This topic provides the steps that are required to develop code
for a Java Platform,
Enterprise Edition (Java EE) client application.
About this task
Procedure
-
Write the client application program.
Write the Java EE
client application on any development machine. At this stage, you do not require
access to the WebSphere® Application
Server.
Rules: If you are writing a client application
program that will run on z/OS
®, the following rules apply:
- Client programs may start their own transactions but cannot join in or
start transactions in the WebSphere Application Server for z/OS run-time.
- Client application code must contain a main method.
- All input and output files for the client application must be in ASCII,
because the client run-time runs in an ASCII JVM.
-
Assemble the client application JAR file using an assembly tool.
The JNDI namespace knows what to return on a lookup because of the
information assembled by the assembly tool.
Assemble the client application
on any development machine with the assembly tool installed.
When you
assemble your client application, provide the required information to initialize
the runtime environment for your client application. For information about
how to provide the required information, see the documentation for the assembly
tool.
When you configure resources for use by your client application,
consider the following items:
- Resource environment references are different than resource references.
Resource environment references enable your client application to use a logical
name to look up a resource bound into the server JNDI namespace. A resource
reference enables your application to use a logical name to look up a local Java EE
resource. The Java EE specification does not specify a particular
implementation of a resource. The following table contains supported resource
types and identifies the resources to which the WebSphere Application Server provides
a client implementation.
Table 1. Supported resource types and resource identifiers. Supported
resource types
Resource Type |
Client Configuration Notes®
|
Client implementation provided by WebSphere Application
Server |
javax.sql.DataSource |
Supports specification of any data source
implementation class |
No |
java.net.URL |
Supports specification of custom protocol
handlers |
Provided by Java Runtime Environment files |
javax.mail.Session |
Supports custom protocol configuration |
Yes - POP3/POP3S, SMTP/SMTPS, IMAP/IMAPS |
javax.jms.QueueConnectionFactory, javax.jms.TopicConnectionFactory,
javax.jms.Queue, javax.jms.Topic |
Supports configuration of WebSphere embedded
messaging, IBM® MQ
Series and other JMS providers |
Yes - WebSphere embedded messaging |
-
Assemble the Enterprise Archive (EAR) file.
The
application is contained in an enterprise archive (EAR file). The EAR file
is composed of:
- Enterprise bean, application client, and user-defined modules or JAR files
- Web applications or WAR files
- Metadata describing the applications or application XML files
What to do next
After developing the Java EE client application code, deploy
the application onto the client machines where the client application is to
run.