HP Integrity NonStop H-Series - Manual (Page 50)

Table 11 Elements of EE subsystem (continued)
Description Element
NOTE: Module dependencies can also be defined by one of the JBoss
specific deployment descriptors such
asjboss-deployment-structure.xml.
A flag indicating whether each of the sub deployments within a .ear
can access classes belonging to another sub deployment within the same ear-subdeployments-isolated
.ear . If this is set to false, the classes belonging to other sub
deployments within the .ear become visible to the sub deployment. For
example, if an EAR contains web.war, ejb1.jar, ejb2.jar and if
the flag is set to false, then the classes in web.war can access classes
belonging to ejb1.jar and ejb2.jar. Similarly classes in ejb1.jar
can access classes in ejb2.jar and vice-versa. Note, that this flag has
no effect on the isolated classloader of the .war file(s). That is,
irrespective of whether this flag is set to true or false, the .war within
a .ear has an isolated classloader and other sub deployments within
that .ear are not able to access classes from that .war.
As per the Java EE specification, a Java EE component’s behavior can
be configured either through annotations or through the deployment spec-descriptor-property-replacement
descriptor (ejb-jar.xml is the deployment descriptor for EJBs). There
can be situations where configuration property needs to change per
deployment. For example connectionParameters property of an
MDB can be different in different environments. A change in the value
can be effected by changing the ejb-jar.xml. But this is same as
repackaging the deployment itself as the ejb-jar.xml is part of the
deployment package. JBoss provides a feature where a Java EE
configuration parameter can be read from a set of system properties.
With this feature the deployment descriptor need not be modified to effect
the necessary change, rather a system property needs to be introduced.
Here a change to the value of connectionParameters can be effected
by providing a value of the JVM system property
jms.connection.parameters
. The following snippet of
ejb-jar.xml that configures the necessary properties for an MDB
illustrates this:
.......
.......
connectionParameters
${jms.connection.parameters:'host=localhost;port=5445'}
........
.........
Setting this property to true enables substitution of the Java EE descriptors
ejb-jar.xml
and persistence.xml. By default, substitution of Java
EE descriptors is disabled.
This property allows substitution of properties in the following JBoss
specific descriptors: jboss-descriptor-property-replacement
•
jboss-ejb3.xml
•
jboss-app.xml
•
*-jms.xml
•
*-ds.xml
50 Configuring NSASJ