org.dizitart.no2.sync

Interface SyncTemplate

All Known Implementing Classes:

DataGateSyncTemplate

public interface SyncTemplate

An interface for the DataGate sync operations.

Since:

1.0

Method Summary

Modifier and Type	Method and Description
boolean	change(ChangeFeed changeFeed) Uploads the local changes to the server.
ChangeFeed	changedSince(FeedOptions feedOptions) Downloads the list of changes from the server.
void	clear() Clears the remote collection.
java.util.List<Document>	fetch(int offset, int limit) Fetches all documents from remote.
java.lang.String	getCollectionName() Gets the name of the remote collection.
boolean	isOnline() Checks if the server is online and reachable.
void	releaseLock(java.lang.String issuer) Releases the synchronization lock on the remote collection.
long	size() Gets the size of the remote collection.
boolean	trySyncLock(TimeSpan expiryDelay, java.lang.String issuer) Tries to acquire a synchronization lock on the remote collection.

Method Detail

changedSince

ChangeFeed changedSince(FeedOptions feedOptions)

Downloads the list of changes from the server.

Parameters:

feedOptions - options to fetch the change feed

Returns:

the list of changes

change

boolean change(ChangeFeed changeFeed)

Uploads the local changes to the server.

Parameters:

changeFeed - the list of changes to upload

Returns:

true if the operation is successful; false otherwise.

fetch

java.util.List<Document> fetch(int offset,
                               int limit)

Fetches all documents from remote.

Parameters:

offset - pagination offset

limit - pagination limit

Returns:

list of documents from remote.

size

long size()

Gets the size of the remote collection.

Returns:

the size in long

clear

void clear()

Clears the remote collection.

isOnline

boolean isOnline()

Checks if the server is online and reachable.

Returns:

true if online; false otherwise.

getCollectionName

java.lang.String getCollectionName()

Gets the name of the remote collection.

Returns:

the name of the remote collection.

trySyncLock

boolean trySyncLock(TimeSpan expiryDelay,
                    java.lang.String issuer)

Tries to acquire a synchronization lock on the remote collection. Before start of replication, a sync lock must be acquired on remote collection. If the acquisition is unsuccessful, replication will not occur and it will be retried in next iteration.

If the expiryDelay is expired, then a new lock will be acquired overwriting previous lock information.

Lock information should be maintain as a metadata in the remote database in a separate collection/table than the remote collection.

Parameters:

expiryDelay - the expiry delay

issuer - originator of the change feed

Returns:

the boolean

releaseLock

void releaseLock(java.lang.String issuer)

Releases the synchronization lock on the remote collection.