Package org.apache.jackrabbit.oak.segment.scheduler

Interface Scheduler

All Known Implementing Classes:

LockBasedScheduler

public interface Scheduler

A Scheduler instance transforms changes to the content tree into a queue of commits.

An implementation is free to employ any scheduling strategy as long as it guarantees all changes are applied atomically without changing the semantics of the changes recorded in the NodeBuilder or the semantics of the CommitHook contained in the actual Commit passed to the schedule method.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static interface	Scheduler.SchedulerOption	Scheduling options for parametrizing individual commits.

Method Summary

Modifier and Type	Method	Description
String	checkpoint(long lifetime, @NotNull Map<String,String> properties)	Creates a new checkpoint of the latest root of the tree.
NodeState	getHeadNodeState()	Returns the latest state of the tree.
boolean	removeCheckpoint(String name)	Releases the provided checkpoint.
NodeState	schedule(@NotNull Commit commit, Scheduler.SchedulerOption... schedulingOptions)	Schedule a commit.

Method Detail

schedule

NodeState schedule(@NotNull
                   @NotNull Commit commit,
                   Scheduler.SchedulerOption... schedulingOptions)
            throws CommitFailedException

Schedule a commit. This method blocks until the changes in this commit have been processed and persisted. That is, until a call to getHeadNodeState() would return a node state reflecting those changes.

Parameters:

commit - the commit

schedulingOptions - implementation specific scheduling options

Throws:

CommitFailedException - if the commit failed and none of the changes have been applied.

checkpoint

String checkpoint(long lifetime,
                  @NotNull
                  @NotNull Map<String,String> properties)

Creates a new checkpoint of the latest root of the tree. The checkpoint remains valid for at least as long as requested and allows that state of the repository to be retrieved using the returned opaque string reference.

The properties passed to this methods are associated with the checkpoint and can be retrieved through the NodeStore.checkpointInfo(String) method. Its semantics is entirely application specific.

Parameters:

lifetime - time (in milliseconds, > 0) that the checkpoint should remain available

properties - properties to associate with the checkpoint

Returns:

string reference of this checkpoint

removeCheckpoint

boolean removeCheckpoint(String name)

Releases the provided checkpoint. If the provided checkpoint doesn't exist this method should return true.

Parameters:

name - string reference of a checkpoint

Returns:

true if the checkpoint was successfully removed, or if it doesn't exist

getHeadNodeState

NodeState getHeadNodeState()

Returns the latest state of the tree.

Returns:

the latest state.