)|Yes|OpenShift, Kubernetes, etc [Quarkus](https://quarkus.io/)|Backend (RESTful)|Yes|OpenShift, Kubernetes, etc [Thorntail](https://thorntail.io/)|Backend (RESTful)|Yes|OpenShift, Kubernetes, etc etc||| ## Jakarta EE - [developers.redhat.com: Jakarta EE 8: The new era of Java EE explained](https://developers.redhat.com/blog/2019/09/12/jakarta-ee-8-the-new-era-of-java-ee-explained/) ## Eclipse MicroProfile - [Eclipse MicroProfile Project](https://projects.eclipse.org/projects/technology.microprofile) The Eclipse MicroProfile project is aimed at optimizing Enterprise Java for the microservices architecture. - Many innovative "microservice" Enterprise Java environments and frameworks already exist in the Java ecosystem. These projects are creating new features and capabilities to address microservice architectures -- leveraging both Java EE and non-Java EE technologies. - The goal of the Eclipse MicroProfile project is to iterate and innovate in short cycles to propose new common APIs and functionality, get community approval, release, and repeat. Eventually, the outputs of this project could be submitted to the Eclipse Jakarta EE, JCP, OpenJDK or any relevant standards body. - [MicroProfile.io](https://microprofile.io/) Optimizing Enterprise Java for a Microservices Architecture - [developers.redhat.com: Eclipse MicroProfile for Spring Boot developers](https://developers.redhat.com/blog/2018/11/21/eclipse-microprofile-for-spring-boot-developers/) - [Eclipse MicroProfile: 5 Things You Need to Know 🌟](https://medium.com/@alextheedom/eclipse-microprofile-5-things-you-need-to-know-e7a0bc9a3fb6) - [developers.redhat.com: Develop Eclipse MicroProfile applications on Red Hat JBoss Enterprise Application Platform Expansion Pack 1.0 with Red Hat CodeReady Workspaces](https://developers.redhat.com/blog/2020/07/01/develop-eclipse-microprofile-applications-on-red-hat-jboss-enterprise-application-platform-expansion-pack-1-0-with-red-hat-codeready-workspaces/) - [infoq.com: Virtual Panel: The MicroProfile Influence on Microservices Frameworks](https://www.infoq.com/articles/microprofile-microservices/) ### Server Vendors providing MicroProfile runtimes - [WebSphere Liberty from IBM](https://developer.ibm.com/wasdev/websphere-liberty/) - [TomEE from Tomitribe](http://tomee.apache.org/) - [Payara](https://www.payara.fish/) - [RedHat’s WildFly Swarm](http://wildfly-swarm.io/) - [KumuluzEE](https://ee.kumuluz.com/) ## Spring - [Spring](https://spring.io/) - [Spring Framework Architecture 🌟](https://www.javacodegeeks.com/2019/02/spring-framework-architecture.html) - [javatutorial.net: Introduction to Spring Web Framework](https://javatutorial.net/introduction-to-spring-web-framework) - [javarevisited.blogspot.com: 10 JdbcTemplate Examples in Spring Framework](https://javarevisited.blogspot.com/2020/05/10-jdbctemplate-examples-in-spring.html) - [medium.com: Top 10 Courses to Learn Microservices in Java and Spring Framework](https://medium.com/javarevisited/top-5-courses-to-learn-microservices-in-java-and-spring-framework-e9fed1ba804d) - [dzone: How to Create Microservices Using Spring 🌟](https://dzone.com/articles/how-to-create-microservices-using-spring) Let’s consider the use case of BookMyHotel Web Application, developed by a company known as MyInternetSolutions. ### SpringBoot - [SpringBoot](https://spring.io/projects/spring-boot) - [dzone: All About Spring Boot (Tutorials and Articles)](https://dzone.com/articles/spring-boot-framework-tutorials) - [jaxenter.com: CI/CD for Spring Boot Microservices: Part 1](https://jaxenter.com/cicd-microservices-docker-162408.html) - [jaxenter.com: CI/CD for Spring Boot Microservices: Part 2. Extending CI/CD: Kubernetes Continuous Deployment for Microservices](https://jaxenter.com/kubernetes-microservices-162690.html) - [dzone: Deploying Spring Boot App to JBoss Wildfly](https://dzone.com/articles/deploying-spring-boot-app-to-jboss-wildfly) - [Spring Boot: ΒΏwar o jar? Ambos](https://www.adictosaltrabajo.com/2018/12/13/spring-boot-war-o-jar-ambos/) - [javatutorial.net: Spring vs. Java EE](https://javatutorial.net/spring-vs-java-ee) - [medium.com: Spring Cloud kubernetes for hybrid microservices architecture](https://medium.com/javarevisited/spring-cloud-kubernetes-for-hybrid-microservices-architecture-f487d67328d0) - [10 Free Spring Boot Courses and Tutorials for Java Developers](https://medium.com/javarevisited/10-free-spring-boot-tutorials-and-courses-for-java-developers-53dfe084587e) - [**Spring Boot Istio library**: Spring Boot library for integration with Istio](https://piotrminkowski.com/2020/06/10/spring-boot-library-for-integration-with-istio/) * [Spring Boot native images. The path towards Spring Boot native applications](https://spring.io/blog/2020/06/10/the-path-towards-spring-boot-native-applications) * [piotrminkowski.com: Best practices for microservices on kubernetes 🌟](https://piotrminkowski.com/2020/03/10/best-practices-for-microservices-on-kubernetes/) * [piotrminkowski.com: Spring Boot Autoscaling on kubernetes 🌟](https://piotrminkowski.com/2020/11/05/spring-boot-autoscaling-on-kubernetes/) * [spring.io: What's new in Spring Boot 2.4 🌟](https://spring.io/blog/2021/01/17/what-s-new-in-spring-boot-2-4) * [Changes to Application properties/yaml](https://youtu.be/lgyO9C9zdrg?t=1489s) * [arnoldgalovics.com: Java and Spring Boot multiline log support for Fluentd (EFK stack)](https://arnoldgalovics.com/java-and-spring-boot-multiline-log-support-for-fluentd-efk-stack/) * [developers.redhat.com: Spring Boot on Quarkus: Magic or madness?](https://developers.redhat.com/blog/2021/02/09/spring-boot-on-quarkus-magic-or-madness/) #### SpringBoot with Docker * [spring.io: spring boot with docker](https://spring.io/guides/gs/spring-boot-docker/) * [spring.io: Creating Docker images with Spring Boot 2.3.0.M1](https://spring.io/blog/2020/01/27/creating-docker-images-with-spring-boot-2-3-0-m1) * [learnk8s.io: Developing and deploying Spring Boot microservices on Kubernetes](https://learnk8s.io/spring-boot-kubernetes-guide) * [youtube: Creating Docker Images With Spring Boot](https://www.youtube.com/watch?v=1w1Jv9qssqg) #### Spring Cloud - [Spring Cloud](https://spring.io/projects/spring-cloud) ##### Spring Cloud Kubernetes - [github: Spring Cloud Kubernetes 🌟](https://github.com/spring-cloud/spring-cloud-kubernetes) - [Spring Cloud Kubernetes for hybrid microservices architecture](https://medium.com/javarevisited/spring-cloud-kubernetes-for-hybrid-microservices-architecture-f487d67328d0) - [piotrminkowski.com: Microservices with spring cloud kubernetes](https://piotrminkowski.com/2019/12/20/microservices-with-spring-cloud-kubernetes) ##### Spring Cloud Config and Spring Cloud Config Server - [Spring Cloud Config](https://cloud.spring.io/spring-cloud-config/reference/html/) - [Spring Cloud Config Server: Git Backend](https://cloud.spring.io/spring-cloud-config/reference/html/#_git_backend) - [developer.okta.com: Spring Cloud Config for Shared Microservice Configuration](https://developer.okta.com/blog/2020/12/07/spring-cloud-config) - [redhat.com: Spring Boot Microservices on Red Hat OpenShift Container Platform 3 - Software Stack - Externalized Configuration](https://access.redhat.com/documentation/en-us/reference_architectures/2017/html-single/spring_boot_microservices_on_red_hat_openshift_container_platform_3/index#spring_cloud_config) [Spring Cloud Config](https://cloud.spring.io/spring-cloud-config/spring-cloud-config.html) provides server and client-side support for externalized configuration in a distributed system. With the Config Server you have a central place to manage external properties for applications across all environments. ##### Secure Secrets with Spring Cloud Vault and alternatives - [cloud.spring.io: Spring Cloud Vault 🌟](https://cloud.spring.io/spring-cloud-vault/reference/html/) - [developer.okta.com: Secure Secrets With Spring Cloud Config and Vault 🌟](https://developer.okta.com/blog/2020/05/04/spring-vault) Nowadays it is widely recommended to never store secret values in code. Therefore, this tutorial will demonstrate the following alternatives: - Using environment variables for Spring Boot secrets - Secrets encryption with Spring Cloud Config - Secrets management with HashiCorp’s Vault - Using Spring Cloud Vault
[![microservice arch](images/microservice_arch.png)](https://medium.com/javarevisited/10-free-spring-boot-tutorials-and-courses-for-java-developers-53dfe084587e)
