When you develop J2EE applications,
you can specify the server runtime environments for your J2EE projects. The
target server is specified during project creation and import, and it can
be changed in the project properties. The target server setting is the default
mechanism for setting the class path for J2EE projects.
In
order to support different application servers that use different JDK levels
for their Java™ Runtime Environment (JRE), the workbench prompts
you for a target server setting for each J2EE project. For example, if you
want to take advantage of the features of JDK 1.4.2, your applications require
different class path entries than those that were used in previous versions
of the workbench. By prompting you to specify a target server, the workbench
enforces that proper entries are added for running on the server you choose.
You
can also add more than one target server for your project. In this case, the
workbench prevents you from adding any facets not supported by all of the
target servers. If you add more than one target server, choose a server that
will contribute to the project's class path as the primary server.
When
the project is created, the class path of the project is updated with two
class path containers. One container is the JDK container and the other is
the server container. The JDK container points to the directory that contains
the JAR files that are necessary to support the JDK version. The server container
points to the directory that contains the multiple public JAR files available
in the selected server. The project then compiles based on the required JAR
files located in these folders, and you do not need to worry about adding
additional JAR files from the server during development. When the project
is compiled, the JAR files are included in the class path. You can still add
your own JAR files to the class path.
The target runtime environment
is specified in the org.eclipse.wst.common.project.facet.core.xml file in
the project's .settings folder. You should not edit this file manually; instead,
use the properties window as described in this topic.
All J2EE project
creation and import wizards prompt you to specify the target server for the
resulting projects. The list of target servers that you can choose from is
filtered based on installed runtimes, the J2EE level of the application, and
the J2EE module type. For example, for EJB projects only application servers
that support Enterprise JavaBeans™ are displayed. All projects
inside a single EAR file must be targeted to the same server. If you create
a new project and add it to an existing EAR project during creation, the project
inherits the target server setting of the EAR project.
Note: Utility Java projects
that are added to an application are targeted to the same target server as
the application. Web library projects that are added to a Web project are
targeted to the same target server as the Web project.
To modify
the target runtime and default server for an existing project, complete the
following steps: