OSGi™ Service Platform
Release 4

org.osgi.service.deploymentadmin.spi
Interface ResourceProcessor


public interface ResourceProcessor

ResourceProcessor interface is implemented by processors handling resource files in deployment packages. Resource Processors expose their services as standard OSGi services. Bundles exporting the service may arrive in the deployment package (customizers) or may be preregistered (they are installed prevoiusly). Resource processors has to define the service.pid standard OSGi service property which should be a unique string.

The order of the method calls on a particular Resource Processor in case of install/update session is the following:

  1. begin(DeploymentSession)
  2. process(String, InputStream) calls till there are resources to process or rollback() and the further steps are ignored
  3. dropped(String) calls till there are resources to drop
  4. prepare()
  5. commit() or rollback()
The order of the method calls on a particular Resource Processor in case of uninstall session is the following:

  1. begin(DeploymentSession)
  2. dropAllResources() or rollback() and the further steps are ignored
  3. prepare()
  4. commit() or rollback()


Method Summary
 void begin(DeploymentSession session)
          Called when the Deployment Admin starts a new operation on the given deployment package, and the resource processor is associated a resource within the package.
 void cancel()
          Processing of a resource passed to the resource processor may take long.
 void commit()
          Called when the processing of the current deployment package is finished.
 void dropAllResources()
          This method is called during an "uninstall" deployment session.
 void dropped(java.lang.String resource)
          Called when a resource, associated with a particular resource processor, had belonged to an earlier version of a deployment package but is not present in the current version of the deployment package.
 void prepare()
          This method is called on the Resource Processor immediately before calling the commit method.
 void process(java.lang.String name, java.io.InputStream stream)
          Called when a resource is encountered in the deployment package for which this resource processor has been selected to handle the processing of that resource.
 void rollback()
          Called when the processing of the current deployment package is finished.
 

Method Detail

begin

public void begin(DeploymentSession session)
Called when the Deployment Admin starts a new operation on the given deployment package, and the resource processor is associated a resource within the package. Only one deployment package can be processed at a time.

Parameters:
session - object that represents the current session to the resource processor
See Also:
DeploymentSession

process

public void process(java.lang.String name,
                    java.io.InputStream stream)
             throws ResourceProcessorException
Called when a resource is encountered in the deployment package for which this resource processor has been selected to handle the processing of that resource.

Parameters:
name - The name of the resource relative to the deployment package root directory.
stream - The stream for the resource.
Throws:
ResourceProcessorException - if the resource cannot be processed. Only ResourceProcessorException.CODE_RESOURCE_SHARING_VIOLATION and ResourceProcessorException.CODE_OTHER_ERROR error codes are allowed.

dropped

public void dropped(java.lang.String resource)
             throws ResourceProcessorException
Called when a resource, associated with a particular resource processor, had belonged to an earlier version of a deployment package but is not present in the current version of the deployment package. This provides an opportunity for the processor to cleanup any memory and persistent data being maintained for the particular resource. This method will only be called during "update" deployment sessions.

Parameters:
resource - the name of the resource to drop (it is the same as the value of the "Name" attribute in the deployment package's manifest)
Throws:
ResourceProcessorException - if the resource is not allowed to be dropped. Only the ResourceProcessorException.CODE_OTHER_ERROR error code is allowed

dropAllResources

public void dropAllResources()
                      throws ResourceProcessorException
This method is called during an "uninstall" deployment session. This method will be called on all resource processors that are associated with resources in the deployment package being uninstalled. This provides an opportunity for the processor to cleanup any memory and persistent data being maintained for the deployment package.

Throws:
ResourceProcessorException - if all resources could not be dropped. Only the ResourceProcessorException.CODE_OTHER_ERROR is allowed.

prepare

public void prepare()
             throws ResourceProcessorException
This method is called on the Resource Processor immediately before calling the commit method. The Resource Processor has to check whether it is able to commit the operations since the last begin method call. If it determines that it is not able to commit the changes, it has to raise a ResourceProcessorException with the ResourceProcessorException.CODE_PREPARE error code.

Throws:
ResourceProcessorException - if the resource processor is able to determine it is not able to commit. Only the ResourceProcessorException.CODE_PREPARE error code is allowed.

commit

public void commit()
Called when the processing of the current deployment package is finished. This method is called if the processing of the current deployment package was successful, and the changes must be made permanent.


rollback

public void rollback()
Called when the processing of the current deployment package is finished. This method is called if the processing of the current deployment package was unsuccessful, and the changes made during the processing of the deployment package should be removed.


cancel

public void cancel()
Processing of a resource passed to the resource processor may take long. The cancel() method notifies the resource processor that it should interrupt the processing of the current resource. This method is called by the DeploymentAdmin implementation after the DeploymentAdmin.cancel() method is called.


OSGi™ Service Platform
Release 4

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