Different kind of Java EE projects

Question

What is the different between different kind of Java EE projects in Eclipse WTP?

There are:

• Application Client Project
• Connector Project
• Enterprise Application Project
• Utility Project

Answer 1

Quoting the Chapter 5. Projects of the RAD v7, Programming Guide (applies to Eclipse too):

• Application Client Project (J2EE) — Guides the user through creating an empty Application Client project. Includes prompts for the associated EAR project and a list of facets applicable for J2EE Application Client projects.
• Connector Project (J2EE) — Guides the user through creating a J2EE connector project, which includes specifying the associated enterprise application project and a set of facets applicable to it.
• Enterprise Application Project (J2EE) — Creates a new EAR project. This includes options for creating associated Web, EJB, and Application Client projects.
• Utility Project (J2EE) — Assists in the construction of a Java utility library project which is associated with an Enterprise Application project. The product of such a project is a JAR file that is available to the resources within the Enterprise project and is automatically wrapped into the EAR file when it is exported.

This is detailed a few pages later:

Enterprise Application project

Enterprise Application projects contain the resources needed for enterprise applications and can contain references to a combination of Web modules, EJB modules, application client modules, resource adapter modules, utility Java projects, and JAR files.

These relationships can be specified when creating a new Enterprise Application project through the wizard or through the project properties.

For more information on developing J2EE enterprise applications, see Chapter 16, “Develop Web applications using EJBs” on page 719.

J2EE Application Client project

J2EE Application Client projects contain the resources needed for J2EE application client modules. An application client module is used to contain a fully-functioning client Java application (non-Web-based) that connects to and uses the J2EE resources in a J2EE enterprise application and an application server. By holding a reference to the associated enterprise application, it shares information such as the Java Naming and Directory Interface (JNDI) reference to EJBs and data sources.

Connector project

A connector project contains the resources required for a J2EE resource adapter. The wizard allows a set of facets (including the J2EE Connector Architecture (JCA) version) and containing EAR file to be specified.

Short version: they are all wizards to create an Enterprise Application or its parts.