Below are a definition, preconditions for installing and uninstalling, and an example of a deployable unit.
What is a deployable unit?
A deployable unit is a jar file that can be installed in the SLEE. It contains:
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a deployment descriptor
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constituent jar files, with Java class files and deployment descriptors for components such as:
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SBBs
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events
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profile specifications
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resource adaptor types
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resource adaptors
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libraries
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XML files for services.
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The JAIN SLEE 1.1 specification defines the structure of a deployable unit. |
Installing and uninstalling deployable units
You must install and uninstall deployable units in a particular order, according to the dependencies of the SLEE components they contain. You cannot install a deployable unit unless either it contains all of its dependencies, or they are already installed. For example, if your deployable unit contains an SBB which depends on a library jar, the library jar must either already be installed in the SLEE, or be included in that same deployable unit jar.
Pre-conditions
A deployable unit cannot be installed if any of the following is true:
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A deployable unit with the same URL has already been installed in the SLEE.
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The deployable unit contains a component with the same name, vendor and version as a component of the same type that is already installed in the SLEE.
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The deployable unit contains a component that references other components that are not yet installed in the SLEE and are not included in the deployable unit jar. (For example, an SBB component may reference event-type components and profile-specification components that are not included or pre-installed.)
A deployable unit cannot be uninstalled if either of the following is true:
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There are any dependencies on any of its components from components in other installed deployable units. For example, if a deployable unit contains an SBB jar that depends on a profile-specification jar contained in a second deployable unit, the deployable unit containing the profile-specification jar cannot be uninstalled while the deployable unit containing the SBB jar remains installed.
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There are "instances" of components contained in the deployable unit. For example, a deployable unit containing a resource adaptor cannot be uninstalled if the SLEE includes resource adaptor entities of that resource adaptor.
Deployable unit example
The following example illustrates the deployment descriptor for a deployable unit jar file:
<deployable-unit> <description> ... </description> ... <jar> SomeProfileSpec.jar </jar> <jar> BarAddressProfileSpec.jar </jar> <jar> SomeCustomEvent.jar </jar> <jar> FooSBB.jar </jar> <jar> BarSBB.jar </jar> ... <service-xml> FooService.xml </service-xml> ... </deployable-unit>
The content of the deployable unit jar file is as follows:
META-INF/deployable-unit.xml META-INF/MANIFEST.MF ... SomeProfileSpec.jar BarAddressProfileSpec.jar SomeCustomEvent.jar FooSBB.jar BarSBB.jar FooService.xml ...
