MACROMEDIA 38000382 - Macromedia JRun - Mac, Getting Started Manual

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52 Chapter 5 Introduction to EJB
Using EJB in JRun
This section describes features and functionality unique to the JRun EJB architecture.
Stubless deployment
One of the main JRun EJB features is stubless deployment . There is no JRun EJB
deployment tool. You compile the EJBs, package them in a JAR file (optional), copy the
compiled EJB interfaces to the client, and define this location in the client classpath. The
JRun instance proxy handles the functionality formerly managed by the stubs.
Deployment options
JRun provides a flexible EJB deployment model that makes it easy to develop and deploy
beans. The following table describes the features of this deployment model:
EJB clustering
When running EJBs in a JRun server that is part of a cluster, JRun enables load balancing
and failover, ensuring high performance and reliability.
JRun also enables EJB clustering by default. To disable EJB clustering, set the
cluster-home
and
cluster-object
elements in the jrun-ejb-jar.xml file to false.
Note: JRun does not enable EJB clustering for local beans.
For more information see JRun Administrator’s Guide.
Deployment feature Description
Hot deploy If hot deploy is enabled, you can deploy an EJB by copying its JAR
file or directory structure into a deploy directory. By default, the
JRun server root directory is set for hot deployment. To test this
feature, start the samples JRun server and copy an EJB to the
jrun_root /servers/samples directory.
When hot deploy is enabled, the JRun deployer detects changes
to the EJB deployment descriptor and automatically redeploys the
bean.
Additionally, when enabled, this feature deploys EJBs created for
other application servers, including the Sun reference
implementation and JRun 3.1.
Run from JAR or open
directory JRun can run your EJB from a JAR file or from an open directory
structure. When the JRun deployer finds a META-INF/ejb-jar.xml
file, it deploys the EJBs specified in the file. Running from an open
directory structure is particularly useful during the EJB
development cycle because it eliminates many steps in the
traditional EJB deployment and redeployment process.