The Java EE 6 Tutorial

Packaging Enterprise Beans in WAR Modules

Enterprise beans often provide the business logic of a web application. In these cases, packaging the enterprise bean within the web application’s WAR module simplifies deployment and application organization. Enterprise beans may be packaged within a WAR module as Java programming language class files or within a JAR file that is bundled within the WAR module.

To include enterprise bean class files in a WAR module, the class files should be in the WEB-INF/classes directory.

To include a JAR file that contains enterprise beans in a WAR module, add the JAR to the WEB-INF/lib directory of the WAR module.

WAR modules that contain enterprise beans do not require an ejb-jar.xml deployment descriptor. If the application uses ejb-jar.xml, it must be located in the WAR module’s WEB-INF directory.

JAR files that contain enterprise bean classes packaged within a WAR module are not considered EJB JAR files, even if the bundled JAR file conforms to the format of an EJB JAR file. The enterprise beans contained within the JAR file are semantically equivalent to enterprise beans located in the WAR module’s WEB-INF/classes directory, and the environment namespace of all the enterprise beans are scoped to the WAR module.

For example, suppose that a web application consists of a shopping cart enterprise bean, a credit card processing enterprise bean, and a Java servlet front end. The shopping cart bean exposes a local, no-interface view and is defined as follows:

package com.example.cart;

public class CartBean { ... }

The credit card processing bean is packaged within its own JAR file, cc.jar, exposes a local, no-interface view, and is defined as follows:


public class CreditCardBean { ... }

The servlet, com.example.web.StoreServlet, handles the web front end and uses both CartBean and CreditCardBean. The WAR module layout for this application looks as follows: