package org.infinispan.lucene.impl;
import java.io.IOException;
import javax.transaction.TransactionManager;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.LockFactory;
import org.infinispan.Cache;
import org.infinispan.commons.CacheException;
import org.infinispan.lifecycle.ComponentStatus;
/**
* <p>Factory for locks obtained in <code>InfinispanDirectory</code>, this factory produces instances of
* <code>TransactionalSharedLuceneLock</code>.</p> <p>Usually Lucene acquires the lock when creating an IndexWriter and
* releases it when closing it; these open-close operations are mapped to transactions as begin-commit, so all changes
* are going to be effective at IndexWriter close. The advantage is that a transaction rollback will be able to undo all
* changes applied to the index, but this requires enough memory to hold all the changes until the commit.</p> <p>Using
* a TransactionalSharedLuceneLock is not compatible with Lucene's default MergeScheduler: use an in-thread
* implementation like SerialMergeScheduler <code>indexWriter.setMergeScheduler( new SerialMergeScheduler()
* );</code></p>
*
* @author Sanne Grinovero
* @author Lukasz Moren
* @see TransactionalSharedLuceneLock
* @see org.apache.lucene.index.SerialMergeScheduler
* @since 4.0
*/
public class TransactionalLockFactory extends LockFactory {
public static final TransactionalLockFactory INSTANCE = new TransactionalLockFactory();
/**
* {@inheritDoc}
*/
@Override
public TransactionalSharedLuceneLock obtainLock(Directory dir, String lockName) throws IOException {
if (!(dir instanceof DirectoryLucene)) {
throw new UnsupportedOperationException("TransactionalSharedLuceneLock can only be used with DirectoryLucene, got: " + dir);
}
DirectoryLucene infinispanDirectory = (DirectoryLucene) dir;
Cache cache = infinispanDirectory.getDistLockCache();
String indexName = infinispanDirectory.getIndexName();
TransactionManager tm = cache.getAdvancedCache().getTransactionManager();
if (tm == null) {
ComponentStatus status = cache.getAdvancedCache().getComponentRegistry().getStatus();
if (status.equals(ComponentStatus.RUNNING)) {
throw new CacheException(
"Failed looking up TransactionManager. Check if any transaction manager is associated with Infinispan cache: \'"
+ cache.getName() + "\'");
} else {
throw new CacheException("Failed looking up TransactionManager: the cache is not running");
}
}
TransactionalSharedLuceneLock lock = new TransactionalSharedLuceneLock(cache, indexName, lockName, tm);
CommonLockObtainUtils.attemptObtain(lock);
return lock;
}
}