|
|||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |
@ThreadSafe public interface Sequencer
The interface for a DNA sequencer, which sequences nodes and their content to extract additional information from the information.
Implementations must provide a no-argument constructor.
Method Summary | |
---|---|
void |
execute(javax.jcr.Node input,
String sequencedPropertyName,
NodeChange changes,
Set<RepositoryNodePath> outputPaths,
JcrExecutionContext context,
Problems problems)
Execute the sequencing operation on the supplied node, which has recently been created or changed. |
Methods inherited from interface org.jboss.dna.common.component.Component |
---|
getConfiguration, setConfiguration |
Method Detail |
---|
void execute(javax.jcr.Node input, String sequencedPropertyName, NodeChange changes, Set<RepositoryNodePath> outputPaths, JcrExecutionContext context, Problems problems) throws javax.jcr.RepositoryException, SequencerException
getting sessions
, modifying the appropriate
nodes, saving
any changes made by this sequencer, and closing
all sessions
(and any other acquired resources), even in the case of exceptions.
The SequencingService
determines the sequencers that should be executed by monitoring the changes to one or more
workspaces (it is a NodeChangeListener
registered with the ObservationService
). Changes in those workspaces
are aggregated for each transaction, and organized into changes for each node
. The SequencingService
then determines for each set of changes to a node
the set of full paths to the properties that have
changed and whether those paths match
the sequencer's
path expressions
. Each path expression produces the path to the output node,
and these output paths are accumulated and (with the original node that changed, the node change summary, and other
information) supplied to the sequencer via this method.
It is possible that a sequencer is configured to apply to multiple properties on a node. So, in cases where multiple properties are changed on a single node (within a single repository transaction), the sequencer will only be executed once. Also, in such cases the sequencer's configuration may imply multiple output nodes, so it is left to the sequencer to define the behavior in such cases.
input
- the node that has recently been created or changed; never nullsequencedPropertyName
- the name of the property that caused this sequencer to be executed; never null and never emptychanges
- the immutable summary of changes that occurred on the input
node within the transaction; never
nulloutputPaths
- the paths to the nodes where the sequencing content should be placed; never null and never empty, but
the set may contain paths for non-existant nodes or may reference the input
nodecontext
- the context in which this sequencer is executing; never nullproblems
- the interface used for recording problems; never null
javax.jcr.RepositoryException
- if there is a problem while working with the repository
SequencerException
- if there is an error in this sequencer
|
|||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |