org.apache.jackrabbit.oak.segment.file

Class ReadOnlyRevisions

java.lang.Object

org.apache.jackrabbit.oak.segment.file.ReadOnlyRevisions

All Implemented Interfaces:

Closeable, AutoCloseable, Revisions

public class ReadOnlyRevisions
extends Object
implements Revisions, Closeable

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.jackrabbit.oak.segment.Revisions

Revisions.Option

Field Summary

Fields

Modifier and Type	Field and Description
static String	JOURNAL_FILE_NAME

Constructor Summary

Constructors

Constructor and Description
ReadOnlyRevisions(File directory)

Method Summary

Modifier and Type	Method and Description
void	close() Close the underlying journal file.
RecordId	getHead() Returns the record id of the head state.
boolean	setHead(com.google.common.base.Function<RecordId,RecordId> newHead, Revisions.Option... options) Atomically set the record id of the current head state to the value returned from the newHead function when called with the record id of the current head.
boolean	setHead(RecordId expected, RecordId head, Revisions.Option... options) Atomically set the record id of the current head state to the given head state if the current head state matches the expected value.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

JOURNAL_FILE_NAME

public static final String JOURNAL_FILE_NAME

See Also:

Constant Field Values

Constructor Detail

ReadOnlyRevisions

public ReadOnlyRevisions(@Nonnull
                         File directory)
                  throws IOException

Throws:

IOException

Method Detail

getHead

@Nonnull
public RecordId getHead()

Description copied from interface: Revisions

Returns the record id of the head state. The returned id is a valid id for a SegmentNodeState.

Specified by:

getHead in interface Revisions

Returns:

id of the head state

setHead

public boolean setHead(@Nonnull
                       RecordId expected,
                       @Nonnull
                       RecordId head,
                       @Nonnull
                       Revisions.Option... options)

Description copied from interface: Revisions

Atomically set the record id of the current head state to the given head state if the current head state matches the expected value.

All record ids must be valid ids for SegmentNodeStates.

The locking behaviour of this method regarding implementation specific.

Specified by:

setHead in interface Revisions

Parameters:

expected - the expected head for the update to take place

head - the new head to update to

options - implementation specific options

Returns:

true if the current head was successfully updated, false otherwise.

setHead

public boolean setHead(@Nonnull
                       com.google.common.base.Function<RecordId,RecordId> newHead,
                       @Nonnull
                       Revisions.Option... options)
                throws InterruptedException

Description copied from interface: Revisions

Atomically set the record id of the current head state to the value returned from the newHead function when called with the record id of the current head.

All record ids must be valid ids for SegmentNodeStates.

The behaviour of this method regarding locking and handling null values returned by newHead is implementation specific.

Specified by:

setHead in interface Revisions

Parameters:

newHead - function mapping an record id to the record id to which the current head id should be set.

options - implementation specific options

Returns:

true if the current head was successfully updated, false otherwise.

Throws:

InterruptedException - Blocking implementations may throw this exception whe interrupted.

close

public void close()
           throws IOException

Close the underlying journal file.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Throws:

IOException