The NetBeans New File wizards greatly simplify writing boilerplate code. One specific instance is the creation of JPA Controller Classes from an Entity Classes. The class file, or files, written for you will contain all the basic methods of JPA for CRUD operations on the entity or entities that you have. The only small issue is that this class is written for a standalone environment such as what you would find in an environment that does not support Context Dependency Injection. To use this class in a GlassFish environment or other container we have to make some minor changes.
When working with GlassFish the first step is to create the glassfish-resources.xml and then the persistence.xml file. If the database and its tables have not been created yet then this is the time to do this. Now create the Entity Classes from Database, also shown in the New File dialog below.