The Java language is initiated by James Gosling, Mike Sheridan and Patrick Naughton is June 1991. After several years, the company Sun Microsystems released the first version of Java. Here its principles:

1. It must be simple, object-oriented, and familiar.
2. It must be robust and secure.
3. It must be architecture-neutral and portable.
4. It must execute with high performance.
5. It must be interpreted, threaded, and dynamic.

Java logo

That is to say:

Java is C++ without the guns, clubs and knives.

James Gosling, one of inventors of Java language

Java is a most famous programming language, it is in the top 10 of the languages the most present on the Internet resources and with the highest number of contributors respectively with the TIOBE index that counts the search engine hits, and the octoverse annual report of Github that counts the number of unique contributors of java projects.

But the mascot of Java is Duke that plays the role of a software agent that performed tasks for the user:

Duke the Java mascot

The best resource about Java is surely the Effective Java book with its different editions:

Learning the art of programming, like most other disciplines,
consists of first learning the rules and then learning when to break them.

Joshua Bloch, author of Effective Java

Effective Java book

But Sun Microsystems had an issue a business model, and Oracle acquired Java in January 2010. Now the project has 2 main versions, an open source version with OpenJDK and commercial version with Oracle JDK. These both Java Development Kit are available respectively at https://openjdk.java.net and https://www.oracle.com/java.

There are several JDK vendors among AdoptOpenJDK, Amazon Correto, SAP, Red Hat, Azul, IBM. The most of the vendors have a project based on OpenJDK. The Java Community Process (JCP) provides a Technology Compatibility Kit (TCK) to certify whether a JDK build meets the Java standards. Once a build passes the TCK, it can be referred to as Java SE compatible. The certification process requires a commercial license from Oracle.

You can see, what is the usage of the Java ecosystem in terms of IDE, Java vendors, Java version, Java with the Snyk company survey, or the Jrebel company survey.

To follow the evolution of the ecosystem, you can subscribe to the Java magazine.

References:

• https://blogs.oracle.com/java-platform-group/the-arrival-of-java-14
• https://dzone.com/articles/an-overview-on-jdk-vendors
• https://blog.overops.com/java-wish-list-the-top-differences-between-java-scala-groovy-clojure-and-kotlin
• https://mreinhold.org/blog/forward-faster
• https://www.jrebel.com/blog/2020-java-technology-report
• https://blogs.oracle.com/java-platform-group/faster-and-easier-use-and-redistribution-of-java-se
• https://www.developpez.com/actu/159181/Oracle-annonce-des-changements-pour-Java-SE-deux-versions-par-an-licence-GPL-des-fonctionnalites-commerciales-du-JDK-d-Oracle-en-open-source
• https://www.developpez.com/actu/185779/Java-8-ne-va-plus-recevoir-de-mises-a-jour-et-correctifs-de-securite-a-partir-de-septembre-a-moins-de-passer-a-un-support-commercial
• https://tekcollab.imdeo.com/java-devient-payant
• https://www.oracle.com/java/technologies/java-se-support-roadmap.html
• https://oss.oracle.com
• https://dzone.com/articles/difference-between-jdk-vs-jre-vs-jvm
• https://docs.scala-lang.org/overviews/jdk-compatibility/overview.html
• https://github.com/search?l=&o=desc&q=stars%3A%22%3E+1000%22+language%3AJava&s=stars&type=Repositories