Open Source Replication and Synchronization Tools Written in Java

• SymmetricDS - SymmetricDS is a web based, database independent, data synchronization system. Beyond replicating tables between relational databases the software incorporates functionality to handle a large number of databases, manage low-bandwidth connections and work within periods of network outage. The system supports two way replication, guaranteed delivery and multiple active schemas.
• Daffodil Replicator - Daffodil Replicator performs data replication based on the 'Publish and Subscribe' model. Replicator supports bi-directional data replication by either capturing a data source snapshot or synchronizing the changes. It monitors data changes, synchronizes all data changes on periodic basis or on-demand. Replicator can use pre-defined conflict resolution algorithms to resolve conflicts between data sources.
• drS - The db4o Replication System (dRS) is a replication system that leverages Hibernate. It enables synchronization of objects bi-directionally between distributed instances of relational databases such as Oracle or MySQL.
• Pollux - Pollux provides a framework for synchronizing data sources which share the same data format. The Record inferface of Pollux provides an abstractions for most kinds of data records, these may include PIM, database records or file/directories.
• Bhavaya - Bhavaya is library that supports real-time synchronized up-to-date access to continually changing data. The Bhavaya persistence layer is different from other implementations such as Hibernate and Castor in that the properties of Bhavaya's objects always reflect the current value of the data in the database.
• GCalDaemon - GCALDaemon offers two-way synchronization between Google Calendar and various iCalendar compatible calendar applications. GCALDaemon is primarily designed as a calendar synchronizer but it can also be used as a Gmail notifier, Address Book importer, Gmail terminal and RSS feed converter.
• Funambol Mobile Application server - The Funambol Mobile Application server ( originally named Sync4j )includes a certified implementation of the Open Mobile Alliance (OMA) Data Synchronization and Device Management protocols (OMA DS and DM, formerly known as SyncML).