Package org.eclipse.jgit.internal.storage.file

Class FileReftableDatabase

java.lang.Object

org.eclipse.jgit.lib.RefDatabase

org.eclipse.jgit.internal.storage.file.FileReftableDatabase

public class FileReftableDatabase
extends RefDatabase

Implements RefDatabase using reftable for storage. This class is threadsafe.

Field Summary

Fields inherited from class org.eclipse.jgit.lib.RefDatabase

ALL, MAX_SYMBOLIC_REF_DEPTH, SEARCH_PATH

Method Summary

Modifier and Type	Method	Description
void	close()	Close any resources held by this database.
void	compactFully()	Runs a full compaction for GC purposes.
static FileReftableDatabase	convertFrom(FileRepository repo, boolean writeLogs)
void	create()	Initialize a new reference database at this location.
Ref	exactRef(String name)	Read a single reference.
List<Ref>	getAdditionalRefs()	Get the additional reference-like entities from the repository.
List<Ref>	getRefs()	Returns all refs.
Map<String,Ref>	getRefs(String prefix)	Get a section of the reference namespace.
List<Ref>	getRefsByPrefixWithExclusions(String include, Set<String> excludes)	Returns refs whose names start with a given prefix excluding all refs that start with one of the given prefixes.
boolean	hasFastTipsWithSha1()	If the ref database does not support fast inverse queries, it may be advantageous to build a complete SHA1 to ref map in advance for multiple uses.
boolean	isNameConflicting(String name)	Determine if a proposed reference name overlaps with an existing one.
static boolean	isReftable(File repoDir)
BatchRefUpdate	newBatchUpdate()	Create a new batch update to attempt on this database.
RefRename	newRename(String fromName, String toName)	Create a new update command to rename a reference.
RefUpdate	newUpdate(String refName, boolean detach)	Create a new update command to create, modify or delete a reference.
Ref	peel(Ref ref)	Peel a possibly unpeeled reference by traversing the annotated tags.
boolean	performsAtomicTransactions()	Whether the database is capable of performing batch updates as atomic transactions.

Methods inherited from class org.eclipse.jgit.lib.RefDatabase

exactRef, findRef, findRef, firstExactRef, getConflictingNames, getRef, getRefsByPrefix, getRefsByPrefix, getTipsWithSha1, hasRefs, hasVersioning, refresh

Methods inherited from class java.lang.Object

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

Method Detail

isReftable

public static boolean isReftable(File repoDir)

Parameters:

repoDir -

Returns:

whether the given repo uses reftable for refdb storage.

hasFastTipsWithSha1

public boolean hasFastTipsWithSha1()
                            throws IOException

If the ref database does not support fast inverse queries, it may be advantageous to build a complete SHA1 to ref map in advance for multiple uses. To let applications decide on this decision, this function indicates whether the inverse map is available.

Overrides:

hasFastTipsWithSha1 in class RefDatabase

Returns:

whether this RefDatabase supports fast inverse ref queries.

Throws:

IOException - on I/O problems.

compactFully

public void compactFully()
                  throws IOException

Runs a full compaction for GC purposes.

Throws:

IOException - on I/O errors

performsAtomicTransactions

public boolean performsAtomicTransactions()

Whether the database is capable of performing batch updates as atomic transactions.

If true, by default BatchRefUpdate instances will perform updates atomically, meaning either all updates will succeed, or all updates will fail. It is still possible to turn off this behavior on a per-batch basis by calling update.setAtomic(false).

If false, BatchRefUpdate instances will never perform updates atomically, and calling update.setAtomic(true) will cause the entire batch to fail with REJECTED_OTHER_REASON.

This definition of atomicity is stronger than what is provided by ReceivePack. ReceivePack will attempt to reject all commands if it knows in advance some commands may fail, even if the storage layer does not support atomic transactions. Here, atomicity applies even in the case of unforeseeable errors.

Overrides:

performsAtomicTransactions in class RefDatabase

Returns:

whether transactions are atomic by default.

newBatchUpdate

@NonNull
public BatchRefUpdate newBatchUpdate()

Create a new batch update to attempt on this database.

The default implementation performs a sequential update of each command.

Overrides:

newBatchUpdate in class RefDatabase

Returns:

a new batch update object.

newUpdate

public RefUpdate newUpdate(String refName,
                           boolean detach)
                    throws IOException

Create a new update command to create, modify or delete a reference.

Specified by:

newUpdate in class RefDatabase

Parameters:

refName - the name of the reference.

detach - if true and name is currently a SymbolicRef, the update will replace it with an ObjectIdRef. Otherwise, the update will recursively traverse SymbolicRefs and operate on the leaf ObjectIdRef.

Returns:

a new update for the requested name; never null.

Throws:

IOException - the reference space cannot be accessed.

exactRef

public Ref exactRef(String name)
             throws IOException

Read a single reference.

Unlike RefDatabase.findRef(java.lang.String), this method expects an unshortened reference name and does not search using the standard RefDatabase.SEARCH_PATH.

Specified by:

exactRef in class RefDatabase

Parameters:

name - the unabbreviated name of the reference.

Returns:

the reference (if it exists); else null.

Throws:

IOException - the reference space cannot be accessed.

getRefs

public List<Ref> getRefs()
                  throws IOException

Returns all refs.

This includes HEAD, branches under ref/heads/, tags under refs/tags/, etc. It does not include pseudo-refs like FETCH_HEAD; for those, see RefDatabase.getAdditionalRefs().

Symbolic references to a non-existent ref (for example, HEAD pointing to a branch yet to be born) are not included.

Callers interested in only a portion of the ref hierarchy can call RefDatabase.getRefsByPrefix(java.lang.String) instead.

Overrides:

getRefs in class RefDatabase

Returns:

immutable list of all refs.

Throws:

IOException - the reference space cannot be accessed.

getRefs

public Map<String,Ref> getRefs(String prefix)
                              throws IOException

Get a section of the reference namespace.

Specified by:

getRefs in class RefDatabase

Parameters:

prefix - prefix to search the namespace with; must end with /. If the empty string (RefDatabase.ALL), obtain a complete snapshot of all references.

Returns:

modifiable map that is a complete snapshot of the current reference namespace, with prefix removed from the start of each key. The map can be an unsorted map.

Throws:

IOException - the reference space cannot be accessed.

getRefsByPrefixWithExclusions

public List<Ref> getRefsByPrefixWithExclusions(String include,
                                               Set<String> excludes)
                                        throws IOException

Returns refs whose names start with a given prefix excluding all refs that start with one of the given prefixes.

The default implementation is not efficient. Implementors of RefDatabase should override this method directly if a better implementation is possible.

Overrides:

getRefsByPrefixWithExclusions in class RefDatabase

Parameters:

include - string that names of refs should start with; may be empty.

excludes - strings that names of refs can't start with; may be empty.

Returns:

immutable list of refs whose names start with prefix and none of the strings in exclude.

Throws:

IOException - the reference space cannot be accessed.

getAdditionalRefs

public List<Ref> getAdditionalRefs()
                            throws IOException

Get the additional reference-like entities from the repository.

The result list includes non-ref items such as MERGE_HEAD and FETCH_RESULT cast to be refs. The names of these refs are not returned by getRefs() but are accepted by RefDatabase.findRef(String) and RefDatabase.exactRef(String).

Specified by:

getAdditionalRefs in class RefDatabase

Returns:

a list of additional refs

Throws:

IOException - the reference space cannot be accessed.

peel

public Ref peel(Ref ref)
         throws IOException

Peel a possibly unpeeled reference by traversing the annotated tags.

If the reference cannot be peeled (as it does not refer to an annotated tag) the peeled id stays null, but Ref.isPeeled() will be true.

Implementors should check Ref.isPeeled() before performing any additional work effort.

Specified by:

peel in class RefDatabase

Parameters:

ref - The reference to peel

Returns:

ref if ref.isPeeled() is true; otherwise a new Ref object representing the same data as Ref, but isPeeled() will be true and getPeeledObjectId() will contain the peeled object (or null).

Throws:

IOException - the reference space or object space cannot be accessed.

newRename

public RefRename newRename(String fromName,
                           String toName)
                    throws IOException

Create a new update command to rename a reference.

Specified by:

newRename in class RefDatabase

Parameters:

fromName - name of reference to rename from

toName - name of reference to rename to

Returns:

an update command that knows how to rename a branch to another.

Throws:

IOException - the reference space cannot be accessed.

isNameConflicting

public boolean isNameConflicting(String name)
                          throws IOException

Determine if a proposed reference name overlaps with an existing one.

Reference names use '/' as a component separator, and may be stored in a hierarchical storage such as a directory on the local filesystem.

If the reference "refs/heads/foo" exists then "refs/heads/foo/bar" must not exist, as a reference cannot have a value and also be a container for other references at the same time.

If the reference "refs/heads/foo/bar" exists than the reference "refs/heads/foo" cannot exist, for the same reason.

Specified by:

isNameConflicting in class RefDatabase

Parameters:

name - proposed name.

Returns:

true if the name overlaps with an existing reference; false if using this name right now would be safe.

Throws:

IOException - the database could not be read to check for conflicts.

See Also:

RefDatabase.getConflictingNames(String)

close

public void close()

Close any resources held by this database.

Specified by:

close in class RefDatabase

create

public void create()
            throws IOException

Initialize a new reference database at this location.

Specified by:

create in class RefDatabase

Throws:

IOException - the database could not be created.

convertFrom

public static FileReftableDatabase convertFrom(FileRepository repo,
                                               boolean writeLogs)
                                        throws IOException

Parameters:

repo - the repository

writeLogs - whether to write reflogs

Returns:

a reftable based RefDB from an existing repository.

Throws:

IOException - on IO error