org.eclipse.jgit.internal.storage.reftable

Class ReftableWriter

java.lang.Object

org.eclipse.jgit.internal.storage.reftable.ReftableWriter

public class ReftableWriter
extends Object

Writes a reftable formatted file.

A reftable can be written in a streaming fashion, provided the caller sorts all references. A ReftableWriter is single-use, and not thread-safe.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ReftableWriter.Stats Statistics about a written reftable.

Constructor Summary

Constructors

Constructor and Description
ReftableWriter(OutputStream os) Initialize a writer with a default configuration.
ReftableWriter(ReftableConfig cfg, OutputStream os) Initialize a writer with a configuration.

Method Summary

Modifier and Type	Method and Description
ReftableWriter	begin() Begin writing the reftable.
void	deleteLog(String ref, long updateIndex) Record deletion of one reflog entry in this reftable.
long	estimateTotalBytes() Get an estimate of the current size in bytes of the reftable
ReftableWriter	finish() Finish writing the reftable by writing its trailer.
ReftableWriter.Stats	getStats() Get statistics of the last written reftable.
ReftableWriter	setConfig(ReftableConfig cfg) Set configuration for the writer.
ReftableWriter	setMaxUpdateIndex(long max) Set the maximum update index for log entries that appear in this reftable.
ReftableWriter	setMinUpdateIndex(long min) Set the minimum update index for log entries that appear in this reftable.
ReftableWriter	sortAndWriteRefs(Collection<Ref> refsToPack) Sort a collection of references and write them to the reftable.
void	writeLog(String ref, long updateIndex, PersonIdent who, ObjectId oldId, ObjectId newId, String message) Write one reflog entry to the reftable.
void	writeRef(Ref ref) Write one reference to the reftable.
void	writeRef(Ref ref, long updateIndex) Write one reference to the reftable.

Methods inherited from class java.lang.Object

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

Constructor Detail

ReftableWriter

public ReftableWriter(OutputStream os)

Initialize a writer with a default configuration.

Parameters:

os - output stream.

ReftableWriter

public ReftableWriter(ReftableConfig cfg,
                      OutputStream os)

Initialize a writer with a configuration.

Parameters:

cfg - configuration for the writer

os - output stream.

Method Detail

setConfig

public ReftableWriter setConfig(ReftableConfig cfg)

Set configuration for the writer.

Parameters:

cfg - configuration for the writer.

Returns:

this

setMinUpdateIndex

public ReftableWriter setMinUpdateIndex(long min)

Set the minimum update index for log entries that appear in this reftable.

Parameters:

min - the minimum update index for log entries that appear in this reftable. This should be 1 higher than the prior reftable's maxUpdateIndex if this table will be used in a stack.

Returns:

this

setMaxUpdateIndex

public ReftableWriter setMaxUpdateIndex(long max)

Set the maximum update index for log entries that appear in this reftable.

Parameters:

max - the maximum update index for log entries that appear in this reftable. This should be at least 1 higher than the prior reftable's maxUpdateIndex if this table will be used in a stack.

Returns:

this

begin

public ReftableWriter begin()

Begin writing the reftable. Should be called only once. Call this if a stream was passed to the constructor.

Returns:

this

sortAndWriteRefs

public ReftableWriter sortAndWriteRefs(Collection<Ref> refsToPack)
                                throws IOException

Sort a collection of references and write them to the reftable. The input refs may not have duplicate names.

Parameters:

refsToPack - references to sort and write.

Returns:

this

Throws:

IOException - if reftable cannot be written.

writeRef

public void writeRef(Ref ref)
              throws IOException

Write one reference to the reftable.

References must be passed in sorted order.

Parameters:

ref - the reference to store.

Throws:

IOException - if reftable cannot be written.

writeRef

public void writeRef(Ref ref,
                     long updateIndex)
              throws IOException

Write one reference to the reftable.

References must be passed in sorted order.

Parameters:

ref - the reference to store.

updateIndex - the updateIndex that modified this reference. Must be >= minUpdateIndex for this file.

Throws:

IOException - if reftable cannot be written.

writeLog

public void writeLog(String ref,
                     long updateIndex,
                     PersonIdent who,
                     ObjectId oldId,
                     ObjectId newId,
                     @Nullable
                     String message)
              throws IOException

Write one reflog entry to the reftable.

Reflog entries must be written in reference name and descending updateIndex (highest first) order.

Parameters:

ref - name of the reference.

updateIndex - identifier of the transaction that created the log record. The updateIndex must be unique within the scope of ref, and must be within the bounds defined by minUpdateIndex <= updateIndex <= maxUpdateIndex.

who - committer of the reflog entry.

oldId - prior id; pass ObjectId.zeroId() for creations.

newId - new id; pass ObjectId.zeroId() for deletions.

message - optional message (may be null).

Throws:

IOException - if reftable cannot be written.

deleteLog

public void deleteLog(String ref,
                      long updateIndex)
               throws IOException

Record deletion of one reflog entry in this reftable.

The deletion can shadow an entry stored in a lower table in the stack. This is useful for refs/stash and dropping an entry from its reflog.

Deletion must be properly interleaved in sorted updateIndex order with any other logs written by writeLog(String, long, PersonIdent, ObjectId, ObjectId, String).

Parameters:

ref - the ref to delete (hide) a reflog entry from.

updateIndex - the update index that must be hidden.

Throws:

IOException - if reftable cannot be written.

estimateTotalBytes

public long estimateTotalBytes()

Get an estimate of the current size in bytes of the reftable

Returns:

an estimate of the current size in bytes of the reftable, if it was finished right now. Estimate is only accurate if ReftableConfig.setIndexObjects(boolean) is false and ReftableConfig.setMaxIndexLevels(int) is 1.

finish

public ReftableWriter finish()
                      throws IOException

Finish writing the reftable by writing its trailer.

Returns:

this

Throws:

IOException - if reftable cannot be written.

getStats

public ReftableWriter.Stats getStats()

Get statistics of the last written reftable.

Returns:

statistics of the last written reftable.