This tutorial is a guide to developing enterprise applications for the Java Platform, Enterprise Edition 7 (Java EE 7) using GlassFish Server Open Source Edition.Oracle GlassFish Server, a Java EE compatible application server, is based on GlassFish Server Open Source Edition, the leading open-source and open-community platform for building and deploying next-generation applications and services. GlassFish Server Open Source Edition, developed by the GlassFish project open-source community at https://glassfish.java.net/, is the first compatible implementation of the Java EE 7 platform specification. This lightweight, flexible, and open-source application server enables organizations not only to leverage the new capabilities introduced within the Java EE 7 specification, but also to add to their existing capabilities through a faster and more streamlined development and deployment cycle. Oracle GlassFish Server, the product version, and GlassFish Server Open Source Edition, the open-source version, are hereafter referred to as GlassFish Server.