## Quarkus - [quarkus.io](https://quarkus.io/) Quarkus is a Kubernetes-native Java stack that is crafted from best-of-breed Java libraries and standards, and tailored for containers and cloud deployments - [Quarkus Images](https://github.com/quarkusio/quarkus-images) This repository contains the container images used by Quarkus. - [quarkus.io: Quarkus for Spring Developers](https://quarkus.io/blog/quarkus-for-spring-developers/) - [redhat.com: Red Hat drives future of Java with cloud-native, container-first Quarkus](https://www.redhat.com/en/blog/red-hat-drives-future-java-cloud-native-container-first-quarkus) - [developers.redhat.com: Quarkus: A quick-start guide to the Kubernetes-native Java stack](https://developers.redhat.com/articles/quarkus-quick-start-guide-kubernetes-native-java-stack/) - [quarkus.io: Quarkus support in IDE's](https://quarkus.io/blog/march-of-ides/) - [dzone: quarkus refcard](https://dzone.com/refcardz/quarkus-1) - [dzone: Build a Java REST API With Quarkus](https://dzone.com/articles/build-a-java-rest-api-with-quarkus) - [developers.redhat.com: Autowire MicroProfile into Spring with Quarkus](https://developers.redhat.com/blog/2019/10/02/autowire-microprofile-into-spring-with-quarkus/) - [dmcommunity.org: Who will win? Spring Boot or Quarkus](https://dmcommunity.org/2020/01/12/who-will-win-spring-boot-or-quarkus/) - [dzone.com: Microservices: Quarkus vs. Spring Boot](https://dzone.com/articles/microservices-quarkus-vs-spring-boot) In the era of containers (the "Docker Age") Java still keeps alive, being struggling for it or not. Who will win: Spring Boot or Quarkus. - [developers.redhat.com: How Quarkus brings imperative and reactive programming together](https://developers.redhat.com/blog/2019/11/18/how-quarkus-brings-imperative-and-reactive-programming-together/) - [developers.redhat.com: Migrating a Spring Boot microservices application to Quarkus](https://developers.redhat.com/blog/2020/04/10/migrating-a-spring-boot-microservices-application-to-quarkus/) - [Quarkus, a Kubernetes-native Java runtime, now fully supported by Red Hat](https://developers.redhat.com/blog/2020/05/28/quarkus-a-kubernetes-native-java-runtime-now-fully-supported-by-red-hat/) - [The road to Quarkus GA: Completing the first supported Kubernetes-native Java stack](https://developers.redhat.com/blog/2020/06/04/the-road-to-quarkus-ga-completing-the-first-supported-kubernetes-native-java-stack/) - [containerjournal.com: Red Hat Adds Java Runtime for Kubernetes to Subscription](https://containerjournal.com/topics/container-ecosystems/red-hat-adds-java-runtime-for-kubernetes-to-subscription/) Quarkus provides access to a library of more than 200 extensions, including tools such as RESTEasy, Hibernate and Eclipse MicroProfile, along with specific extensions fo Red Hat cloud services such as Red Hat AMQ Streams, Red Hat AMQ Broker and Red Hat Fuse. - [developers.redhat.com: Quarkus and Jakarta EE: Together, or not?](https://developers.redhat.com/blog/2020/09/11/quarkus-and-jakarta-ee-together-or-not) - [youtube: CyberJUG-HH:Why is everybody talking about Quarkus?](https://www.youtube.com/watch?v=nXXPOS8gjtA) In this (Why is everybody talking about Quarkus?) Java User Group Hamburg (CyberJUG-HH) session I highlighted possible reasons for Quarkus' popularity, explained Quarkus' optimisation tricks, the differences between Jakarta EE / J2EE / Java EE application servers and Quarkus, discussed the role of MicroProfile and Jakarta EE, migrated a Java EE application to Quarkus, performed multiple deployments, decompiled some code, measured memory consumption and finally cross compiled the Java service to native code using GraalVM. - [developers.redhat.com: Build an API using Quarkus from the ground up 🌟](https://developers.redhat.com/blog/2021/05/11/building-an-api-using-quarkus-from-the-ground-up/) ## Thorntail (aka WildFly Swarm) - [Red Hat Thorntail](https://thorntail.io/) is a framework based on the popular [WildFly Java application server](https://wildfly.org/) to enable the creation of small, stand-alone microservice-based applications. Thorntail is capable of producing so-called just enough app-server to support each component of your system. ## Spring Boot VS MicroProfile - [Dzone: Programming Styles Compared: Spring Framework vis-a-vis Eclipse MicroProfile 🌟🌟](https://dzone.com/articles/programming-styles-spring-boot-vis-a-vis-with-ecli) - [ibm.com: Java Microservices with MicroProfile – RESTful APIs and Dependency Injection. For microservices-based Java apps, knowing how to create REST APIs is an essential skill. Eclipse MicroProfile makes it easier](https://www.ibm.com/cloud/blog/migrate-java-microservices-from-spring-to-microprofile-p2) Spring Boot or MicroProfile for Java microservices apps? Choose the path of least resistance. The Spring Boot and MicroProfile frameworks have many of the same goals (i.e., you can do everything in MicroProfile that you can do in Spring Boot). Both of them are built on top of the same core APIs; even though there are differences in some of the APIs, the work they do is similar.