Red Hat Application Server, Manual

Page: 191 / 296

Chapter 23.
EAR Packaging
This chapter is for the Application Assembler; that is, the person in charge of combining one or more
J2EE components (EJB-JARs and/or WARs) to create a J2EE application. It describes how the J2EE
components should be packaged to create a J2EE application.
23.1. Principles
J2EE applications are packaged for deployment in a standard Java programming language Archive
file called an EAR file (Enterprise ARchive). This file can contain the following:
The web components (WAR)
One or more WARs that contain the web components of the J2EE application. Due to the class
loader hierarchy, when the WARs are packaged in a J2EE application, it is not necessary to
package bean classes in the
WEB-INF/lib
directory.
Details about this class loader hierarchy are described in Chapter 5 JOnAS Class Loader Hierar-
chy .
The beans (EJB-JAR)
One or more EJB-JARs, which contain the beans of the J2EE application.
The libraries (JAR)
One or more jars which contain the libraries (tag libraries and any utility libraries) used for the
J2EE application.
The J2EE deployment descriptor
The standard XML deployment descriptor in the format defined in the J2EE
1.4 specification (refer to
$JONAS_ROOT/xml/application_1_5.xsd
or
http://java.sun.com/xml/ns/j2ee/connector_1_5.xsd). This deployment descriptor must be stored
with the name
META-INF/application.xml
in the EAR file.
23.1.1. EAR Packaging Example
Before building an EAR file for a J2EE application, the EJB-JARs and the WARs that will be packaged
in the J2EE application must be built and the XML deployment descriptor (
application.xml
) must
be written.
Then, the EAR file (
Ä
j2ee-application
Å
.ear
) can be built using the
jar
command:
cd
Ä
your_j2ee_application_directory
Å
jar cvf
Ä
j2ee-application
Å
.ear *