Package com.google.gerrit.server.notedb

Class RepoSequence

java.lang.Object

com.google.gerrit.server.notedb.RepoSequence

public class RepoSequence
extends Object

Class for managing an incrementing sequence backed by a git repository.

The current sequence number is stored as UTF-8 text in a blob pointed to by a ref in the refs/sequences/* namespace. Multiple processes can share the same sequence by incrementing the counter using normal git ref updates. To amortize the cost of these ref updates, processes can increment the counter by a larger number and hand out numbers from that range in memory until they run out. This means concurrent processes will hand out somewhat non-monotonic numbers.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	RepoSequence.Seed

Constructor Summary

Constructors

Constructor	Description
RepoSequence(GitRepositoryManager repoManager, GitReferenceUpdated gitRefUpdated, Project.NameKey projectName, String name, RepoSequence.Seed seed, int batchSize)
RepoSequence(GitRepositoryManager repoManager, GitReferenceUpdated gitRefUpdated, Project.NameKey projectName, String name, RepoSequence.Seed seed, int batchSize, int floor)

Method Summary

Modifier and Type	Method	Description
int	next()	Retrieves the next available sequence number.
com.google.common.collect.ImmutableList<Integer>	next(int count)	Retrieves the next N available sequence number.
static org.eclipse.jgit.transport.ReceiveCommand	storeNew(org.eclipse.jgit.lib.ObjectInserter ins, String name, int val)

Methods inherited from class java.lang.Object

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

Constructor Detail

RepoSequence

public RepoSequence(GitRepositoryManager repoManager,
                    GitReferenceUpdated gitRefUpdated,
                    Project.NameKey projectName,
                    String name,
                    RepoSequence.Seed seed,
                    int batchSize)

RepoSequence

public RepoSequence(GitRepositoryManager repoManager,
                    GitReferenceUpdated gitRefUpdated,
                    Project.NameKey projectName,
                    String name,
                    RepoSequence.Seed seed,
                    int batchSize,
                    int floor)

Method Detail

next

public int next()

Retrieves the next available sequence number.

This method is thread-safe.

Returns:

the next available sequence number

next

public com.google.common.collect.ImmutableList<Integer> next(int count)

Retrieves the next N available sequence number.

This method is thread-safe.

Parameters:

count - the number of sequence numbers which should be returned

Returns:

the next N available sequence numbers

storeNew

public static org.eclipse.jgit.transport.ReceiveCommand storeNew(org.eclipse.jgit.lib.ObjectInserter ins,
                                                                 String name,
                                                                 int val)
                                                          throws IOException

Throws:

IOException