David R. Heffelfinger

This post is meant for managers, business analysts, recruiters, and anyone else who needs to interact with Java developers but is not a Java developer him/herself.
Just like any other discipline, Java development is full with lingo that may be intimidating to those not in the field.

Java
Java itself is a programming language that is platform independent, which means that Java code can run unmodified on a variety of operating systems such as Windows, Linux/Unix, and Mac OS. Traditionally source code needs to be compiled for each specific platform, this is not the case for Java.

The Java Virtual Machine
But Java is not only a programming language, it is also a platform. Java code runs on the Java Virtual Machine (JVM), which translates Java bytecode (compiled Java code) into native code for each platform. There are several other languages that run in the JVM, such as JRuby, Clojure, Groovy, Ceylon and many others.

Eclipse, NetBeans, IDEA
Java applications are typically developed using an Integrated Development Environment (IDE), the three most popular IDEs are Eclipse, NetBeans and IntelliJ IDEA.

ANT, Maven, Gradle
Java applications also typically use a build tool to help compile, build and deploy applications, the three most popular build tools are ANT, Maven and Gradle.

Java EE, JEE, J2EE
Java is extremely popular for developing enterprise server side applications, these types of applications typically use a web based user interface, with the business logic running on a server. Java Enterprise Edition (Java EE) is a set of Application Programming Interfaces (APIs) used to develop server side applications. Sometimes Java EE is referred to as JEE, however the officially sanctioned name is Java EE and the use of the term JEE is discouraged by Oracle, the company behind the Java platform (Oracle bought Sun Microsystems, the original company behind Java, back in 2010). Java EE was formerly known as J2EE, the J2EE term was so popular that it is still commonly used to refer to Java EE.

Spring
The Spring framework is an alternate set of APIs used to develop server side applications. In general, server side Java developers belong to either the Java EE or Spring camps, rare is the developer that is a fan of both.

GlassFish, Weblogic, Websphere, JBoss, Tomcat, etc
Server side Java applications are deployed to an application server. Application servers provide functionality that is common to all enterprise applications so that application developers don't have to concern themselves with implementing this functionality. For example, application servers take care of transaction management, security and scalability. Some examples of application servers include GlassFish, JBoss, WildFly, Weblogic and Websphere. Tomcat can be thought of as an application server as well, however strictly speaking, it is a servlet container, that is, it provides less functionality out of the box than full fledged application servers. Java applications written using Spring typically don't require a full fledged application server and can be deployed to Tomcat. Another popular servlet container is Jetty.

JSF, Struts, GWT, Etc
There are several Java web frameworks that are used to ease and accelerate the development of web based applications. JavaServer Faces (JSF) is the standard Java EE framework for web development. There are several JSF component libraries that run on top of JSF, these libraries make it easy to develop nice looking JSF based web applications. Some examples of these libraries include PrimeFaces, RichFaces and IceFaces. In addition to JSF, there are several other Java web frameworks such as Struts (considered by many to be a legacy framework), the Google Web Toolkit (GWT), Struts Web MVC and Wicket.

EJB
On the server side, Enterprise JavaBeans (EJBs) provide transactions, security and scalability out of the box. This frees Java developer from having to implement this functionality and allows them to focus on implementing the business logic.

JPA, Hibernate, MyBatis
There are Java APIs (Application Programming Interfaces) that help developers write code to interact with a database, the Java Persistence API (JPA) is the standard Java EE API used for this purpose. Hibernate and MyBatis (formerly known as iBatis) are two other popular libraries used for this purpose.

So there you have it, my friend, after reading this post you'll have some idea of what the heck those Java guys are talking about or what it is that is needed for that Java developer position your company is hiring for.

Anything I missed? Leave a comment.