Transactions Providing XA Transactions

XA describes the interface between the global transaction manager and the local resource manager. XA allows multiple resources (such as databases, application servers, message queues, transactional caches, etc.) to be accessed within the same transaction, thereby preserving the ACID properties across applications. XA uses a two-phase commit to ensure that all resources either commit or rollback any particular transaction consistently (all do the same).

When you implement the XAResource interface, Hazelcast provides XA transactions. You can obtain the HazelcastXAResource instance via the HazelcastInstance getXAResource method. You can see the HazelcastXAResource source code here.

Below is example code that uses Atomikos for transaction management.

UserTransactionManager tm = new UserTransactionManager();
tm.setTransactionTimeout(60);
tm.begin();

HazelcastInstance hazelcastInstance = Hazelcast.newHazelcastInstance();
HazelcastXAResource xaResource = hazelcastInstance.getXAResource();

Transaction transaction = tm.getTransaction();
transaction.enlistResource(xaResource);
// other resources (database, app server etc...) can be enlisted

try {
  TransactionContext context = xaResource.getTransactionContext();
  TransactionalMap map = context.getMap("m");
  map.put("key", "value");
  // other resource operations
  
  transaction.delistResource(xaResource, XAResource.TMSUCCESS);
  tm.commit();
} catch (Exception e) {
  tm.rollback();
}